Aprea Therapeutics, Inc._December 31, 2025

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

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

For the year ended December 31, 2025

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

For the transition period fromto

Commission File Number 001-39069

Aprea Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Doylestown, Pennsylvania (Zip code)

(Address of principal executive offices)

(215) 948-4119

(Registrant's telephone number, including area code)

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

Name of exchange

Title of each class Trading Symbol on which registered:

Common stock, par value $0.001 per share APRE The NASDAQ Stock Market LLC

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 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 the 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 by 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 voting and non-voting common equity held by non-affiliates of the registrant as of June 30, 2025 was approximately $8.6 million.

There were 11,452,452 shares of the registrant’s common stock, $0.001 par value, outstanding as of March 16, 2026.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s definitive proxy statement for its 2025 Annual Meeting of Stockholders (the “Proxy Statement”), to be filed within 120 days of the registrant’s fiscal year ended December 31, 2025, are incorporated by reference in Part III of this Annual Report on Form 10-K. Except with respect to information specifically incorporated by reference in this Annual Report on Form 10-K, the Proxy Statement is not deemed to be filed as part of this Annual Report on Form 10-K.

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Aprea Therapeutics, Inc.

Annual Report on Form 10-K

For the Year Ended December 31, 2025

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Page

PART I

Item 1. Business 5

Item 1A. Risk Factors 48

Item 1B. Unresolved Staff Comments 110

Item 1C. Cybersecurity 110

Item 2. Properties 111

Item 3. Legal Proceedings 111

Item 4. Mine Safety Disclosures 111

PART II

Item 6. [Reserved] 113

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 126

Item 8. Financial Statements and Supplementary Data F-1

Item 9A. Controls and Procedures 125

Item 9B. Other Information 126

PART III

Item 10. Directors, Executive Officers and Corporate Governance 126

Item 11. Executive Compensation 126

Item 14. Principal Accounting Fees and Services 126

PART IV

Item 15. Exhibits, Financial Statement Schedules 126

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K includes statements that are, or may be deemed, “forward-looking statements.” In some cases, these forward-looking statements can be identified by the use of forward-looking terminology, including the terms “believes,” “estimates,” “anticipates,” “expects,” “plans,” “intends,” “may,” “designed,” “would,” “could,” “might,” “will,” “should,” “approximately” or, in each case, their negative or other variations thereon or comparable terminology, although not all forward-looking statements contain these words. They appear in a number of places throughout this Annual Report on Form 10-K and include statements regarding our current intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things, our ongoing and planned clinical trials, including for APR-1051 and ATRN-119, our ongoing and planned development, prospects for commercialization, and market uptake of our potential product candidates, the strength and breadth of our intellectual property, the timing of and our ability to make regulatory filings and obtain and maintain regulatory approvals for our product candidates, the legal and regulatory landscape impacting our business, the degree of clinical utility of our product candidates, particularly in specific patient populations, expectations regarding clinical trial data, our development and validation of manufacturing capabilities, our results of operations, financial condition, liquidity, prospects, growth and strategies, the length of time that we will be able to continue to fund our operating expenses and capital expenditures, our expected financing needs and sources of financing, the industry in which we operate and the trends that may affect the industry or us.

By their nature, forward-looking statements involve risks and uncertainties because they relate to future events, competitive dynamics, and healthcare, regulatory and scientific developments and depend on economic circumstances that may or may not occur in the future or may occur on longer or shorter timelines than anticipated. We caution you that forward-looking statements are not guarantees, or predictive, of future performance and that our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate may differ materially from the forward-looking statements contained in this Annual Report on Form 10-K.

Some of the factors that we believe could cause actual results to differ from those anticipated or predicted include

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● developments relating to our competitors and our industry;

● our expectations regarding our future costs of goods;

● the impact of government laws and regulations;

● our financial performance; and

Any forward-looking statements that we make in this Annual Report on Form 10-K speak only as of the date of such statement, and we undertake no obligation to update such statements to reflect events or circumstances after the date of this Annual Report on Form 10-K. You should also read carefully the factors described in the “Risk Factors” included in Part I, Item 1A of this Annual Report to better understand significant risks and uncertainties inherent in our business and underlying any forward-looking statements. As a result of these factors, we cannot assure you that the forward-looking statements in this Annual Report on Form 10-K will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified timeframe, or at all.

