PSTV US Equity☆

10-K

Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended

December 31, 2025

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number 001-34375

PLUS THERAPEUTICS, INC.

(Exact name of Registrant as Specified in Its Charter)

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (737) 255-7194

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Common Stock, par value $0.001 per share PSTV Nasdaq Capital Market

Securities registered pursuant to Section 12(g) of the Act:

None.

Indicate by check mark if the registrant is a well-known seasoned issuer as defined in Rule 405 of the Securities Act. Yes ☐No☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes ☐No☒

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer ☐ Accelerated Filer ☐

Non-Accelerated Filer ☒ Smaller reporting company ☒

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the common stock of the registrant held by non-affiliates of the registrant on June 30, 2025, the last business day of the registrant’s most recently completed second fiscal quarter, was $31.9 million based on the closing sales price of the registrant’s common stock on June 30, 2025 as reported on the Nasdaq Capital Market, of $0.35 per share.

As of March 10, 2026, there were 171,550,698 shares of the registrant’s common stock issued and outstanding.

DOCUMENTS INCORPORATED BY REFERENCE:

Portions of the registrant’s definitive proxy statement for its 2026 Annual Meeting of Stockholders, which will be filed with the United States Securities and Exchange Commission within 120 days of December 31, 2025, are incorporated by reference into Part III of this Annual Report on Form 10-K.

Table of Contents

PLUS THERAPEUTICS, INC.

ANNUAL REPORT ON FORM 10-K FOR THE YEAR ENDED DECEMBER 31, 2025

TABLE OF CONTENTS

Page

PART I

Item 1. Business 5

Item 1A. Risk Factors 26

Item 1B. Unresolved Staff Comments 53

Item IC. Cybersecurity 53

Item 2. Properties 54

Item 3. Legal Proceedings 54

Item 4. Mine Safety Disclosures 54

PART II

Item 6. [Reserved] 55

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 69

Item 8. Financial Statements and Supplementary Data 70

Item 9A. Controls and Procedures 104

Item 9B. Other Information 104

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspection 105

PART III

Item 10. Directors, Executive Officers and Corporate Governance 105

Item 11. Executive Compensation 105

Table of Contents

Item 14. Principal Accounting Fees and Services 105

PART IV

Item 15. Exhibits, Financial Statement Schedules 106

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This report contains certain statements that may be deemed “forward-looking statements” within the meaning of U.S. securities laws, including statements regarding clinical trials, expected operations and upcoming developments. All statements, other than statements of historical fact, that address activities, events or developments that we intend, expect, project, believe or anticipate and similar expressions or future conditional verbs such as will, should, would, could or may occur in the future are forward-looking statements. Such statements are based upon certain assumptions and assessments made by our management in light of their experience and their perception of historical trends, current conditions, expected future developments and other factors they believe to be appropriate.

These statements include, without limitation, statements about our anticipated expenditures, including research and development, and general and administrative expenses; our intent or ability to regain and maintain compliance with Nasdaq listing standards; our strategic collaborations and license agreements, intellectual property, U.S. Food and Drug Administration and European Medicines Agency approvals and interactions and government regulation; the potential size of the market for our product candidates; our research and development efforts; results from our preclinical and clinical studies and the implications of such results regarding the efficacy or safety of our product candidates; the safety profile, pathways, and efficacy of our product candidates and formulations; anticipated advantages of our product candidates over other products available in the market and being developed; the populations that will most benefit from our product candidates and indications that will be pursued with each product candidate; anticipated progress in our current and future clinical trials; plans and strategies to create novel technologies; our IP strategy; competition; future development and/or expansion of our product candidates and therapies in our markets; sources of competition for any of our product candidates; our pipeline; our ability to generate product or development revenue and the sources of such revenue; our ability to effectively manage our gross profit margins; our ability to obtain and maintain regulatory approvals; expectations as to our future performance; our ability to satisfy our obligations under the terms of our capital raising transactions including registering shares issuable in such transactions; portions of the “Liquidity and Capital Resources” section of this Annual Report on Form 10-K (“Form 10-K”) including our potential need for additional financing and the availability thereof; our ability to integrate into our business and operations, develop, fully utilize and monetize acquired assets; our ability to continue as a going concern; our ability to repay or refinance some or all of our outstanding indebtedness and our ability to raise capital in the future; our ability to transfer the drug and medical device product manufacturing to a contract drug and medical device manufacturing organization; the potential enhancement of our cash position through development, marketing, and licensing arrangements; our ability to timely and efficiently launch our CNSide® Cerebrospinal Fluid Tumor Cell Enumeration test (the “CNSide Test”), and expand the CNSide platform for Immunocytochemistry (“ICC”), Fluorescence In Situ Hybridization (“FISH”) and Next Generation Sequencing (“NGS”); receipt of grant revenue; and a material security breach or cyber security attack affecting our operations and property. The forward-looking statements included in this report could differ materially from those expressed or implied by these forward-looking statements because of risks, uncertainties and other factors that include, but are not limited to, the risks described under Risk Factors” included below.

We encourage you to read the risks described under “Risk Factors” and elsewhere in this report carefully. We caution you not to place undue reliance on the forward-looking statements contained in this report. These statements, like all statements in this report, speak only as of the date of this report (unless an earlier date is indicated) and we undertake no obligation to update or revise any forward-looking statements to reflect events, trends or circumstances after the date they are made unless we have an obligation under U.S. federal securities laws to do so. Such forward-looking statements are not guarantees of future performance.

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PART I

Item 1. Business

References to “Plus Therapeutics,” the “Company,” “we,” “us” and “our” refer to Plus Therapeutics, Inc. References to “Notes” refer to the Notes to Financial Statements included herein (refer to Item 8).

General

Plus Therapeutics is a U.S. healthcare company developing and commercializing precision diagnostics and targeted radiopharmaceuticals for central nervous system (“CNS”) cancers. CNSide Diagnostics, LLC (“CNSide Diagnostics”) is our wholly owned subsidiary that develops and commercializes proprietary laboratory-developed tests, such as CNSide®, designed to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas. In radiopharmaceuticals, our lead candidate, rhenium (186Re) obisbemeda, is designed specifically for CNS cancers including recurrent glioblastoma (“GBM”), leptomeningeal metastases (“LM”), and pediatric brain cancers (“PBC”) by direct localized delivery utilizing approved standard-of-care tissue access such as with convection-enhanced delivery (“CED”) and intraventricular brain (Ommaya reservoir) catheters. Our acquired radiotherapeutic candidate, Rhenium-188 NanoLiposome Biodegradable Alginate Microsphere (“188RNL-BAM”) is designed to treat many solid organ cancers including primary and secondary liver cancers by intra-arterial injection.

Traditional approaches to radiation therapy for cancer, such as external beam radiation, have many disadvantages including continuous treatment for four to six weeks (which is onerous for patients), that the radiation damages healthy cells and tissue, and that the amount of radiation delivered is very limited and, therefore, is frequently inadequate to fully destroy the cancer.

Our novel radioactive drug formulations, medical devices and therapeutic candidates have the potential to overcome these disadvantages as they are designed to deliver safe and effective doses of radiation at the tumors—potentially in a single treatment. To achieve this, we have developed innovative approaches to drug formulation, including encapsulating radionuclides such as rhenium isotopes with nanoliposomes and microspheres. Our formulations are intended to achieve elevated patient-absorbed radiation doses and extend retention times such that the clearance of the isotope occurs after significant and essentially complete radiation decay, which will contribute and provide less normal tissue/organ exposure and improved safety margins.

By minimizing radiation exposure to healthy tissues while simultaneously maximizing locoregional delivery and, thereby, efficacy, we hope to reduce the radiation toxicity for patients, improving their quality of life and life expectancy. Our radiotherapeutic platform, combined with advances in neurosurgery, nuclear medicine, interventional radiology, neuro-oncology, and radiation oncology, affords us the opportunity to target a broad variety of cancer types.

The CNSide Cerebrospinal Fluid Assay is currently being utilized in the ReSPECT-LM clinical trial funded by the Cancer Prevention and Research Institute of Texas (“CPRIT”). In connection with our business plan for developing the CNSide Platform, we formed CNSide Diagnostics and our board of directors appointed a board of managers for CNSide Diagnostics. We re-introduced the CNSide Cerebrospinal Fluid Tumor Cell Enumeration test (the “CNSide Test”), which is a laboratory developed test (“LDT”) in August 2025. The laboratory for the CNSide Test in Houston, Texas has received a certificate of accreditation from the Centers for Medicare & Medicaid Services (“CMS”) which deems the lab compliant with Clinical Laboratory Improvement Amendments (“CLIA”) regulations. Furthermore, CNSide Diagnostics has signed national agreements to provide the CNSide Test with UnitedHealthcare Insurance Company and Humana, Inc. effective September 15 and October 29, 2025, respectively. These agreements expand access to more than 67 million covered lives across the United States.

Our headquarters is located in Houston, Texas, in proximity to world-class cancer institutions and researchers.

Pipeline

Our most advanced investigational drug, rhenium (186Re) obisbemeda, is a patented radiotherapy potentially useful for patients with CNS and other cancers. Preclinical study data describing the use of rhenium (186Re) obisbemeda for several cancer targets have been published in peer-reviewed journals and reported at a variety of medical society peer-reviewed meetings. Besides GBM, LM and PBC, rhenium (186Re) obisbemeda has been reported to have potential applications for head and neck cancer, ovarian cancer, breast cancer and peritoneal metastases.

The rhenium (186Re) obisbemeda technology was part of a licensed radiotherapeutic portfolio that we acquired from NanoTx, Corp. (“NanoTx”) on May 7, 2020. The licensed radiotherapeutic has been evaluated in preclinical studies for several cancer targets and we have an active $3.0 million award from U.S. National Institutes of Health/National Cancer Institute which is expected to provide financial support for the continued clinical development of rhenium (186Re) obisbemeda for recurrent GBM through the completion of a Phase 2 clinical trial, including enrollment of up to 55 patients.

Potential Advantages of Rhenium (186Re) obisbemeda as a treatment for Recurrent GBM

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Rhenium (186Re) obisbemeda is a novel injectable radiotherapy designed to deliver targeted, high dose radiation directly into GBM tumors in a safe, effective, and convenient manner that may ultimately prolong patient survival. rhenium (186Re) obisbemeda is composed of the radionuclide Rhenium-186 and a nanoliposomal carrier, and is infused in a highly targeted, controlled fashion, directly into the tumor via precision brain mapping and CED catheters. Potential benefits of rhenium (186Re) obisbemeda compared to standard external beam radiotherapy or external beam radiation therapy (“EBRT”) include:

•

The rhenium (186Re) obisbemeda radiation dose delivered to patients may be up to 20 times greater than what is possible with commonly used EBRT, which, unlike EBRT and proton beam devices, spares normal tissue and the brain from radiation exposure.

•

Rhenium (186Re) obisbemeda can be visualized in real-time during administration, possibly giving clinicians better control of radiation dosing, distribution and retention.

•

Rhenium (186Re) obisbemeda is designed to effectively treat a bulk tumor and microscopic disease that has already invaded healthy tissue.

•

Rhenium (186Re) obisbemeda is infused directly into the targeted tumor by CED catheter insertion using MRI guided software to avoid critical patient neurological structures and neural pathways and also bypasses the blood brain barrier, which delivers the therapeutic product where it is needed. Importantly, it reduces radiation exposure to healthy cells, in contrast to EBRT, which passes through normal tissue to reach the tumor, continuing its path through the tumor, hence being less targeted and selective.

•

Rhenium (186Re) obisbemeda is given during a single, short, in-patient hospital visit, and is available in all hospitals with nuclear medicine and neurosurgery, while EBRT requires out-patient visits five days a week for approximately four to six weeks.

ReSPECT-GBM Trial for Recurrent GBM

GBM affects approximately 15,000 patients annually in the U.S. and is the most common and lethal form of brain cancer. The average life expectancy with GBM is less than 24 months, with a one-year survival rate of 40% and a five-year survival rate of around 5%. There is no clear standard of care for recurrent GBM and the few currently approved treatments provide only marginal survival benefit and are associated with significant side effects, which limit dosing and prolonged use. Approximately 90% of patients experience GBM tumor recurrence at or near the original tumor location, yet there are no FDA-approved treatments in the recurrent or progressive setting that can significantly extend a patient’s life. GBM routinely presents with headaches, seizures, vision changes and other significant neurological complications, with a significant compromise in quality of life. Despite the best available medical treatments, the disease remains incurable. Even after efforts to manage the presenting signs and symptoms and completely resect the initial brain tumor, some microscopic disease almost always remains, and tumor regrowth occurs within months. Complete surgical removal of GBM is usually not possible and GBM is often resistant or quickly develops resistance to most available current and investigational therapies. Today, the treatment of GBM remains a significant challenge and it has been nearly a decade since the FDA approved a new therapy for this disease, and these more recent approvals have not improved the overall survival (“OS”) for GBM patients over past decades, and a significant unmet medical need persists.

While EBRT has been shown to be safe and has temporary efficacy in many malignancies including GBM, typically at absorbed, fractionated radiation dose of ~30 Gray in GBM, this maximum possible administered dose is always limited by toxicity to the normal tissues surrounding the malignancy and because EBRT requires fractionation to manage toxicity, maximum EBRT limits are typically reached before long-term efficacy is reached. Because of this limitation, EBRT cannot provide a cure or long-term control of GBM and GBM always recurs within months after EBRT. In contrast, locally delivered and targeted radiopharmaceuticals that precisely deliver radiation in the form of beta particles, such as Iodine-131 for thyroid cancer, are known to be safe and effective and minimize exposure to normal cells and tissues especially with optimal administered dose and minimizing exposure to normal tissue. The locally delivered rhenium (186Re) obisbemeda is designed for and provides patient tolerability and safety. Though no rhenium (186Re) obisbemeda head-to-head trial with chemo, immune, EBRT or systemic radiopharmaceutical products have been conducted, patient tolerability and safety considerations have been reported as expected.