This Annual Report on Form 10-K includes statistical and other industry and market data that we obtained from industry publications and research, surveys and studies conducted by third parties. Industry publications and third-party research, surveys and studies generally indicate that their information has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. While we believe these industry publications and third-party research, surveys and studies are reliable, we have not independently verified such data.

We qualify all of our forward-looking statements by these cautionary statements. In addition, with respect to all of our forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995.

This Form 10-K may include trademarks, tradenames, and service marks that are the property of other organizations. Solely for convenience, our trademarks and tradenames referred to in this Form 10-K may appear without the ® and TM symbols, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights, or the right of the applicable licensor to these trademarks and tradenames.

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PART I

Item 1. Business

Overview

We are a clinical-stage precision medicine oncology company focused on the discovery and development of targeted therapies for patients with biomarker-defined cancers. Our approach focuses on matching treatments to specific cancer-related genetic mutations to potentially maximize effectiveness and minimize side effects. Specifically, we develop small molecule inhibitors designed to exploit genetic mutations in cancer to widen the therapeutic window and intended to make treatments more effective at destroying cancer cells while sparing healthy tissue. We have assembled a team with extensive experience in the discovery, development, and commercialization of oncology drugs to support our mission of developing novel synthetic lethality-based cancer therapeutics.

Aprea Therapeutics AB was originally incorporated in 2002 and commenced principal operations in 2006. On September 20, 2019, we consummated a reorganization, pursuant to which all of the issued and outstanding stock and options of Aprea Therapeutics AB were exchanged for common stock, preferred stock or options, as applicable, of Aprea Therapeutics, Inc. As a result, Aprea Therapeutics AB became a wholly-owned subsidiary of Aprea Therapeutics, Inc.

Prior to our acquisition of Atrin Pharmaceuticals Inc. (“Atrin”) in May 2022, we were engaged in the clinical development of cancer therapeutics that related to the mutant p53 tumor suppressor protein. Following our acquisition of Atrin, we enhanced our pipeline and shifted the focus of our activities to the assets acquired from Atrin and those developed in house.

We believe that precision medicine has the potential to impact patients’ lives in a wide range of cancer types. Genomic instability is the hallmark or cancer. When a gene pathway is damaged or fails, related genes make up for its loss of function. Our approach is to inhibit these make up genes, thereby specifically killing cancer cells with defined mutations. This approach is called synthetic lethality. Using synthetic lethality, our product candidates are designed to selectively kill cancer cells while minimizing the effect on normal, unmutated cells, decreasing the toxicity usually associated with cancer treatment. We aspire to become a leader in this emerging field and are establishing a pipeline of clinical and preclinical programs that we believe may have broad applications to cancer treatment.

WEE1 Inhibitor: APR-1051

In this program, we are targeting WEE1, a kinase that is a key regulator of multiple phases of the cell cycle. Our lead WEE1 inhibitor product candidate is APR-1051. In March 2024, our investigational new drug (“IND”) application for APR-1051 (IND 169359) went into effect and in the second quarter of 2024 we enrolled the first patient into ACESOT-1051, our Phase 1 dose escalation study. A total of 9 cohorts are planned for ACESOT-1051 that will evaluate doses of 10 mg to 300 mg once daily. As of March 2, 2026, we are enrolling cohort 8 for ACESOT-1051 to evaluate a dose of 220 mg once daily. Preliminary results provide early clinical proof-of-concept of APR-1051. A potential dose-response trend was observed, with increasing single-agent activity across the 70 mg, 100 mg, 150 mg and 220 mg cohorts. On January 29, 2026, we announced the first unconfirmed partial response (uPR) observed in a patient enrolled in the ongoing Phase 1 ACESOT-1051 dose-escalation study: a patient with PPP2R1A-mutated uterine serous carcinoma, a form of endometrial cancer, treated at the 150 mg dose level of APR-1051. At the protocol-defined 8-week first imaging assessment, the patient achieved a 50% reduction in target lesion size per RECIST v1.1 criteria, along with a marked reduction in cancer antigen 125 (CA-125) levels, from 732 to 70 U/mL. CA-125 is a well-recognized tumor marker in endometrial cancer. On February 18, 2026, we announced the second uPR observed in a patient with PPP2R1A-mutated endometrial cancer, treated at the 220 mg dose level: at the first imaging assessment the patient achieved a 50% reduction in target lesion size, along with a marked decline in CA-125 from 362 at baseline to 47 U/mL, further supporting the anti-tumor activity of APR-1051.In addition, preliminary results from the ACESOT-1051 study indicate that APR-1051 has been safe and well-tolerated to date, supporting our development strategy to differentiate WEE1 inhibition through a potentially improved therapeutic index. Low therapeutic index has been a major hurdle in the development of WEE1 inhibitors. Active enrollment is ongoing at three sites in the U.S. (NCT06260514) with additional

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sites planned. We anticipate additional open-label safety/efficacy data to be available in the second quarter of 2026. We expect to complete dose-escalation in the third quarter of 2026.