In 2020, the FDA granted rhenium (186Re) obisbemeda orphan drug designation for the treatment of GBM and Fast Track designation for the treatment of recurrent GBM.

Rhenium (186Re) obisbemeda is under clinical investigation in a Phase 1/2 multicenter, sequential cohort, open-label, volume and dose escalation study (“ReSPECT-GBM”) of the safety, tolerability, and distribution of rhenium (186Re) obisbemeda given by CED catheters to patients with recurrent or progressive malignant glioma after standard surgical, radiation, and/or chemotherapy treatment. The trial is funded through Phase 2 in large part by a National Institute of Health/National Cancer Institute grant.

We completed Phase 1 of our ReSPECT-GBM Trial and are targeting full enrollment into Phase 2 by the end of 2026.

ReSPECT-LM Clinical Trials for LM

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LM is a rare complication of cancer in which the disease spreads to the membranes (meninges) surrounding the brain and spinal cord. The incidence of LM is growing and occurs in approximately 5%, or more, of people with late-stage cancer, or 110,000 people in the U.S. each year. It is highly lethal with an average one-year survival of just 7%. All solid cancers, particularly breast, lung, GI, and melanoma, have the potential to spread to the leptomeninges.

The ReSPECT-LM Phase 1 clinical trial (ClinicalTrials.gov NCT05034497) was preceded by preclinical studies in which tolerance to doses of rhenium (186Re) obisbemeda as high as 1,075 Gy were shown in animal models with LM without significant observed toxicity. Furthermore, treatment led to a marked reduction in tumor burden in both C6 and MDA-231 LM models.

Upon receiving acceptance of our Investigational New Drug application and Fast Track designation by the FDA for rhenium (186Re) obisbemeda for the treatment of LM in November 2021, we initiated the trial and began screening patients for the ReSPECT-LM Phase 1 clinical trial in the fourth quarter of 2021.

ReSPECT-LM is a multi-center, sequential cohort, open-label, dose escalation study evaluating the safety, tolerability, and efficacy of a single-dose application of rhenium (186Re) obisbemeda administered through intrathecal infusion to the ventricle of patients with LM after standard surgical, radiation, and/or chemotherapy treatment. The primary endpoint of the study is the incidence and severity of adverse events and dose limiting toxicities, together with determining the maximum tolerated and recommended Phase 2 dose. Full enrollment in the Phase 1 trial was achieved at the end of 2024, and we announced the trial completion on February 26, 2025. Trial closeout procedures are now taking place including final data review and monitoring, and a clinical study report and manuscript will be prepared.

On September 19, 2022, we entered into a Cancer Research Grant Contract (the “CPRIT Contract”), effective as of August 31, 2022, with CPRIT, pursuant to which CPRIT provides us a grant of up to $17.6 million (the “CPRIT Grant”) over a three-year period to fund the continued development of rhenium (186Re) obisbemeda for the treatment of patients with LM through Phase 2 of the ReSPECT LM clinical trial. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar from us for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of rhenium (186Re) obisbemeda based on specific dollar thresholds until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements. As of December 31, 2025, we had received approximately $15.9 million in milestone payments under the CPRIT Contract.

Interim results showed that a single treatment with rhenium (186Re) obisbemeda resulted in a consistent decreased cerebrospinal fluid (“CSF”) circulating tumor cell (“CTC”) count/ml and was tolerated by all LM patients. Rhenium (186Re) obisbemeda is an outpatient administration and treatment and is easily and safely administered through a standard intraventricular catheter (Ommaya Reservoir), distributed promptly throughout the CSF, and with durable retention in the leptomeninges at least through day seven. All patients have shown well tolerated prompt and durable rhenium (186Re) obisbemeda distribution throughout the subarachnoid space.

In November 2023, the FDA granted orphan drug designation to rhenium (186Re) obisbemeda for the treatment of patients with breast cancer with LM.

On December 12, 2023, we announced our partnership with K2bio to implement the CNSide Test.

On February 26, 2025, we announced the completion of the ReSPECT-LM Phase 1 single-dose escalation trial, having determined a recommended Phase 2 dose. Enrollment in Cohort 6 was completed (75.0 mCi). The Cohort 4 dose (44.1 mCi) was determined to be the recommended Phase 2 dose with no dose-limiting toxicities observed at that dose level. One patient at the Cohort 4 dose was observed to have achieved a complete response, as evidenced by the eradication of tumor cells in the cerebrospinal fluid—a key therapeutic endpoint.

In March 2025, the FDA granted orphan drug designation to rhenium (186Re) obisbemeda for the treatment of LM in patients with lung cancer.

In November 2025, we had our end of phase 1 meeting with the FDA. During this meeting, FDA conveyed that while accelerated approval may be appropriate for this indication, there are insufficient data to support the use of CTCs as an intermediate clinical endpoint, and there was discussion that additional steps would be necessary to validate CTCs as a surrogate endpoint to potentially support other future applications. The FDA recommended that the study evaluate an endpoint with established clinical benefit, such as overall survival, while encouraging further study of reported outcomes and neurologic function as endpoints that could potentially support a marketing application. We agreed with FDA that CTCs could be considered for use as a secondary endpoint. We discussed with the FDA a randomized controlled trial design approach and that the study may include an itrathecal chemotherapeutic as a comparator, as well as approaches to standardize the comparator and any additional interventions available under the trial protocol. The FDA conveyed it may be reasonable to incorporate multiple histologies (i.e., multiple underlying disease etiologies) in a single trial. We plan to consider the Agency’s feedback and propose an updated protocol for our next study for FDA’s feedback.

In December 2025, we reported completion of the ReSPECT-LM single dose trial showed rhenium (186Re) obisbemeda was well-tolerated up to a maximum tolerated dose of 66mCi, with a recommended phase 2 dose of 44.1 mCi, and absorbed doses delivered of >300 Gy observed. We also reported the ReSPECT-LM open label, multidose Phase 1/2 trial initiation to identify maximum tolerated dose across varying dosing intervals and to characterize efficacy of multiple doses at optimal dose selected by assessing response using the CNSide Test. Enrollment in Cohort 1 has begun with delivery of 13.2 mCi at 3 intervals with one patient receiving all doses without dose limiting toxicity.

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Our ReSPECT LM Multi-dose Phase 1/2 Study is currently enrolling patients for the Phase 2 portion of the Study.

ReSPECT-PBC Clinical Trial for Pediatric Brain Cancer

The average annual age adjusted mortality rate for children aged 0-14 for malignant brain (and other CNS) tumors is 0.71/100,000, making it the most common cause of death and cancer death in this age group. The 2021 World Health Organization Classification of CNS Tumors classifies gliomas, glioneuronal tumors, and neuronal tumors into six different families: (1) adult-type diffuse gliomas; (2) pediatric-type diffuse low-grade gliomas; (3) pediatric-type diffuse high-grade gliomas (“HGG”); (4) circumscribed astrocytic gliomas; (5) glioneuronal and neuronal tumors; and (6) ependymomas.

In August 2021, we announced plans for treating pediatric brain cancer at the 2021 American Association of Neurological Surgeons Annual Scientific Meeting. In July 2021, we reported that we had received FDA feedback pertaining to a pre-IND meeting briefing package in which the FDA stated that we are not required to perform any additional preclinical or toxicology studies. A new IND submission was made in 2023.

Pediatric high-grade gliomas can be found almost anywhere within the CNS; however, they are most commonly found within the supratentorium. The highest incidence of supratentorial, high-grade gliomas in pediatrics appears to occur in children aged 15 to 19 years, with a median age of approximately nine years. Overall, pediatric high-grade glioma confers a three-year progression free survival (“PFS”) of 11 ± 3% and three-year OS of 22 ±5%. One-year PFS is as low as 40% in recent trials. Ependymomas are slow-growing central nervous system tumors that involve the ventricular system. Diagnosis is based on MRI and biopsy and survival rate depends on tumor grade and how much of the tumor can be removed. Grade II pathology was associated with significantly improved OS compared to Grade III (anaplastic) pathology (five-year OS = 71 ± 5% vs. 57 ± 10%; p = 0.026). Gross total resection compared to subtotal resection was associated with significantly improved OS (five-year OS = 75 ± 5% vs. 54 ± 8%; p = 0.002).

Overall, pediatric HGG and ependymoma are extremely difficult-to-treat pediatric brain tumors, frequently aggressive, and in recurrent settings, carry an extremely poor prognosis.

Effective September 1, 2024, we entered into an agreement with the Department of Defense office of the Congressionally Directed Medical Research Programs to receive a $3.0 million fund for research and development purposes (“DoD Award”) over a three-year period. The DoD Award will be used to support the planned expansion of our clinical trial for pediatric brain cancer. We anticipate enrolling our first patient for our Phase 1 ReSPECT-PBC clinical trial in 2026.

On June 25, 2025, we announced that the FDA cleared our IND application (No. 168178) for rhenium (186Re) obisbemeda for the treatment of pediatric patients with supratentorial recurrent, refractory, or progressive high-grade glioma (“HGG”) and ependymoma. The Phase 1/2a trial is a two-part, single-arm, prospective study aimed at determining the maximum tolerated dose (“MTD”), safety, and tolerability of rhenium (186Re) obisbemeda in pediatric patients aged 6 to 21 years (with consideration for patients up to 25 years on a case-by-case basis).

Key elements of the trial design include:

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Phase 1a/b (dose escalation): This phase will enroll an estimated 24 patients using a modified 3+3 dose escalation scheme to establish the MTD and recommended Phase 2 dose (“RP2D”). Safety assessment and alignment with the FDA will occur at defined intervals.

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Phase 2a: This phase will enroll approximately 32 patients (12 with ependymoma and 20 with HGG) at the RP2D to assess efficacy.

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We anticipate beginning enrollment in our ReSPECT-PBC clinical trial, with our first patient enrolled, in 2026.

Rhenium-188 NanoLiposome Biodegradable Alginate Microsphere Technology

In January 2022, we announced that we licensed Biodegradable Alginate Microsphere (“BAM”) patents and technology from The University of Texas Health Science Center at San Antonio (“UTHSCSA”) to expand our tumor targeting capabilities and precision radiotherapeutics pipeline. We intend to combine our Rhenium NanoLiposome technology with the BAM technology to create a novel radioembolization technology. Initially, we intend to utilize the Rhenium-188 isotope, 188RNL-BAM for the intra-arterial embolization and local delivery of a high dose of targeted radiation for a variety of solid organ cancers such as hepatocellular cancer, hepatic metastases, pancreatic cancer and many others.

Preclinical data from an ex vivo embolization experiment in which Technetium99m-BAM was intra-arterially delivered to a bovine kidney perfusion model was presented at the Society of Interventional Radiology Annual Scientific Meeting. The study concluded that the technology required for radiolabeling BAM could successfully deliver, embolize and retain radiation in the target organ. 188RNL-BAM is a preclinical investigational device we intend to further develop and move into clinical trials. Specifically, in 2022 we transferred the 188RNL-BAM technology from UTHSCSA, and began planning to develop the product and complete early preclinical studies to support a future

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FDA IND submission. Our intended initial clinical target is liver cancer which is the sixth most common and third deadliest cancer worldwide. It is a rare disease with increasing U.S. annual incidence (42,000) and deaths (30,000).

Subsequently, the FDA has informed us that 188RNL-BAM will be regulated as a medical device under the Federal Food, Drug, and Cometic Act (“FDCA”).

The CNSide CSF Assay Platform

The CNSide CSF Assay Platform consists of four LDTs used for detection, quantification, and characterization of tumor cells in patients with LM. The CNSide Platform facilitates tumor cell detection/enumeration and biomarker identification using cellular assays (tumor cell enumeration (“TCE”), immunocytochemistry (“ICC”), and fluorescence in situ hybridization (“FISH”)) and molecular assays (next-generation sequencing (“NGS”)). The CNSide Test is currently being used in the ReSPECT-LM trial as an exploratory endpoint.

Since acquiring the CNSide Platform in 2024, we have established infrastructure to support a scalable and centralized testing laboratory in Houston, TX that will service the U.S. market. We have been executing on our commercial market access strategy, which includes prioritized state licensure, proprietary reimbursement codes, commercial and government payor coverage, and value-based pricing to optimize revenue. We re-introduced the CNSide Platform first in Texas in August of 2025, signed a national agreement to provide the CNSide Test with UnitedHealthcare Insurance Company and Humana, Inc., and obtained state licensure for 49 of 50 US states by January 2026, with the remaining license for the state of New York on track for 2027. In parallel, we expect to launch a portfolio of additional CSF tumor characterization tests that expand our CNSide testing platform later in 2026.

When the CNSide CSF Assay Platform was previously commercially available, market acceptance and adoption were widespread, with several national and regional commercial payor agreements in place and the test in regular use at major cancer centers across the U.S. We are now in contact with the legacy payors and healthcare providers to support our commercial scale up in 2026. Finally, we have hired experienced leadership with expertise in the development and commercialization of clinical diagnostic technologies on a large scale.

Licensing

On December 31, 2021, we entered into a Patent and Technology License Agreement (the “UTHSCSA License Agreement”) with UTHSCSA, pursuant to which UTHSCSA granted us an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of BAM containing nanoliposomes loaded with imaging and/or therapeutic payloads. Therapeutic payloads may include radiotherapeutics, chemotherapeutics, or thermotherapeutics.

The BAM technology is delivered directly into the intra-arterial vascular system via commonly utilized and standard interventional vascular catheters and techniques that allow precise placement into the arterial blood vessels feeding tumors. Once injected, the BAM technology provides a potential dual therapeutic delivery—blocking blood flow to the tumors by alginate microsphere tumor capillary embolization with simultaneous delivery of very high doses of cytotoxic compounds including radiation, such as nanoliposome encapsulated bi-functionally chelated Re-188, for an extended time. Weeks later, the delivered BAM are physiologically metabolized allowing excretion from the body. Rhenium-188 is an attractive and ideal therapeutic isotope for this application because of its 16.9 hour half-life, 2.12MEV β-decay and ~3.8mm tissue path-length, and simultaneous 155Kev γ-decay that allow simultaneous SPECT/CT imaging with commonly available imaging equipment to easily and non-invasively monitor product administration, delivery and dosimetry absorbed dose evaluation.

We currently anticipate that we will initially focus on developing 188RNL-BAM as a next-generation radioembolization therapy for liver cancer, in which BAM blocks the hepatic artery segments that supply blood to the malignant tumor while also providing 188RNL radiotherapy directly to the tumor and surrounding tissue. According to the American Cancer Society, liver cancer is a rare disease with an increasing annual incidence and five-year overall survival of only 20%.

The financial terms of the UTHSCSA License Agreement are primarily success-based with milestone and royalty payments contingent on achieving key clinical, regulatory and sales milestones.

The initial inventions and work behind the licensed patents and technologies were developed and led by William Phillips MD, Professor of Nuclear Medicine, and his team at UTHSCSA. The 188RNL-BAM technology incorporates Rhenium-188, or 188Re, a unique isotope for radiotherapeutic embolization owing to its emission of a high energy (2.12Mev) electron (beta particle, 16.9-hour half-life with a 3.8mm decay path length). 188Re also emits 155kev gamma energy that permits high quality, real-time imaging of the BAM construct delivery localization and confirmation. BAMs are not permanent and are anticipated to degrade over time, allowing restoration of blood flow, decreasing radiation resistance, and allowing for safer physiological clearance of 188Re through the kidneys, which may minimize bone marrow toxicity.

The transaction terms include an upfront payment in cash. We are also required to pay development and sales milestone payments, if achieved, and a tiered single-digit royalty on U.S. and European sales. In addition, we may be obligated to pay an annual maintenance fee beginning in 2024.

On March 29, 2020, we entered into a Patent and Know-How License Agreement (the “NanoTx License Agreement”) with NanoTx, pursuant to which NanoTx granted us an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense andto make,

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develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of radiolabeled nanoliposomes.

The transaction terms included an upfront payment of $0.4 million in cash and $0.3 million in our voting stock. The transaction terms also included success-based milestone and royalty payments contingent on key clinical, regulatory and sales milestones, as well as the requirement to pay 15% of any non-dilutive monetary awards or grants received from external agencies to support product development of the nanoliposome encapsulated BMEDA-chelated radioisotope, which includes grants from CPRIT.

The licensed NanoTx portfolio benefits from proprietary nanoliposome-encapsulated technology to encapsulate radionuclides allowing direct local delivery for several cancer targets.

The licensed radiolabeled nanoliposome platform was developed by a multi-institutional consortium based in Texas at the Mays Cancer Center / UTHSCSA MD Anderson Cancer Center led by Dr. Andrew Brenner, MD, PhD, who is the Kolitz Chair in Neuro-Oncology Research and Co-Leader of the Experimental and Developmental Therapeutics Program. The technology was previously owned by NanoTx and funded by both the NIH/NCI and CPRIT. There is an active $3 million award from NIH/NCI that is expected to financially support the continued clinical development of rhenium (186Re) obisbemeda for recurrent GBM.

Manufacturing

For rhenium (186Re) obisbemeda, we have entered into master services agreements with third parties, including Piramal Pharma Solutions, Inc., ABX Advanced Biochemical Compounds GmbH, Telix IsoTherapeutics Group, LLC, Radiomedix, Inc., Alamo Nuclear Pharmacy Services, Inc., and Nuke Med, Inc. (aka SpectronRx) in connection with the development, manufacture, and supply of our rhenium (186Re) obisbemeda drug product. Upon completion of the research and development phase of a drug candidate, certain parts of the manufacturing processes for such candidate may be transferred to contract manufacturers to support clinical trials and commercial release. Upon approval of our drug candidates, we expect our manufacturing capabilities to include validated manufacturing processes for the drug product as well as a quality assurance product release process with the ability to ultimately scale-up the process to meet increasing market demands. We believe our strategic investments in our analytical, development and manufacturing capabilities, including personnel with expertise from drug discovery through drug development, will allow us to advance our product candidates more quickly. Expertise gained in manufacturing our drug products may be applied to other formulations in the future, further leveraging our capabilities.

With respect to CNSide, dedicated manufacturing operations for the CNSide platform have been established, including production of proprietary microfluidic chips and associated reagents. Automation of key production steps, together with defined process and quality controls, has improved efficiency and strengthened manufacturing reliability. These advancements have transitioned CNSide manufacturing from development-stage workflows into a scalable production platform.

The design and planned build-out of the Levit Green facility are advancing, with the objective of increasing production capacity and further standardizing operations. In parallel, ERP infrastructure is being implemented to enhance inventory visibility and production planning in support of anticipated manufacturing growth.

Competition

Our business is conducted in intensely competitive and highly regulated markets. The life science industry is characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary therapeutics. We face competition from a number of sources, some of which may target the same indications as our products, product candidates and laboratory tests, including small and large, domestic and multinational, medical device, biotechnology and pharmaceutical companies, academic institutions, government agencies, private and public research institutions and clinical laboratories. Competitors may have greater experience in, and resources to devote to, developing drugs and clinical laboratory tests, conducting clinical trials, obtaining regulatory clearances or approvals, manufacturing and commercialization.

We expect that product candidates in our pipeline, if approved, would compete on the basis of, among other things, product efficacy and safety; time to market; price, coverage, and reimbursement by third-party payers; extent of adverse side effects; and convenience of treatment procedures.

Competition for our product candidate, particularly rhenium (186Re) obisbemeda and 188RNL-BAM may come from a single or combination therapy in the future.

Currently, there are many other entities pursuing drug development programs for the indications we are currently pursuing with our product candidates.

Significant competitors that have reported drug development programs or clinical laboratory tests at various clinical stages for the various indications listed include, but are not limited to:

Recurrent Glioblastoma

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EnGeneIC, Berg, Istari, AstraZeneca, Novartis, PharmAbcine, Kairos, Midatech, Oncovir, Infuseon, Astellas, NanoPharmaceuticals, Erasca, OX2, Crimson BioPharm, TMUNITY, Pfizer, Arcus, Photolitec, Samus, DNAtrix, ImmVira, BerGenBio, Boston Scientific, BeiGene, GSK, Bristol Myers Squibb, Eli Lilly, Sumitomo, QED, Chimerix, Accenda, Oblato, VBI, INIGHTEC, Sonalasense, VBL, Medicenna, Mimiva, Gilead, CNS Pharmaceuticals, VAXIMM, Incyte, Celularity, Medicinova, Karyopharm, Nerviano Medical Sciences, Merck, Telix, Neonc, Nuvation Bio, Aadi, ERC, Kazia, Xoft, Basilea, Vigo, Biohaven, Bayer, Kintara, CarThera, Everfront Biotech, and others have reported drug development programs at various clinical stages for recurrent GBM.

Leptomeningeal Metastases

Kazia, AstraZeneca, Pfizer, Daiichi-Sankyo, Genentech, Janssen, NRG Oncology, Angiochem, and others have reported drug development programs at various clinical stages for LM.

Pediatric Brain Cancer

AstraZeneca, Bristol Myers Squibb, Chimerix, Celgene, Eli Lilly, Nektar Therapeutics, Istari Oncology, Novartis, NovoCure, Takeda, Y-mAbs, Cellectar, and others have reported drug development programs at various clinical stages for PBC.

Liver Cancer

Boston Scientific, SIR-TEX, ABK Biomedical, and others have reported radioembolization therapy product development programs for liver cancer.

CNSide Test

Menarini, Belay Diagnostics, BillionToOne, FYR Diagnostics, Cerevention, Genomic Testing Cooperative, Predicine, Neogenomics, Quest, and LabCorp are current or potential future competitors of our CNSide Test.

Intellectual Property

Our success depends in large part on our ability to protect our proprietary technology, and to operate without infringing on the proprietary rights of third parties. We rely on a combination of patent, trade secret, copyright and trademark laws, as well as confidentiality agreements, licensing agreements and other agreements, to establish and protect our proprietary rights. Our success also depends, in part, on our ability to avoid infringing patents issued to others.

We license the proprietary formulation and proprietary methods of manufacture of the nanoliposome-encapsulated radionucleotides. rhenium (186Re) obisbemeda, 188RNL-BAM, and their method of manufacture are covered by a U.S. patent that will expire in December 2026. Patent term extension, codified in 35 U.S.C. §156, provides a means of recapturing time lost during the regulatory approval process. Based upon this regulation, we will apply for patent term extension for this patent for the time lost to development and regulatory review for rhenium (186Re) obisbemeda. This has the potential to extend patent coverage for this product for up to another five years.

188RNL-BAM is also covered by a licensed patent family directed to a method of producing liposome-containing alginate microspheres. Any patent granted from applications claiming priority to it is expected to expire in May 2040, not including any patent term adjustment or patent term extension and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees. The patent family includes issued patents in Japan, Singapore, Canada, and Mexico, in addition to pending applications in the United States, Canada, Israel, India, Mexico, Saudi Arabia, Thailand, South Africa, Vietnam, Philippines, China, Europe, Brazil, Singapore, Indonesia, Malaysia, Hong Kong, Australia, and New Zealand.

188RNL-BAM is also covered by a licensed patent family directed to a method for post-manufacture loading of a liposome-containing hydrogel microsphere. Patent granted from applications in this family are expected to expire in March 2042, not including any patent term adjustment or patent term extension and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees. The patent family includes applications pending in the United States, Australia, Canada, Brazil, South Korea, China, Europe, Mexico, and Israel.

We co-own a patent family directed to methods of treating a disease, including, but not limited to cancer, comprising administering 186Re and 188Re nanoliposomes via CED. Any patents issued from applications in this family are expected to expire in November 2041, not including any patent term adjustment or patent term extension and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees. The patent family includes applications pending in the U.S., Australia, Brazil, Canada, China, Europe, Indonesia, Israel, Japan, South Korea, Malaysia, Hong Kong, and Mexico.

We co-own a patent family directed to methods of treating leptomeningeal metastases comprising administering 186Re and/or 188Re nanoliposomes via an intraventricular reservoir. Any patent granted from applications in this family are expected to expire in January 2043, not including any patent term adjustment or patent term extension and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees. The patent family includes applications pending in the U.S., Australia, Brazil, Canada, China, Europe, Indonesia, Israel, Japan, South Korea, Malaysia, and Mexico.

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We own a patent family directed to a method of manufacturing a polymeric matrix encapsulating microsomes. Any patent granted from applications in this family is expected to expire in December 2043, not including any patent term adjustment or patent term extension and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees. Applications are pending in the PCT and U.S. The 30-month deadline to file national stage applications claiming priority to the PCT application is June 2025.

We have broad patent protection related to the CNSide Platform, including our ownership of the following patents, patent families and applications:

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A patent family directed to a microflow device for separating or isolating cells from a bodily fluid or other liquid sample. There are patents in the U.S., China, Europe (validated in France, Germany, Italy, Spain, and the United Kingdom), Hong Kong, China, and Japan. There is an application pending in the U.S. The patents will expire in 2026 assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

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A patent family directed to a microflow device for separating or isolating cells from a bodily fluid or other liquid sample. There are patents in the U.S., Canada, China, and Hong Kong. The patents will expire in 2026 and 2027 assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

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A patent family directed to a device and methods for isolating target biomolecules or cells from samples. There are patents in the U.S., Australia, Europe (validated in the United Kingdom, France, Spain, Germany, Switzerland, and Italy), China, Japan, Canada, and Hong Kong. There is an application pending in the U.S. The patents will expire in 2030 and 2031 assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

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A patent family directed to reagents containing binding moieties conjugated to dextran moieties, methods of making such reagents, and use of such reagents in a variety of molecular and cellular assays. There are patents in the U.S., Japan, China, Canada, Europe (validated in France, Germany, Italy, Switzerland, and the United Kingdom), and Hong Kong. The patents will expire in 2031 assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

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A U.S. patent directed to a microflow apparatus. This patent will expire in May 2030 assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

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A U.S. patent directed to a method of inhibiting cellular aggregation in a biologically active sample. This patent will expire in September 2031 assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

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U.S. and European patent applications directed to a formulation to inactivate pathogens. Any patent issuing from these applications is expected to expire in 2041, not including any patent term adjustment or patent term extension and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees.

Government Regulation and Product Approval

Government authorities in the United States, at the federal, state and local level, and in other countries and jurisdictions, including the European Union (“EU”), extensively regulate, among other things, the research, development, testing, manufacture, quality control, approval, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, post-approval monitoring and reporting, and import and export of pharmaceutical and medical device products. The processes for obtaining regulatory clearances, authorizations, or approvals in the United States and in foreign countries and jurisdictions, along with compliance with applicable statutes and regulations and other regulatory authorities, require the expenditure of substantial time and financial resources.Nanoparticle oncology drug candidates must receive regulatory approvals from the European Commission and the FDA and from other government authorities prior to sale of the product candidates in their respective jurisdictions.