ATR Inhibitor: ATRN-119 (Mosipasertib)

Our second clinical-stage synthetic lethality product candidate is ATRN-119, an oral small molecule inhibitor of ataxia telangiectasia and Rad3-related, or ATR. The ATR kinase is a master regulator of the DNA damage response, with key roles in cell cycle control and DNA repair following replication stress. We have developed ATRN-119, the first oral macrocyclic ATR inhibitor to enter clinical trials. On October 15, 2025, we announced that we had determined the recommended Phase 2 dose (RP2D) of 1,100 mg once daily for ATRN-119 in the ABOYA-119 Phase 1/2a dose-escalation study, in patients with advanced solid tumors. Building on the completion of dose escalation, we are considering further ATRN-119 development in combination approaches that could expand its therapeutic potential. We believe ATRN-119's mechanism of action, favorable safety profile, and pharmacologic characteristics make it an ideal candidate for combination with other anti-cancer therapies, including radiation therapy, antibody-drug conjugates (ADCs) and immune checkpoint inhibitors. We are currently in discussions with leading academic centers to explore combining ATRN-119 with radiation in patients with human papillomavirus–positive (HPV+) head and neck cancer. Additional investigator-led studies evaluating ATRN-119 in combination with an I/O agent and ADCs are also being explored. As part of this strategic focus, we have paused further enrollment in both once daily and twice daily monotherapy dosing arms of ABOYA-119 and started an orderly wind-down of certain clinical trial site activities associated with the monotherapy arms as we explore ATTN-119 in potential combination approaches.

P53 Reactivator: APR-246 (eprenetapopt)

We do not currently have any ongoing clinical trials involving our reactivator of mutant p53, which we were previously engaged in prior to our acquisition of Atrin.

DYRK1 Inhibitor: APR-1602

We also have an early-stage program, APR-1602, a macrocyclic DYRK1A/B inhibitor, that will be ready to enter IND-enabling studies in the fourth quarter of 2026.

Our Pipeline

We are focused on delivering breakthrough therapies for cancers with high unmet medical need. Our two lead programs are APR-1051, a WEE1 inhibitor, and ATRN-119, an ATR inhibitor. Both compounds were discovered internally and are being developed by our experienced team of chemists, scientists, and clinicians. We believe our programs have the potential to advance innovative treatments for cancer patients with unmet medical needs and deliver meaningful impact to patients and generate long-term value for shareholders. In addition, our pipeline also includes a DYRK1 inhibitor, APR-1602, which is a preclinical program.

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Our strategy

We aspire to be a leader in the emerging field of synthetic lethality-based precision oncology therapeutics. The key elements of our strategy are to:

Our Approach

Our approach to the development of novel cancer therapies is based on a powerful biological phenomenon known as synthetic lethality. Synthetic lethality represents an emerging strategy to treat a broad spectrum of cancers that currently

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lack effective treatments. Our focus is the application of synthetic lethality in the DDR pathway to effect selective killing of cancer cells while sparing normal cells.

Background on Synthetic Lethality

First described in 1922, the concept of synthetic lethality describes biological observations wherein mutations in a pair of genes result in cell death, but mutations in either gene alone do not. Cancer is a genetically driven collection of diseases in which mutations in the genome allow cells to bypass the normal checks and balances that control cell replication. Frequently, these mutations occur in genes that have critical roles in metabolism and DNA repair. While mutations in such genes may permit cells to survive, it is possible that mutation in a second gene, or loss of function resulting from pharmacologic inhibition, may trigger cancer cell death if the two genes are synthetically lethal.