FDA Approval Process

In the United States, pharmaceutical and medical device products are subject to extensive regulation by the FDA. Manufacturers of pharmaceutical and medical device products may also be subject to state and local regulation. The FDCA and other federal and state statutes and regulations govern, among other things, the research, development, testing, manufacture, storage, recordkeeping, approval, labeling, promotion and marketing, distribution, post-approval monitoring and reporting, sampling, and import and export of pharmaceutical and medical device products. Failure to comply with applicable U.S. requirements may subject a company to a variety of administrative or judicial sanctions, such as the imposition by the FDA or an institutional review board (“IRB”) of a clinical hold, FDA refusal to approve pending new drug applications (“NDAs”) or supplements, withdrawal of approval, untitled or warning letters, product recalls, import alerts, product seizures, total or partial suspension of production or distribution, injunctions, fines, civil penalties, and criminal investigation, penalties, or prosecution.

Pharmaceutical Product Approval

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Product development for a new pharmaceutical product or certain changes to an approved pharmaceutical product in the United States typically involves:

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Completion of preclinical laboratory studies, formulation studies, and animal studies, some in compliance with the FDA’s Good Laboratory Practices (“GLP”) regulations, and the Animal Welfare Act administered and enforced by the United States Department of Agriculture;

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Submission to the FDA of an IND to support human clinical testing, which must become effective before clinical testing may commence;

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Approval by an IRB before each trial may be initiated at each clinical site;

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Performance of adequate and well-controlled clinical trials under protocols submitted to the FDA and reviewed and approved by each IRB, conducted in accordance with federal regulations and current Good Clinical Practices (“GCP”) to establish the safety and effectiveness of the drug for each indication for which FDA approval is sought;

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Submission of an NDA to the FDA that includes evidence that the drug is safe for use under the conditions in the proposed labeling and substantial evidence of effectiveness from results of clinical trials, as well as the results of preclinical testing, detailed information about the chemistry, manufacturing and controls, and proposed labeling and packaging for the product;

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Potential FDA audit of the preclinical and clinical trial sites that generated the data in support of the NDA;

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Satisfactory completion of FDA inspections of the manufacturing facilities at which the product candidate is produced to assess compliance with cGMP and to assure that the facilities, methods and controls are adequate; and

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FDA review and approval of the NDA, including agreement on post-marketing requirements or commitments, if applicable.

Satisfaction of FDA pre-market approval requirements typically takes many years and the actual time required may vary substantially based upon the type, complexity, and novelty of the product or disease.

Preclinical tests include laboratory evaluation of product chemistry, formulation, and toxicity, as well as animal studies to assess the characteristics and potential safety and efficacy of the product candidate. The conduct of some preclinical tests must comply with federal regulations and requirements, including as applicable, GLP and the Animal Welfare Act. The results of preclinical testing are submitted to the FDA as part of an IND along with other information, including information about product chemistry, manufacturing and controls, and a proposed clinical trial protocol. Additional preclinical tests, such as animal tests of reproductive toxicity and carcinogenicity, may continue after the IND is submitted. A 30-day waiting period after the submission of each IND is required prior to the commencement of clinical testing in humans. If the FDA has neither commented on nor questioned the IND within this 30-day period, the clinical trial proposed in the IND may begin.

Clinical trials involve the administration of the investigational drug product to healthy volunteers or patients under the supervision of a qualified investigator. Clinical trials must be conducted: (i) in compliance with federal regulations; (ii) in compliance with GCP, an international standard meant to protect the rights and health of patients and to define the roles of clinical trial sponsors, administrators, and monitors; as well as (iii) under protocols detailing the objectives of the trial, the parameters to be used in monitoring safety, and the effectiveness criteria to be evaluated. Each protocol involving testing on U.S. study participants and subsequent protocol amendments must be submitted to the FDA as part of the IND. Foreign studies conducted under an IND generally must meet the same requirements that apply to studies being conducted in the United States. The informed written consent of each study patient must be obtained before the patient may begin participation in the clinical trial. The study protocol, study plan, and informed consent forms for each clinical trial must be reviewed and approved by an IRB for each clinical site, and the study must be conducted under the auspices of an IRB for each trial site. Investigators and IRBs must also comply with FDA regulations and guidelines, including those regarding oversight of study participant informed consent, complying with the study protocol and investigational plan, adequately monitoring the clinical trial, and timely reporting of adverse events.

Clinical trials to support drug products for marketing approval are typically conducted in three sequential phases, but the phases may overlap. Phase 1 involves the initial introduction of the drug product into healthy human subjects or patients. In Phase 1 trials, the product is tested to assess safety, metabolism, pharmacokinetics, pharmacological actions, side effects associated with increasing doses, and, if possible, early evidence on effectiveness. Phase 2 usually involves trials in a limited patient population to determine the effectiveness of the drug for a particular indication, dosage tolerance, and optimal dosage, and to identify common adverse effects and safety risks. If a compound demonstrates evidence of effectiveness and an acceptable safety profile in Phase 2 evaluations, Phase 3 trials are undertaken to obtain the additional information about clinical efficacy and safety in a larger number of patients, typically at geographically dispersed clinical trial sites, to permit the FDA to evaluate the overall benefit-risk relationship of the drug and to provide adequate information for the labeling of the product. In most cases, the FDA requires two adequate and well-controlled Phase 3 clinical trials to demonstrate the efficacy of the drug product. Under certain circumstances, a single Phase 3 trial may be sufficient when either (1) the trial is a large, multicenter trial demonstrating internal consistency and a statistically very persuasive finding of a clinically meaningful effect on mortality, irreversible morbidity or prevention of a disease with a potentially serious outcome and confirmation of the result in a second trial would be practically or ethically impossible or (2) the single trial is supported by confirmatory evidence. Additionally, post-approval or Phase 4

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studies and trials, may be conducted after initial marketing approval. These studies are often used to gain additional information about use of the product for its approved indication, and may at times be required by the FDA.

The decision to suspend or terminate development of a product candidate may be made by either a health authority body, such as the FDA, by an IRB, or by a company for various reasons and during any phase of clinical trials. The FDA may order the temporary or permanent discontinuation of a clinical trial at any time or impose other sanctions if it believes that the clinical trial either is not being conducted in accordance with FDA requirements or presents an unacceptable risk to the clinical trial participants. In most cases, in addition to sponsor oversight, clinical trials are also overseen by an independent data safety monitoring board (“DSMB”), which is a separate, independent group of qualified experts organized by the trial sponsor to evaluate at designated points in time whether or not a trial may move forward and/or should be modified. These decisions are based on unblinded access to data from the ongoing trial and generally involve determinations regarding the benefit-risk ratio for study patients and the scientific integrity and validity of the clinical trial.

In addition, the manufacturer of an investigational drug in a Phase 2 or Phase 3 clinical trial for a serious disease or condition, or of an investigational drug that has received Fast Track designation or Breakthrough Therapy designation, is required to make available, such as by posting on its website, its policy on evaluating and responding to requests for expanded access to such investigational drug.

After completion of the required clinical testing, an application is prepared and submitted to the FDA to request marketing approval for the product candidate in specific indications. FDA approval of the drug product is required before marketing of the product may begin in the United States. The drug product must include all relevant results of preclinical, clinical, and other testing and a compilation of data relating to the product candidate’s pharmacology, chemistry, manufacture, and controls, including negative or ambiguous results as well as positive findings. To support marketing approval, the data submitted must be sufficient in quality and quantity to establish the safety and effectiveness of the product candidate to the satisfaction of the FDA. The cost of preparing and submitting a drug product application is substantial. Under the Prescription Drug User Fee Act (“PDUFA”), the submission of most drug product applications is subject to a substantial application user fee, and the applicant under an approved drug product is also subject to an annual program fee for each prescription product, subject to certain limited deferrals, waivers and reductions that may be available. These fees are typically increased annually. The FDA has 60 days from its receipt of an NDA to determine whether the application will be filed based on the agency’s threshold determination that it is sufficiently complete to permit substantive review. The FDA may refuse to file any NDA that it deems incomplete or not properly reviewable at the time of submission, in which case the NDA will have to be updated and resubmitted. Once the submission is filed, the FDA begins an in-depth review. The FDA has agreed to certain performance goals in the review of NDAs. The FDA’s PDUFA review goal is to review 90% of priority applications within six months of filing and 90% of standard applications within 10 months of filing. Priority review may be granted to an application for a product candidate that the FDA determines has the potential to treat a serious or life-threatening condition and, if approved, would be a significant improvement in safety or effectiveness compared to available therapies. The review process for both standard and priority review may be extended by the FDA for three additional months if the FDA determines that a major amendment has been submitted.

The FDA may also refer applications for drug candidates that present difficult questions of safety or efficacy, to an advisory committee—typically a panel that includes clinicians and other experts—for review, evaluation, and a recommendation as to whether the application should be approved. The FDA is not bound by the recommendation of an advisory committee, but it considers such recommendations carefully when making decisions. Before approving an NDA, the FDA will typically inspect one or more clinical sites to assure compliance with GCP. Additionally, the FDA will inspect the facility or the facilities at which the drug product is manufactured. The FDA will not approve the product unless compliance with cGMP is satisfactory and the NDA contains data that provides substantial evidence that the drug candidate is safe and effective in the intended indication.

After the FDA evaluates the NDA and the manufacturing facilities, it issues either an approval letter or a complete response letter. A complete response letter generally outlines the deficiencies in the submission and may require substantial additional testing, or information, in order for the FDA to reconsider the application. If and when those deficiencies have been addressed to the FDA’s satisfaction in a resubmission of the NDA, the FDA may issue an approval letter. The FDA has committed to reviewing such resubmissions in two or six months depending on the type of information included. Notwithstanding the submission of any requested additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval and deny approval of a resubmitted NDA.

An approval letter authorizes commercial marketing of the drug candidate with specific prescribing information for specific indications. As a condition of approval, the FDA may require a risk evaluation and mitigation strategy (“REMS,”) to help ensure that the benefits of the drug candidate outweigh the potential risks. REMS can include medication guides, communication plans for healthcare professionals, and elements to assure safe use (“ETASU”). ETASU can include, but are not limited to, special training or certification for prescribing or dispensing, dispensing only under certain circumstances, special monitoring, and the use of patient registries. The requirement for a REMS can materially affect the potential market and profitability of the product. Moreover, FDA may require post-approval studies or trials and heightened surveillance to characterize or monitor the product’s safety or efficacy.

Once granted, product approvals may be withdrawn if compliance with regulatory standards is not maintained or problems are identified following initial marketing. For example, quality control and manufacturing procedures must conform, on an ongoing basis, to cGMP requirements, and the FDA periodically inspects manufacturing facilities to assess compliance with cGMP. Accordingly, manufacturers must continue to spend time, money and effort to maintain cGMP compliance. Changes to some of the conditions established in an approved application, including changes in indications, labeling, or manufacturing processes or facilities, require submission and FDA approval of a

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new NDA or NDA supplement before the change can be implemented. An NDA supplement for a new indication typically requires clinical data similar to that in the original application, and the FDA uses the same procedures and actions in reviewing NDA supplements as it does in reviewing an NDA.

Expedited Programs

In the United States, a product may be granted Fast Track designation if it is intended for the treatment of a serious or life-threatening condition and nonclinical or clinical data demonstrate the potential to address unmet medical needs for such condition. With Fast Track designation, the sponsor may be eligible for more frequent opportunities to obtain the FDA’s feedback, and the FDA may initiate review of sections of an NDA before the application is complete. This rolling review is available if the applicant provides, and the FDA approves, a schedule for the remaining information. Even if a product receives Fast Track designation, the designation can be rescinded and provides no assurance that a product will be reviewed or approved more expeditiously than would otherwise have been the case, or that the product will be approved at all.

The FDA may designate a product candidate as a breakthrough therapy if it finds that the product candidate is intended, alone or in combination with one or more other product candidates or approved products, to treat a serious or life-threatening disease or condition, and preliminary clinical evidence indicates that the product candidate may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints. For product candidates designated as breakthrough therapies, more frequent interaction and communication between the FDA and the sponsor can help to identify the most efficient path for clinical development. Product candidates designated as breakthrough therapies by the FDA may also be eligible for six month priority review. The receipt of a breakthrough therapy designation for a product candidate may not result in a faster development process, review or approval compared to product candidates considered for approval under conventional FDA procedures and, in any event, does not assure ultimate approval by the FDA. In addition, the FDA may later decide that a product candidate that has been designated as a breakthrough therapy no longer meets the conditions for designation.

Accelerated approval under FDA regulations allows a product designed to treat a serious or life-threatening disease or condition that provides a meaningful therapeutic advantage over available therapies to be approved on the basis of either an intermediate clinical endpoint or a surrogate endpoint that is reasonably likely to predict clinical benefit. Approvals of this kind typically include requirements for confirmatory clinical trials to verify and describe the clinical benefit. These confirmatory trials must be completed with due diligence and the FDA is authorized to require that such post-approval studies be underway prior to approval or within a specific time period after the date accelerated approval is granted, and the agency has issued guidance as to what constitutes such a study being “underway.” The FDA is also required to specify conditions of any required post-approval confirmatory trial. Sponsors are required to submit progress reports for required post-approval studies and any conditions required by the FDA. The FDA may initiate enforcement action for the failure to conduct with due diligence a required post-approval trial, including a failure to meet any required conditions, which may include enrollment targets, the study protocol and study milestones, specified by the FDA, or to submit timely reports. All promotional materials for product candidates approved under accelerated approval regulations are subject to prior review by the FDA.

The FDA may grant priority review to a product candidate, which sets the target date for FDA action on the application at six months from FDA filing, or eight months from NDA submission. Priority Review may be granted where a product is intended to treat a serious or life-threatening disease or condition and, if approved, would provide a significant improvement in safety or effectiveness of the treatment, prevention, or diagnosis of that condition. If criteria are not met for Priority Review, the standard FDA review period is ten months from FDA filing or 12 months from NDA submission. Priority Review designation does not change the scientific/medical standard for approval or the quality of evidence necessary to support approval.

Orphan Drug Designation

Under the Orphan Drug Act, the FDA may grant orphan drug designation to drug candidate products intended to treat a rare disease or condition, meaning one that affects fewer than 200,000 individuals in the United States, or if it affects more than 200,000 individuals in the United States, there is no reasonable expectation that the cost of developing and making a product available in the United States for such disease or condition will be recovered from sales of the product in the United States.

After the FDA grants orphan drug designation, the generic identity of the drug product and its potential orphan use are disclosed publicly by the FDA. Orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. However, orphan drug designation does entitle a party to financial incentives, such as opportunities for grant funding towards clinical trial costs, tax credits for certain research and user fee waivers under certain circumstances. In addition, if a product receives the first FDA approval for the disease or condition for which it has orphan drug designation, the product is entitled to seven years of market exclusivity, which means the FDA may not approve any other application for the "same drug" for the same indication for a period of seven years, except in limited circumstances, such as a showing of clinical superiority over the product with orphan exclusivity. The FDA can revoke a product’s orphan drug exclusivity under certain circumstances, including when the product sponsor is unable to assure the availability of sufficient quantities of the product to meet patient needs. Orphan drug exclusivity does not prevent the FDA from approving a different drug for the same disease or condition, or the same drug for a different indication.

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Rare Pediatric Disease Priority Review Voucher Program

Under the Rare Pediatric Disease Priority Review Voucher program, the FDA may grant Rare Pediatric Disease designation for serious and life-threatening diseases that primarily affect children aged 18 years or younger and fewer than 200,000 individuals in the United States. The FDA may award a priority review voucher to the sponsor of an approved marketing application for a product that treats or prevents a Rare Pediatric Disease. The voucher entitles the sponsor to priority review of one subsequent marketing application.

A voucher may be awarded only for an application that:

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is a human drug application for the prevention or treatment of a Rare Pediatric Disease and does not contain an active ingredient (including any ester or salt of the active ingredient) that has been previously approved in any other application;

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FDA deems eligible for priority review;

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is an original NDA or Biologics License Application (“BLA”);

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relies on clinical data derived from studies examining a pediatric population and dosages of the drug intended for that population;

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does not seek approval for an adult indication in the original rare pediatric disease product application; and

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is approved after September 30, 2016.

Before NDA or BLA approval or licensure, the FDA may designate a product in development as a product for a rare pediatric disease, but such designation is not required to receive a voucher.

To receive a rare pediatric disease priority review voucher, a sponsor must notify the FDA, upon submission of the NDA or BLA, of its intent to request a voucher. If the FDA determines that the NDA or BLA is a rare pediatric disease product application, and if the NDA or BLA is approved or licensed, the FDA will award the sponsor of the NDA or BLA a voucher upon approval of the NDA or BLA. The FDA may revoke a rare pediatric disease priority review voucher if the product for which it was awarded is not marketed in the U.S. within 1 year of the product’s approval.

The voucher, which is transferable to another sponsor, may be submitted with a subsequent application and entitles the holder to priority review of that subsequent application. The sponsor submitting the priority review voucher must notify the FDA of its intent to submit the voucher with the application at least 90 days prior to submission of the application and must pay a priority review user fee in addition to any other required user fee. The FDA must take action on an application under priority review within six months of receipt of the application.

Currently, the rare pediatric disease priority review voucher program will sunset after September 30, 2029. FDA may not award any priority review vouchers under this program after September 30, 2029.

Disclosure of Clinical Trial Information

Sponsors of clinical trials of the FDA-regulated products are required to register and disclose certain clinical trial information. Information related to the product, patient population, phase of investigation, trial sites and investigators, and other aspects of the clinical trial is then made public as part of the registration. Sponsors are also obligated to discuss the results of their clinical trials after completion. Disclosure of the results of these trials can be delayed in certain circumstances for up to two years after the date of completion of the trial. Competitors may use this publicly available information to gain knowledge regarding the progress of development programs.

Pediatric Information

Under the Pediatric Research Equity Act (“PREA”), certain NDAs must include an assessment, based on clinical data, of the safety and effectiveness of the product candidate in relevant pediatric populations. The FDA may waive or defer the requirement for a pediatric assessment, either at a company’s request or by its own initiative, including waivers for certain products not likely to be used in a substantial number of pediatric patients. Products with orphan drug designation are exempt from these requirements for orphan-designated indications with no formal waiver process required. However, any original NDA submitted on or after August 18, 2020 for a new active ingredient must contain reports on molecularly targeted pediatric cancer investigations, unless the requirement is waived or deferred, if the drug that is the subject of the application is intended for the treatment of an adult cancer and is directed at a molecular target that the FDA has determined is substantially relevant to the growth or progression of a pediatric cancer. This requirement applies even if the adult cancer indication does not occur in the pediatric population, and even if the drug is for an adult indication for which orphan designation has been granted.

Patent Term Restoration

After approval, owners of relevant drug patents may apply for up to a five-year patent extension as compensation for patent term lost during product development and the FDA regulatory review process. The allowable patent term extension is calculated as one half of the

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drug’s testing phase—the time between the effective date of an IND and NDA submission—and all of the review phase—the time between NDA submission and approval, up to a maximum of five years. The time can be shortened if the FDA determines that the applicant did not pursue approval with due diligence. The total patent term after the extension may not exceed 14 years. Only one patent applicable to an approved product is eligible for the extension and the application for the extension must be submitted prior to the expiration of the patent. The United States Patent and Trademark Office (“USPTO”), in consultation with the FDA, reviews and approves the application for any patent term extension or restoration.

For patents that might expire during the application phase, the patent owner may request an interim patent extension. An interim patent extension increases the patent term by one year and may be renewed up to four times. For each interim patent extension granted, the post-approval patent extension is reduced by one year. The director of the USPTO must determine that approval of the drug covered by the patent for which a patent extension is being sought is likely. Interim patent extensions are not available for a drug for which an NDA has not been submitted.

Market Exclusivity

In the United States and elsewhere, certain regulatory exclusivities and patent rights can provide an approved drug product with protection from certain competitors’ products for a period of time and within a certain scope. In the United States, the Drug Price Competition and Patent Term Restoration Act of 1984 (“the Hatch-Waxman Act”) amended the FDCA to establish two abbreviated approval pathways for pharmaceutical products that are in some way follow-on versions of already approved products. In exchange, the Hatch-Waxman Act also provides certain periods of exclusivity for a branded drug product that would serve as a reference listing drug (“RLD”) for a generic drug applicant filing an abbreviated new drug application (“ANDA”) under section 505(j) of the FDCA or as a listed drug for an applicant filing an NDA under section 505(b)(2) of the FDCA. If such a product is a new chemical entity (“NCE”), meaning that the active moiety has never before been approved in any drug product, there is a period of five years from the product’s approval during which the FDA may not receive or file any ANDA or 505(b)(2) application for a drug with the same active moiety. However, there are circumstances under which the follow-on application can be submitted at four years, and there are provisions that operate to preclude approval of the application for an additional period of time. NCE exclusivity does not block approval of a “full” NDA (generally, an NDA in which the data are the sponsor’s or for which the sponsor has obtained a right of reference). A drug product that is not an NCE may qualify for a three-year period of exclusivity if its NDA contains new clinical data (other than bioavailability studies), derived from studies conducted by or for the sponsor, that were necessary for approval. In this instance, the three-year exclusivity period does not preclude receipt, filing or review of an ANDA or 505(b)(2) application; rather, the FDA is precluded from granting final approval to the ANDA or 505(b)(2) application during the three-year exclusivity period. This three-year exclusivity applies only to the conditions of approval that required submission of the clinical data.

Post-Approval Regulation

Once approved, drug products are subject to continuing extensive regulation by the FDA. If ongoing regulatory requirements are not met, or if safety problems occur after a product reaches market, the FDA may take actions to change the conditions under which the product is marketed, such as requiring labeling modifications, restricting distribution, or even withdrawing approval. In addition to FDA regulation, our business is also subject to extensive federal, state, local and foreign regulation.

Good Manufacturing Practices. Companies engaged in manufacturing drug products or their components, including contract manufacturers, must comply with applicable cGMP requirements, which include requirements regarding organization and training of personnel, building and facilities, equipment, control of components and drug product containers, closures, production and process controls, packaging and labeling controls, holding and distribution, laboratory controls and records and reports. The FDA inspects equipment, facilities and manufacturing processes before approval and conducts periodic re-inspections after approval. If, after receiving approval, a company makes a material change in manufacturing equipment, location, or process (all of which are, to some degree, incorporated in the NDA), additional regulatory review and approval may be required. Failure to comply with applicable cGMP requirements or the conditions of the product’s approval may lead the FDA to take enforcement actions, such as issuing a warning letter, or to seek sanctions, including fines, civil penalties, injunctions, suspension of manufacturing operations, imposition of operating restrictions, withdrawal of FDA approval, seizure or recall of products, and criminal prosecution.

Sales and Marketing. Once a product is approved, the advertising, promotion and marketing of the product will be subject to regulation, including with regard to promotion to healthcare practitioners, direct-to-consumer advertising, communications regarding unapproved uses, industry-sponsored scientific and educational activities and promotional activities involving the internet. In addition to FDA restrictions on marketing of pharmaceutical products, state and federal fraud and abuse laws have been applied to restrict certain marketing practices in the pharmaceutical industry. Failure to comply with applicable requirements in this area may subject a company to adverse publicity, investigations and enforcement action by the FDA, the Department of Justice, the Office of the Inspector General of the Department of Health and Human Services, and/or state authorities. This could subject a company to a range of penalties that could have a significant commercial impact, including civil and criminal fines and agreements that materially restrict the manner in which a company promotes or distributes drug products.

Other Requirements. Companies that manufacture or distribute drug products pursuant to approved NDAs must meet numerous other regulatory requirements, including adverse event reporting, submission of periodic reports, and record-keeping obligations.

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Medical Device Premarketing Authorization

Under the FDCA, unless a device is exempt or marketed under an FDA enforcement discretion, premarketing, clearance, authorization, or approval is required to commercially distribute a new medical device in the U.S. market. A new medical device could either be a device that has not previously received marketing authorization, clearance or approval in the US, or a previously authorized, cleared, or approved device that has been changed in such a way that would require a new marketing submission. Changes that could require a new marketing application submission for an existing device may relate to, but are not limited to, the intended use of the device, the indications for use, manufacturing, and technological characteristics or functionalities. The type of marketing authorization, clearance, or approval is generally linked to the classification of the device.

The FDA classifies medical devices into three classes based on risk. Regulatory control increases from Class I (lowest risk) to Class III (highest risk). As the risk of the device increases, so does FDA’s requirements for premarket review. Generally, all Class III and some Class II medical devices will require clinical testing to adequately demonstrate the safety and effectiveness of the device prior to FDA approval or clearance of the device for commercialization. The extent to which FDA is involved in the development of clinical trial protocols depends, in part, on whether the study is a significant risk (“SR”) study or a nonsignificant risk (“NSR”) study. Before testing begins, all clinical studies must obtain IRB approval and for SR medical devices an Investigational Device Exemption (“IDE”) must be obtained from the FDA. This exemption allows for clinical testing while ensuring participant safety and adherence to ethical standards. Though the regulatory requirements for an NSR study are less burdensome than those for a SR study, all clinical trials can be time consuming and costly and may not result in our desired outcomes.

Class I devices are those for which safety and effectiveness can be reasonably assured by adherence to a set of regulations referred to as general controls, which require compliance with the applicable portions of FDA’s Quality Management System Regulation (“QMSR”), facility registration and device listing, reporting of deaths, serious adverse events and certain malfunctions, which is referred to as medical device reporting, reporting of recalls (corrections and removals), and truthful and non-misleading labeling and promotional materials. Most Class I devices are exempt from the premarket notification requirements (i.e., 510(k)-exempt).

Laboratory Developed Devices

Government authorities in the United States and in other countries also regulate clinical laboratories and clinical lab tests, including LDTs. In order to perform clinical lab tests, report results and bill payers for these tests, clinical labs must obtain and maintain certification under the federal Clinical Laboratories Improvement Amendments (“CLIA”) regulations and they also may be subject to licensure and regulation under certain state laws. On May 6, 2024, the FDA issued a final rule amending the definition of an in vitro diagnostic (“IVD”) device to include tests manufactured by a clinical laboratory. This rule would have required LDTs to comply with the same general regulatory requirements as other medical devices. Two lawsuits challenging FDA’s authority to regulate LDTs—one by the American Clinical Laboratory Association and the other by the Association for Molecular Pathology—were filed in federal district courts in Texas in 2024 and were subsequently consolidated.. On March 31, 2025, the court issued an order vacating the final rule, thereby overturning the rulemaking’s associated requirements. The district court ruled that FDA lacks jurisdiction to regulate LDTs because they do not meet the definition of a medical device under the FDC Act. The government did not appeal.

Legislative proposals addressing the FDA’s oversight of LDTs have been previously introduced. For example, the VALID Act, introduced in 2021, in 2023 and again in 2025, would have established a new risk-based regulatory framework for in vitro clinical tests (“IVCTs”), a category which would have included IVDs, LDTs, collection devices and instruments used with such tests. It is unclear whether the court decision will renew interest in a legislative path for LDT regulation.

510(k) Clearance Process

Class II devices are those that are subject to general controls, as well as special controls, which can include performance standards, specialized labeling and post-market surveillance. Most Class II devices are subject to the premarket notification requirements or the 510(k) process. To obtain 510(k) clearance, a premarket notification, or 510(k), must be submitted to the FDA that demonstrates that the proposed medical device is substantially equivalent to a previously cleared medical device or a device commercially distributed prior to May 28, 1976, for which the FDA has not yet called for the submission of a PMA.

The previously cleared device is known as a predicate device. A proposed device is substantially equivalent to a predicate device if, with respect to the predicate device, it has the same intended use and has either (i) the same technological characteristics or (ii) different technological characteristics that do not raise different questions of safety and effectiveness.

If the FDA determines that a device is “not substantially equivalent” to a previously cleared device, for example, due to a finding of a lack of a predicate device, or that the proposed device has a new intended use or different technological characteristics that raise different questions of safety or effectiveness from the proposed predicate device, the device is automatically designated as a Class III device. The device sponsor must then fulfill more rigorous PMA requirements, or can request a risk-based classification determination for the device in accordance with the de novo process. As a result, FDA clearance requirements may extend the development process for a considerable length of time. If the FDA agrees that the proposed device is substantially equivalent to the predicate device proposed by the manufacturer, it will grant 510(k) clearance to commercially market the device.

De Novo Classification Process

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For novel medical devices that are low to moderate risk and are not substantially equivalent to a predicate device, a manufacturer may request a risk-based classification determination for the device in accordance with de novo classification process. This procedure allows a de novo requester whose novel device is automatically classified into Class III to request down-classification of its medical device into Class I or Class II on the basis that the device presents low or moderate risk, rather than requiring the submission and approval of a PMA. A requestor may submit a de novo request for classification after receiving a “not substantially equivalent” determination in response to a 510(k) submission or, absent the prior submission of a 510(k), when the sponsor determines that there is no legally marketed device upon which to base a determination of substantial equivalence.

The FDA may reject the de novo request if it identifies a legally marketed predicate device that would be appropriate for a 510(k) or determines that the device is not low to moderate risk or that general controls would be inadequate, and special controls cannot be developed, to control the risks. In the event the FDA determines that the data and information submitted demonstrate that general controls or general and special controls are adequate to provide reasonable assurance of safety and effectiveness, the FDA will grant the de novo request and a classification regulation will be established for the device type. When the FDA grants a de novo request for classification, the device is granted marketing authorization and can further serve as a predicate device for a future 510(k) submissions of that device type.

PMA Process

Class III devices include devices deemed by FDA to pose the greatest risk, such as life-supporting or life-sustaining devices, or implantable devices. With a few exceptions for certain types of devices classified into Class III that were in commercial distribution in the U.S. before May 28, 1976 and those placed into Class III by operation of law (i.e., novel devices not previously classified), Class III devices are subject to the pre-market approval (“PMA”) process which requires the manufacturer to independently demonstrate that a medical device is safe and effective for its intended use. This process is generally much more time-consuming and expensive than the 510(k) or de novo processes. The PMA process involves a complex and lengthy testing process that is subject to review by the FDA and may require several years to complete. The sponsor may need to first obtain an investigational device exemption (for significant risk devices), known as an IDE, in order to conduct extensive clinical testing of the device to obtain the necessary clinical data for submission to the FDA. Prior to obtaining approval, the manufacturer typically undergoes a bioresearch monitoring (“BIMO”) audit of the supporting clinical trial and a manufacturing audit, which may raise concerns that could lengthen the process and potentially raise unforeseen issues that undermine the approvability of the product. The FDA may also require review by an advisory panel, which can further lengthen the process.

The FDA will approve a PMA only if after evaluating the supporting technical data it finds that the PMA contains sufficient, valid scientific evidence to establish a reasonable assurance that the device is safe and effective for its intended use(s). This approval may be granted with post-approval requirements including inspection of manufacturing facilities, additional patient follow-up for an indefinite period of time, and/or a post-approval clinical study or studies.

Exempt Devices

If a manufacturer’s device falls into a generic category of Class I or Class II devices that FDA has exempted by regulation, a premarket notification is not required before marketing the device in the U.S. (most Class I devices, and some Class II devices, are 510(k)-exempt.) Manufacturers of such devices are required to comply with FDA’s general controls, including FDA’s establishment registration and device listing requirements. Some 510(k)-exempt devices are also exempt from QMSR requirements, except for the QMSR’s requirements relating to records and complaint files.

Device Modifications post-clearance or approval

Medical devices can be marketed only for the indications for which they are cleared, authorized or approved. After a device has received 510(k) clearance for a specific intended use, any change or modification that significantly affects its safety or effectiveness, such as a significant change in the design, materials, method of manufacture or intended use, may require a new 510(k) clearance or, depending on the modification, a de novo classification request or PMA approval. The determination as to whether or not a modification could significantly affect the device’s safety or effectiveness is initially left to the manufacturer using available FDA guidance; however, the FDA may review this determination to evaluate the regulatory status of the modified product at any time and may, if it disagrees with the manufacturer’s determination, require the manufacturer to cease marketing and possibly recall the modified device until a new 510(k) clearance, de novo authorization or PMA approval is obtained. The manufacturer may also be subject to enforcement action, including significant regulatory fines or penalties for marketing a modified device without the requisite pre-marketing authorization.

Postmarket Requirements

After a device is cleared or approved for commercial distribution, numerous federal and state regulatory requirements apply. These include device listing and establishment registration requirements, which help facilitate FDA inspections and other regulatory actions. Medical device establishments are subject to periodic inspection by the FDA for compliance with applicable FDA regulatory requirements, including the FDA's QMSR, which covers, among other things, the procedures and documentation of the risk management, design, testing, production, control, quality assurance, labeling, packaging, sterilization, storage and shipping of medical devices; the Medical Device Reporting regulation, which requires that manufacturers and initial importers report to the FDA if a device they manufactured or imported may have caused or contributed to a death or serious injury or malfunctioned in a way that would likely cause or contribute to a death or serious injury if the malfunction were to recur; and the Reports of Corrections and Removals regulation, which requires manufacturers and

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importers to report recalls and field corrective actions to the FDA if initiated to reduce a risk to health posed by the device or to remedy a violation of the FDCA.

In addition, labeling and promotional activities are subject to scrutiny by the FDA and, in certain circumstances, by the Federal Trade Commission. Medical devices that are approved, authorized or cleared by the FDA may not be promoted for unapproved, unauthorized or uncleared uses, otherwise known as “off-label” promotion. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses, and a company that is found to have improperly promoted off-label uses may be subject to significant liability, including substantial monetary penalties and criminal prosecution.

If the FDA believes that a company is not in compliance with applicable regulations, it may issue a non-public untitled letter or a public warning letter, institute proceedings to detain or seize products, issue a recall or market withdrawal order, impose operating restrictions including total or partial suspension of production or distribution, enjoin future violations, assess civil penalties against the company, its officers or its employees and may recommend criminal prosecution to the U.S. Department of Justice. Moreover, after clearance, authorization, or approval is given, if the product is shown to be hazardous or defective, the FDA has the power to withdraw the clearance, authorization, or approval, as the case may be, or require us to change the device, its manufacturing process or its labeling, to supply additional proof of the device’s safety and effectiveness or to recall, repair, replace the device or refund the cost of the medical device.

Other U.S. Healthcare Laws and Compliance Requirements

In the United States, activities of drug and device manufacturers are potentially subject to regulation by various federal, state and local authorities in addition to the FDA, including but not limited to, the Centers for Medicare and Medicaid Services (“CMS”), other divisions of the U.S. Department of Health and Human Services (e.g., the Office of Inspector General), the U.S. Department of Justice (“DOJ,”) and individual U.S. Attorney offices within the DOJ, and state and local governments. For example, sales, marketing and scientific/educational grant programs must comply with the anti-fraud and abuse provisions of the Social Security Act, the false claims laws, the privacy provisions of the Health Insurance Portability and Accountability Act and its implementing regulations (“HIPAA”), and similar state laws, each as amended. Clinical laboratory testing also must comply with the federal CLIA regulations and certain state licensure and other regulations, including restrictions related to billing for such tests.

The federal Anti-Kickback Statute prohibits, among other things, any person or entity, from knowingly and willfully offering, paying, soliciting or receiving any remuneration, directly or indirectly, overtly or covertly, in cash or in kind, to induce or in return for purchasing, leasing, ordering or arranging for the purchase, lease or order of any item or service reimbursable under Medicare, Medicaid or other federal healthcare programs. The term remuneration has been interpreted broadly to include anything of value. The Anti-Kickback Statute has been interpreted to apply to arrangements between pharmaceutical manufacturers on one hand and prescribers, purchasers, and formulary managers on the other. Liability under the Anti-Kickback Statute may be established without proving actual knowledge of the statute or specific intent to violate it. In addition, the government may assert that a claim including items or services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the federal civil False Claims Act. Although there are a number of statutory exceptions and regulatory safe harbors protecting some common activities from prosecution, the exceptions and safe harbors are drawn narrowly. Practices that involve remuneration that may be alleged to be intended to induce prescribing, purchasing or recommending a product or services may be subject to scrutiny if they do not qualify for an exception or safe harbor. Failure to meet all of the requirements of a particular applicable statutory exception or regulatory safe harbor does not make the conduct per se illegal under the Anti-Kickback Statute. Instead, the legality of the arrangement will be evaluated on a case-by-case basis based on a cumulative review of all of its facts and circumstances. Our practices may not in all cases meet all of the criteria for protection under a statutory exception or regulatory safe harbor.

The civil monetary penalties statute imposes penalties against any person or entity who, among other things, is determined to have presented or caused to be presented a claim to a federal health program that the person knows or should know is for an item or service that was not provided as claimed or is false or fraudulent.

The federal civil False Claims Act prohibits, among other things, any person or entity from knowingly presenting, or causing to be presented, claims for payment of government funds, including Medicare or Medicaid, that are false or fraudulent, or knowingly making, using, or causing to be made or used a false record or statement material to an obligation to pay or transmit money to the federal government, or knowingly concealing or improperly avoiding or decreasing an obligation to pay money to the federal government.. Recently, several pharmaceutical and other healthcare companies have been prosecuted under these laws for allegedly providing free product to customers with the expectation that the customers would bill federal programs for the product. Other companies have been prosecuted for causing false claims to be submitted because of the companies’ marketing of the product for unapproved, and thus generally non-reimbursable, uses. Clinical laboratories may face enforcement under the federal civil False Claims Act related to the claims submitted for payment of government funds, including Medicare or Medicaid. Actions under the False Claims Act may be brought by the federal government or as a qui tam action by a private individual in the name of the government.

HIPAA created federal criminal statutes that prohibit knowingly and willfully executing, or attempting to execute, a scheme to defraud or to obtain, by means of false or fraudulent pretenses, representations or promises, any money or property owned by, or under the control or custody of, any healthcare benefit program, including private third-party payors and knowingly and willfully falsifying, concealing or

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covering up by trick, scheme or device, a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services.

Also, many states have similar fraud and abuse statutes or regulations that apply to items and services reimbursed under Medicaid and other state programs, or, in several states, apply regardless of the payor. We may be subject to data privacy and security regulations by both the federal government and the states in which we conduct our business. HIPAA imposes requirements relating to the privacy, security and transmission of protected health information. In addition, state laws govern the privacy and security of personal information and health information in specified circumstances, many of which differ from each other in significant ways and may not have the same effect, thus complicating compliance efforts.

Additionally, the federal Physician Payments Sunshine Act within the Affordable Care Act (“ACA”), and its implementing regulations, require that certain manufacturers of drugs, devices, biological and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program (with certain exceptions) to report information related to certain payments or other transfers of value made or distributed to physicians, certain advanced practice professionals and teaching hospitals, or to entities or individuals at the request of, or designated on behalf of, the physicians, advanced practice professionals, and teaching hospitals and to report annually certain ownership and investment interests held by physicians and their immediate family members. The reported data are posted in searchable form on a public website on an annual basis. Failure to submit required information may result in civil monetary penalties.

In order to distribute products commercially, we must comply with state laws that require the registration of manufacturers and wholesale distributors of drug, device, and biological products in a state, including, in certain states, manufacturers and distributors who ship or sell products into the state even if such manufacturers or distributors have no place of business within the state. Some states also impose requirements on manufacturers and distributors to establish the pedigree of product in the chain of distribution, including some states that require manufacturers and others to adopt new technology capable of tracking and tracing product as it moves through the distribution chain. Several states have enacted legislation requiring pharmaceutical and biotechnology companies to establish marketing compliance programs, file periodic reports with the state, make periodic public disclosures on sales, marketing, pricing, clinical trials and other activities, and/or register their sales representatives, as well as to prohibit pharmacies and other healthcare entities from providing certain physician prescribing data to pharmaceutical and biotechnology companies for use in sales and marketing, and to prohibit certain other sales and marketing practices. All of our activities are potentially subject to federal and state consumer protection and unfair competition laws.

Coverage, Pricing and Reimbursement

In the United States, third-party payors include federal and state healthcare programs, private managed care providers, health insurers and other organizations. The process for determining whether a third-party payor will provide coverage for a product or service may be separate from the process for setting the price of a product or service, or for establishing the reimbursement rate that such a payor will pay for the product or service. Third-party payors may limit coverage to specific products on an approved list, also known as a formulary, which might not include all of the FDA-approved products for a particular indication. Third-party payors are increasingly challenging the price, examining the medical necessity and reviewing the cost-effectiveness of medical products, therapies and services, in addition to questioning their safety and efficacy.

Healthcare Reform

The ACA has substantially changed some aspects of healthcare financing and delivery by both governmental and private insurers. The ACA has affected existing government healthcare programs and resulted in the development of new programs.

Among the ACA provisions of importance to the pharmaceutical and biotechnology industries, in addition to those otherwise described above, are the following:

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an annual, nondeductible fee on any entity that manufactures or imports certain specified branded prescription drugs and biologic agents apportioned among these entities according to their market share in some government healthcare programs, that began in 2011;

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an increase in the statutory minimum rebates a manufacturer must pay under the Medicaid Drug Rebate Program, to 23.1% and 13% of the average manufacturer price for most branded and generic drugs, respectively, which rebate amount is no longer subject to a cap effective January 1, 2024;

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extension of manufacturers’ Medicaid rebate liability to covered drugs dispensed to individuals who are enrolled in Medicaid managed care organizations;

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expansion of eligibility criteria for Medicaid programs by, among other things, allowing states to offer Medicaid coverage to additional individuals beginning in 2014 and by adding new mandatory eligibility categories for individuals with income at or below 133% of the federal poverty level, thereby potentially increasing manufacturers’ Medicaid rebate liability;

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expansion of the entities eligible for discounts under the 340B drug discount program; and

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a new Patient-Centered Outcomes Research Institute to oversee, identify priorities in, and conduct comparative clinical effectiveness research, along with funding for such research.

The Tax Cuts and Jobs Act of 2017 eliminated certain requirements of the ACA, including the individual mandate. We cannot predict whether these challenges will continue or whether other proposals will be made or adopted, or what impact these efforts may have on us. It is possible that the ACA, as currently enacted or may be amended in the future, as well as other healthcare reform measures that may be adopted in the future, may result in additional reductions in Medicare and other healthcare funding, more rigorous coverage criteria, and new payment methodologies and in additional downward pressure on coverage and payment and the price that we receive for any approved product. Any reduction in reimbursement from Medicare or other government programs may result in a similar reduction in payments from private payors. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue, attain profitability or commercialize our products. We cannot be sure whether additional legislative changes will be enacted in the United States or outside of the United States, or whether regulatory changes, guidance or interpretations will be changed, or what the impact of such changes on the marketing approvals of our product candidates, if any, may be.

Other legislative changes relating to reimbursement have been adopted in the U.S. since the ACA was enacted. For example, the Budget Control Act of 2011, among other things, created the Joint Select Committee on Deficit Reduction to recommend to Congress proposals for spending reductions. The Joint Select Committee did not achieve a targeted deficit reduction, which triggered the legislation’s automatic reductions. In concert with subsequent legislation, this has resulted in aggregate reductions to Medicare payments to providers until 2032, unless additional Congressional action is taken.

The Protecting Access to Medicare Act of 2014 (“PAMA”) changed the methodology for setting Medicare reimbursement rates for clinical laboratory tests. Rates for new clinical laboratory tests are initially set by CMS, but ultimately the reimbursement rates are based on the weighted median of rates paid for the test by private payers, which labs are required report to CMS at specific intervals. Further federal changes that affect the coverage and reimbursement of clinical lab tests may be implemented in the future.

Further, the Inflation Reduction Act of 2022 (“IRA”), among other things, established a Medicare Part B and Part D inflation rebate scheme, under which, generally, manufacturers will owe rebates if the average sales price of certain Part B drugs or annual average manufacturer price of certain covered Part D drugs increases faster than the pace of inflation. The IRA also requires the U.S. Department of Health and Human Services (“HHS”) to directly negotiate the selling price of a statutorily specified number of drugs and biologics each year that CMS reimburses under Medicare Part B and Part D. The negotiated price may not exceed a statutory ceiling price. Only high-expenditure single-source drugs that have been approved for at least seven years (11 years for single-source biologics) can qualify for negotiation, with the negotiated price taking effect two years after the selection year. For 2026, the first year in which negotiated prices become effective, CMS selected 10 high-cost Medicare Part D products in 2023, negotiations began in 2024, and the negotiated maximum fair price for each product has been announced. In addition, CMS has selected and announced the negotiated maximum fair price for 15 additional Medicare Part D drugs, which will become effective for negotiated maximum fair pricing in 2027. For 2028, CMS selected an additional 15 drugs, comprised of drugs covered under Medicare Part D and, for the first time, drugs payable under Medicare Part B. For 2029 and subsequent years, 20 Part B or Part D drugs will be selected. Currently, a drug or biological product that has an orphan drug designation for only one rare disease or condition will be excluded from the IRA’s price negotiation requirements, but loses that exclusion if it has designations for more than one rare disease or condition, or if is approved for an indication that is not within that single designated rare disease or condition, unless such additional designation or such disqualifying approvals are withdrawn by the time CMS evaluates the drug for selection for negotiation. However, as a result of a statutory amendment enacted in July 2025, beginning with the 2028 negotiated price applicability year, a drug may be designated for more than one rare disease or condition and still be excluded from price negotiation, as long as the only approved indications are for such rare diseases or conditions. The IRA further made several changes to the Medicare Part D benefit, including a limit on annual out-of-pocket costs, and replacement of the coverage gap discount program with a new manufacturer discount program beginning in 2025. The IRA permits the Secretary of HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. Manufacturers that fail to comply with the IRA may be subject to various penalties, some significant, including civil monetary penalties.

Further, at the U.S. state level, legislatures are increasingly enacting laws and implementing regulations designed to control pharmaceutical and biological product pricing, including price or reimbursement constraints, discount requirements, marketing cost disclosure and price increase transparency reporting, and programs designed to encourage importation from other countries and bulk purchasing.

Government Price Reporting

Federal law requires manufacturers report the average sales price for certain drugs payable under Medicare Part B. Manufacturers calculate average sales price based on a statutorily defined formula as well as regulations and interpretations of the statute by CMS. CMS may use these submissions to determine payment rates for drugs under Medicare Part B. Moreover, manufacturers must pay refunds to Medicare for single source drugs or biologicals, or biosimilar biological products, reimbursed under Medicare Part B and packaged in single-dose containers or single-use packages, for units of discarded drug reimbursed by Medicare Part B in excess of 10 percent of total allowed charges under Medicare Part B for that drug. Manufacturers that fail to pay refunds could be subject to civil monetary penalties of 125 percent of the refund amount.

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Statutory or regulatory changes or CMS guidance could affect the pricing calculations for our product candidates, once approved and commercialized, and could negatively impact our results of operations. We further expect continued scrutiny on government price reporting and pricing more generally from Congress, agencies, and other bodies.

Employees and Human Capital

As of December 31, 2025, we had 28 full-time employees. Of these full-time employees, 10 were engaged in research and development and 18 were engaged in management, finance and administration. From time to time, we also employ independent contractors to support our operations. Our employees are not represented by any collective bargaining agreements and we have never experienced an organized work stoppage.

We believe that we must offer and maintain market competitive compensation and benefit programs for our employees in order to attract and retain qualified personnel. In addition to cash compensation, we provide equity compensation, a company-matched 401(k) Plan, healthcare and insurance benefits, health savings and flexible spending accounts, paid time off, family leave, and employee assistance programs.

Corporate Information

We were initially formed as a California general partnership in July 1996 and incorporated in the State of Delaware in May 1997. We were formerly known as Cytori Therapeutics, Inc., before that as MacroPore Biosurgery, Inc. and before that as MacroPore, Inc. On July 20, 2019, we changed our name from Cytori Therapeutics, Inc. to Plus Therapeutics, Inc.

Our corporate offices are located at 6420 Levit Green Boulevard, Suite 210, Houston, TX 77021. Our telephone number is (737) 255-7194. We maintain a website at the following address: www.plustherapeutics.com. The information on the Company’s website is not incorporated by reference in this report. We make available on or through our website certain reports and amendments to those reports that we file with or furnish to the SEC in accordance with the Securities Exchange Act of 1934, as amended (the “Exchange Act”). These include our Annual Reports on Form 10-K, our Quarterly Reports on Form 10-Q (“Form 10-Q”), and our Current Reports on Form 8-K. We make this information available on our website free of charge as soon as reasonably practicable after we electronically file the information with, or furnish it to, the SEC. In addition, we routinely post on the “Press Releases” page of our website news releases, announcements and other statements about our business and results of operations, some of which may contain information that may be deemed material to investors. Therefore, we encourage investors to monitor the “Press Releases” page of our website and review the information we post on that page.

The SEC maintains a website that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at the following address: http://www.sec.gov.

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Risk Factor Summary

Below is a summary of the principal factors that may affect our business, financial condition, and results of operations. This summary does not address all of the risks that we face. Additional risks not currently known to us or that we currently deem to be immaterial also may materially adversely affect our business, financial condition or results of operations in future periods. Further discussion of the risks summarized in this risk factor summary, and other risks that we face, can be found below under the heading “Risk Factors” and should be carefully considered, together with other information in this Form 10-K and our other filings with the Securities and Exchange Commission (“SEC”).

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We have incurred losses since inception, we expect to incur significant net losses in the foreseeable future and we may never become profitable and our operating results have been and will likely continue to be volatile.

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Uncertainties relating to our ability to fund our operations raises substantial doubt about our ability to continue as a going concern.

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We could be delisted from Nasdaq for failure to comply with the Minimum Stockholders’ Equity Requirement, the Minimum Bid Requirement or other applicable continued listing requirements and standards of Nasdaq, which would seriously harm the liquidity of our stock and our ability to raise capital.

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We will need substantial additional funding to develop our product candidates and conduct our future operations and to repay our outstanding debt obligations. If we are unable to obtain the funds necessary to do so, we may be required to delay, scale back or eliminate our product development activities or may be unable to continue our business operations.

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If we fail to maintain proper and effective internal controls, our ability to produce accurate financial statements on a timely basis could be impaired.

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Our future success is in large part dependent upon our ability to successfully develop our nanomedicine platform and commercialize rhenium (186Re) obisbemeda and 188RNL-BAM and any failure to do so could significantly harm our business and prospects.

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If we are unable to successfully partner with other companies to commercialize our product candidates, our business could materially suffer.

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Our success depends in substantial part on our ability to obtain regulatory approvals for our RNL product candidates. However, we cannot be certain that we will receive regulatory approval for these product candidates or our other product candidates.

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If we or any party to a key collaboration, licensing, development, acquisition or similar arrangement fail to perform material obligations, or commit a breach, under such arrangement, or any arrangement is terminated for any reason, there could be an adverse effect on our business.

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Reliance on government funding for our programs may impose requirements that limit our ability to take certain actions, and subject it to potential financial penalties, which could materially and adversely affect our business, financial condition and results of operations.

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If our competitors market or develop products that are marketed more effectively, approved more quickly than our product candidates, or demonstrated to be safer or more effective than our product candidates, our commercial opportunities could be reduced or eliminated.

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Product development involves a lengthy and expensive process, with an uncertain outcome. We may incur additional costs or experience delays in completing, or ultimately be unable to complete, the development and commercialization of our product candidates.

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Clinical trial results may fail to support approval of our product candidates.

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If third parties we engage are not able to successfully perform, we may not be able to successfully complete clinical development, obtain regulatory approval or commercialize our product candidates and our business could be substantially harmed.

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We may have difficulty enrolling, or fail to enroll patients in our clinical trials, which could delay or prevent clinical trials of our drug candidates.

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If a particular product candidate causes significant adverse events, then we may be unable to receive regulatory approval or market acceptance for such product candidate.

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If our product candidates and technologies receive regulatory approval but do not achieve broad market acceptance, especially by physicians, the revenue that we generate will be limited.

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All potential applications of our product candidates are investigational, which subjects us to development and marketing risks.

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We and our product candidates are subject to extensive regulation, and the requirements to obtain regulatory approvals in the United States and other jurisdictions can be costly, time-consuming, and unpredictable. If we or our partners are unable to obtain timely regulatory approval for our product candidates, our business may be substantially harmed.

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We will be subject to ongoing regulatory obligations and continued regulatory review, which may result in significant expense, and if we or our collaborators fail to comply with such requirements, regulatory agencies may take action against us or them, which could significantly harm our business.

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The future regulatory processes that will be applicable to Laboratory Developed Tests (LDTs) are uncertain and may prevent us from obtaining required authorizations for the commercialization of our products and/or introduce additional costs associated with those products.

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Adequate coverage and reimbursement from third party payors may not be available for our product candidates, which could diminish our sales or adversely affect our ability to sell our products profitably.

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Some intellectual property that we have in-licensed has been discovered through government funded programs and thus may be subject to federal regulations such as “march-in” rights, certain reporting requirements and a preference for U.S.-based companies. Compliance with such regulations may limit our exclusive rights, and limit our ability to contract with non-U.S. manufacturers.

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If we experience an interruption in supply from a material sole source supplier, our business may be harmed.

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We may engage in strategic transactions that could impact our liquidity, increase our expenses, and present significant distractions to our management.

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We must maintain quality controls and compliance with manufacturing standards.

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If we are unable to identify, hire and/or retain key personnel, we may not be able to sustain or grow our business.

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We face potential product liability exposure, and if successful claims are brought against us, we may incur substantial liability if our insurance coverage for those claims is inadequate.

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A failure to adequately protect health information could result in severe harm to our reputation and subject us to significant liabilities, each of which could have a material adverse effect on our business.

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We and our collaborators must comply with environmental laws and regulations, including those pertaining to use of hazardous and biological materials in our business, and failure to comply with these laws and regulations could expose us to significant liabilities.

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We may not be successful in our efforts to develop, fully utilize and monetize the CNSidediagnostic portfolio.

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Clinical laboratories are highly regulated and if we are unable to maintain compliance with these regulations, or if the regulations change in ways that make it more difficult or costly to comply, our financial condition and our business may be harmed.

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Our relationships with customers, healthcare providers, including physicians, and third-party payors are subject, directly or indirectly, to federal and state healthcare fraud and abuse laws, false claims laws, and other healthcare laws and regulations. If we are unable to comply, or have not fully complied, with such laws, we could face substantial penalties.

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The diagnostic testing industry is subject to rapid change, which could make our current or future products obsolete.

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Our success depends in part on our ability to protect our intellectual property.

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If we do not obtain patent term extension for any product candidates we may develop, our business may be materially harmed.

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We may not be able to protect our trade secrets.

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We may be subject to claims that our employees have wrongfully used or disclosed alleged trade secrets of their former employers.

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We may incur substantial costs as a result of litigation or other proceedings relating to patent and other intellectual property rights, and we may be unable to protect our rights to our product candidates and technology.

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If we are sued for infringing intellectual property rights of third parties, it will be costly and time consuming, and an unfavorable outcome in that litigation would have a material adverse effect on our business.

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Our stockholders may experience substantial dilution in the value of their investment if we issue additional shares of our capital stock.

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The market price of our common stock may be volatile and fluctuate significantly, which could result in substantial losses for stockholders.

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We may be or become the target of securities litigation, which is costly and time-consuming to defend.

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We may issue debt and equity securities or securities convertible into equity securities, any of which may be senior to our common stock as to distributions and in liquidation, which could negatively affect the value of our common stock.

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Our charter documents contain anti-takeover provisions.

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We presently do not intend to pay cash dividends on our common stock.

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If securities and/or industry analysts fail to continue publishing research about our business, if they change their recommendations adversely, or if our results of operations do not meet their expectations, our stock price and trading volume could decline.

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Increased information technology security threats and more sophisticated and targeted computer crime could pose a risk to our systems, networks, and products.

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Item 1A. Risk Factors

The risk factors described below, as well as statements described elsewhere in this Form 10-K, including our audited Financial Statements and the related notes and “Management’s Discussion and Analysis of Financial Conditions and Results of Operations,” or in other SEC filings, describe risks that could materially and adversely affect our business, financial condition, and results of operations, which could also cause the trading price of our equity securities to decline. These risks are not the only risks that we face. Our business, financial condition and results of operations could also be affected by additional factors that are not presently known to us or that we currently consider to be immaterial to our operations.

Risks Related to our Financial Position and Capital Requirements

We have incurred losses since inception, we expect to incur significant net losses in the foreseeable future and we may never become profitable and our operating results have been and will likely continue to be volatile.

We have generated negative cash flows from operations and have incurred net operating losses each year since we started business. For the year ended December 31, 2025, we incurred net losses of $22.4 million and our net cash used in operating activities was $20.8 million. As of December 31, 2025, our accumulated deficit was $515.9 million. We expect to continue to incur net losses and negative cash flow from operating activities for at least the next twelve months. As our focus on development of nanomedicine and the development of therapeutic applications has increased, losses have resulted primarily from expenses associated with research and development and clinical trial-related activities, as well as general and administrative expenses. We expect to continue operating in a loss position and expect that recurring operating expenses will be at higher levels for the year ending December 31, 2026 as we perform clinical trials and other development activities for our nanomedicine product candidates.

Our ability to generate sufficient revenue from any of our products, product candidates or technologies to achieve profitability will depend on a number of factors including, but not limited to:

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our ability to manufacture, test and validate our product candidates or clinical tests in compliance with applicable laws and as required for submission to applicable regulatory bodies;

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our or our partners’ ability to successfully complete clinical trials of our product candidates;

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our ability to obtain necessary regulatory approvals for our product candidates;

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our or our partners’ ability to negotiate and receive favorable reimbursement for our product candidates, including for our product candidates that have been granted or may be granted orphan drug status or otherwise command currently anticipated pricing levels;

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our ability to negotiate favorable arrangements with third parties to help finance the development of, and market and distribute, our products and product candidates;

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the degree to which our approved products are accepted in the marketplace; and

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our success at commercializing our CNSideTM Portfolio.

Because of the numerous risks and uncertainties associated with our commercialization and product development efforts, we are unable to predict the extent of our future losses or when or if we will become profitable and it is possible we will never become profitable. If we do not generate significant sales from any of our product candidates that receive regulatory approval, there would be a material adverse effect on our business, results of operations, financial condition and prospects, which in turn could result in our inability to continue operations.

Our prospects must be evaluated in light of the risks and difficulties frequently encountered by emerging companies and particularly by such companies in rapidly evolving and technologically advanced biotech, pharmaceutical and medical device fields. In addition, our budgeted expense levels are based in part on our expectations concerning future research and development activities. We may be unable to reduce our expenditures in a timely manner to compensate for any unexpected events. Accordingly, unexpected events could have an immediate and material impact on our business and financial condition. From time to time, we have tried to update our investors’ expectations as to our operating results. If we revise any timelines we may give with respect to our clinical trials, it could materially harm our reputation and the market’s perception of us and could cause our stock price to decline.

Uncertainties relating to our ability to fund our operations raises substantial doubt about our ability to continue as a going concern.

We received net proceeds of approximately $13.3 million, in the public offering that closed on January 15, 2026, allowing the Company to maintain a cash runaway until approximately 2027. As of December 31, 2025, we had an accumulated deficit of approximately $515.9 million, working capital of approximately $2.9 million, and approximately $13.1 million of cash and cash equivalents, restricted cash, and short-term investments to fund our operations and capital requirements. Absent further actions, these matters raise substantial doubt about our ability to continue as a going concern.

We have a history of generating losses and negative cash flows from operations. Our financial statements have been prepared under the assumption that we will continue as a going concern for the next twelve months. Our ability to continue as a going concern is dependent upon our ability to obtain additional debt, equity or other financing. Furthermore, we also could be required to seek funds through

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arrangements with collaborative partners or otherwise that may require us to relinquish rights to some of our intellectual property or product candidates or otherwise agree to terms unfavorable to us.

If we are unsuccessful in our efforts to raise any such additional capital, we would be required to take actions that could materially and adversely affect our business, including significant reductions in our research, development and administrative operations (including reduction of our employee base), possible surrender or other disposition of our rights to some technologies or product opportunities, delaying of our clinical trials or curtailing or ceasing operations.

We could be delisted from Nasdaq for failure to comply with the Minimum Stockholders’ Equity Requirement, the Minimum Bid Requirement or other applicable continued listing requirements and standards of Nasdaq, which would seriously harm the liquidity of our stock and our ability to raise capital.

Our common stock is currently listed on The Nasdaq Capital Market. In order to maintain that listing, we must maintain compliance with Nasdaq’s continued listing requirements and standards. There can be no assurances that we will be able to comply with the applicable listing requirements and standards of Nasdaq.

Minimum Stockholders’ Equity Requirement

In March 2024, we received notice from the Listing Qualifications staff of Nasdaq (the “Staff”), notifying us that we no longer maintained at least $2.5 million in stockholders’ equity, as required under Nasdaq Listing Rule 5550(b)(1) (the “Minimum Stockholders’ Equity Requirement”), and also did not meet any other alternative standard. On October 22, 2024, we held our first hearing before a Nasdaq panel, as a result of which we received additional time, or until March 4, 2025, to regain compliance.

A second hearing was held on July 15, 2025. On July 22, 2025, the panel for our second hearing issued a decision granting our request for continued listing on Nasdaq, subject to us demonstrating compliance with (1) the Minimum Stockholders’ Equity Requirement by August 14, 2025; and (2) the Minimum Bid Requirement (as defined below) by September 8, 2025. On August 22, 2025, we received a letter (the “August 2025 Letter”) from Nasdaq confirming our compliance with Nasdaq Listing Rule 5550(b). Specifically, the August 2025 Letter confirmed that we were in compliance with both (1) Nasdaq Listing Rule 5550(b)(2), which requires a market value of listed securities of at least $35 million and (2) the alternative stockholders’ equity threshold under Nasdaq Listing Rule 5550(b)(1), which is the Minimum Stockholders’ Equity Requirement. The August 2025 Letter also provided that, solely with respect to the Minimum Stockholders’ Equity Requirement, we remain subject to a one-year panel monitoring period, through August 22, 2026. If, within that one-year monitoring period, the Staff determines that we no longer satisfy the Minimum Stockholders’ Equity Requirement (and we are not then in compliance with one of the alternative standards under Nasdaq Listing Rule 5550(b)), we will not be permitted to provide the Staff with a plan of compliance and the Staff is not permitted to grant additional time to regain compliance with the Minimum Stockholders’ Equity Requirement nor will we be afforded an applicable cure or compliance period. Instead, the Staff will issue a delist determination letter, and we will have an opportunity to request a new hearing before the Nasdaq Hearings Panel, which request would stay any further action by the Staff pending the ultimate outcome of the hearing.

Minimum Bid Requirement

On May 16, 2025, we received notice from Nasdaq that, because the closing bid price for our common stock had fallen below $1.00 per share for 30 consecutive business days, we no longer complied with the minimum bid price requirement pursuant to Nasdaq Listing Rule 5550(a)(2) (the “Minimum Bid Requirement”). We were provided an initial compliance period of 180 calendar days, or until November 12, 2025, to regain compliance with the Minimum Bid Requirement. To regain compliance, the closing bid price of our common stock must meet or exceed $1.00 per share for a minimum of 10 consecutive business days prior to November 12, 2025.

On November 13, 2025, we received a second letter from the Nasdaq Staff advising that we had been granted an additional 180 calendar days, or until May 11, 2026, to regain compliance with the Minimum Bid Requirement, in accordance with Nasdaq Listing Rule 5810(c)(3)(A).

We intend to continue to actively monitor the closing bid price of our common stock and will evaluate available options to regain compliance with the Minimum Bid Requirement. Specifically, we have confirmed to Nasdaq that, if necessary, we will implement a reverse stock split of our outstanding common stock to attempt to regain compliance. If we do not regain compliance within the additional compliance period, Nasdaq will provide notice that our common stock will be subject to delisting. We would then be entitled to appeal that determination to a Nasdaq hearings panel. There can be no assurance that we will regain compliance with the Minimum Bid Requirement during the 180-day additional compliance period or maintain compliance with the other Nasdaq listing requirements.

Potential Consequences of Delisting

There is no assurance that we will be able to meet Nasdaq’s listing requirements or comply with the requisite Nasdaq requirements to maintain our listing of common stock on Nasdaq. In the event that our common stock is delisted from Nasdaq, as a result of our failure to comply with the Minimum Stockholders’ Equity Requirement or the Minimum Bid Requirement or as a result of our failure to continue to comply with any other requirement for continued listing on Nasdaq, and we are not able to list our securities on Nasdaq or any other national securities exchange, we could face significant material adverse consequences, including:

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a decline of the market price of our common stock;

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a limited availability of market quotations for our common stock;

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reduced liquidity for our common stock;

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a determination that our common stock is a “penny stock,” which will require brokers trading in our common stock to adhere to more stringent rules and possibly result in a reduced level of trading activity in the secondary trading market for our securities;

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a limited amount of news and analyst coverage for us;

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a decreased ability to issue additional securities or obtain additional financing in the future; and

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the incurring of additional costs under state blue sky laws in connection with any sales of our securities.

As of the date of this Annual Report, we require additional funding to develop our product candidates, conduct future operations, and repay our outstanding obligations. If we are unable to obtain the funds necessary to do so because our common stock is not listed on any national securities exchange, we may be required to delay, scale back or eliminate our product development activities, and we may be unable to continue our business operations.

If our common stock is delisted by Nasdaq, our common stock may be eligible to trade on an over-the-counter quotation system where an investor may find it more difficult to sell our stock or obtain accurate quotations as to the market value of our common stock. In the event our common stock is delisted from Nasdaq, we may not be able to list our common stock on another national securities exchange or obtain quotation on an over-the-counter quotation system.

We will need substantial additional funding to develop our product candidates and conduct our future operations and to repay our outstanding debt obligations. If we are unable to obtain the funds necessary to do so, we may be required to delay, scale back or eliminate our product development activities or may be unable to continue our business operations.

We have had, and we will continue to have, an ongoing need to raise additional cash from outside sources to continue funding our operations, including our continuing substantial research and development expenses and potential commercialization activities. We do not currently believe that our cash balance will be sufficient to fund the development and marketing efforts required to reach profitability without raising additional capital from accessible sources of financing in the near future. Our future capital requirements will depend on many factors, including:

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our ability to raise capital to fund our operations on terms acceptable to us, or at all;

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our perceived capital needs with respect to our development programs, and any delays in, adverse events and excessive costs of such programs beyond what we currently anticipate;

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our ability to establish and maintain collaborative and other arrangements with third parties to assist in bringing our product candidates to market and the cost of such arrangements at the time;

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costs associated with operating at our Houston, Texas facility;

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the cost of manufacturing our product candidates, including compliance with good manufacturing practices applicable to our product candidates;

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expenses related to the establishment of sales and marketing capabilities for product candidates awaiting approval or products that have been approved;

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competing technological and market developments; and

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our ability to introduce and sell new products.

The amount and timing of our future funding requirements will depend on many factors, including the pace and results of our clinical development efforts.

We have secured capital historically from grant revenue, collaboration proceeds, and debt and equity offerings. To obtain additional capital, we may pursue debt and/or equity offering programs, strategic corporate partnerships, state and federal development programs, licensing arrangements, and sales of assets or debt or equity securities. We cannot be certain that additional capital will be available on terms acceptable to us, or at all. If we are unsuccessful in our efforts to raise any such additional capital, we may be required to take actions that could materially and adversely harm our business, including a possible significant reduction in our research, development and administrative operations (including reduction of our employee base), the surrender of our rights to some technologies or product opportunities, delay of our clinical trials or regulatory and reimbursement efforts, or curtailment or cessation of operations.

Depending on the type and the terms of any financing we pursue, stockholders’ rights and the value of their investment in our common stock could be reduced. A financing could involve one or more types of securities including common stock, preferred stock, convertible debt or warrants to acquire common stock. These securities could be issued at or below the then prevailing market price for our common stock or with terms or conditions that provide new investors with rights that are superior to those held by our existing stockholders or that have a negative impact on the value of securities held by our existing stockholders. For example, the terms of our recent offerings resulted in substantial dilution to our existing stockholders. In addition, if we issue secured debt securities, the holders of the debt would have a

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claim to our assets that would be prior to the rights of stockholders until the debt is paid. Interest on these debt securities would increase costs and negatively impact operating results. If the issuance of new securities results in diminished rights to holders of our common stock, the market price of our common stock could be negatively impacted.