The first clinical validation of synthetic lethality for cancer treatment was with BRCA1/2 mutations and PARP inhibition. BRCA1 and BRCA2 are proteins with key roles in the repair of DNA double-strand breaks (DSBs), one of the most lethal DNA lesions. BRCA1/2 mediate homologous recombination (HR), the major mechanism of DSB repair. When there is a loss of function in BRCA1/2, then cells become more dependent on PARP to prevent the formation of DSBs. If in this context PARP function is inhibited, then BRCA1/2 mutated cancer cells die. In other words, BRCA1/2 mutation and PARP inhibition are synthetically lethal. In contrast, normal cells with functional BRCA1/2 are spared. There are currently multiple PARP inhibitors approved by FDA for the treatment of various solid tumors with BRCA1/2 dysfunction.

Background on DDR

Cells are continuously exposed to endogenous and exogenous stress that can lead to DNA damage. To counter this lethal threat, cells have mechanisms to detect DNA damage, activate the appropriate repair pathway or, if irreparable, induce cell cycle arrest or apoptosis. These DDR processes are vital for cell survival.

Cancer cells rely on various alternative pathways to repair and resist DNA damage and replication stress. Many of these DDR-related genes are mutated across cancers, as loss of the DDR pathway allows cancer cells to rapidly evolve and grow out of control. Notably, functional loss of these pathways also creates a vulnerability in these cancers because mutation or loss of some DDR genes increases reliance on other DDR genes to support continued cancer cell growth. When mutation or loss of function of two DDR genes leads to cell death, the interplay between these genes is synthetic lethality. Importantly, selective targeting of specific members of the DDR pathway represents an attractive potential therapeutic approach for the treatment of cancer. Furthermore, because genes that are mutated in cancers continue to

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function normally in healthy tissues, this treatment approach can potentially reduce drug-induced toxicity while maintaining anti-cancer activity.

Development of Highly Precise Cancer Therapiesby Blocking DNA Repair, While Sparing Healthy Cells

WEE1 Inhibitors in Advanced Solid Tumors

We are advancing our clinical-stage WEE1 inhibitor, APR-1051, for patients having tumors with mutations in PPP2R1A, FBXW7 or with increased expression of Cyclin E1 (“CCNE1”), among other genetic and/or molecular signatures.

WEE1 kinase is a key regulator of multiple phases of the cell cycle, most prominently in progression from G1 to S phase and from G2 to M phase through inhibitory phosphorylation of CDK2 and CDK1, respectively. Thus, when WEE1 is inhibited, both G1-S and G2-M checkpoints are abrogated, leading to premature S-phase and M-phase entry. Notably, the replication stress caused by CCNE1 overexpression is transformed into toxic levels of DSBs and cancer cell death when WEE1 is inhibited. These findings suggest CCNE1 overexpression is a cancer-associated vulnerability that may be used to sensitize these cancers to WEE1 inhibitors.

APR-1051 Potential Differentiation and Preclinical Data

Several WEE1 inhibitors in development by other companies have been and are currently being evaluated in clinical trials. WEE1 has been proven as a clinically validated target in various clinical studies. However, competitor WEE1 inhibitors have been associated with significant grade ≥3 hematological, gastrointestinal and cardiovascular toxicities.

We have developed a highly potent and selective inhibitor of WEE1, APR-1051, that has the potential to become the best-in-class WEE1 inhibitor. We believe that APR-1051 is potentially differentiated from other WEE1 inhibitors in its: 1) molecular structure; 2) selectivity for WEE1 versus off-target inhibition of the polo-like kinase, or PLK, family of kinases; and 3) potential absence of QT prolongation at doses that significantly inhibit WEE1.

In preclinical biochemical studies, we have observed high potency of APR-1051 for inhibition of WEE1, with an IC50 of approximately 1.6 nM; however, even when tested at a very high relative concentration of 1 μM, APR-1051 did not appreciably inhibit PLK1 (17%), PLK2 (33%) or PLK3 (12%). We believe that this high selectivity for WEE1 over PLK1, PLK2 and PLK3 is an important differentiating attribute of APR-1051 versus some of the other WEE1 inhibitors in development.

Head-to-head studies of APR-1051 versus the oral WEE1 inhibitors ZN-c3 (Azenosertib, Zentalis) and AZD-1775 (Adavosertib, Astra Zeneca) have not been conducted.

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APR-1051 Does Not Substantially Off-target PLK1, PLK2 or PLK3 and Comparison to ZN-c3 1

In vitro kinase IC50 determination of APR-1051 vs. ZN-c3: APR-1051 IC50 values show >150-fold, >50-fold, and >600-fold IC50 values compared to ZN-c3 for PLK1, PLK2, and PLK3, respectively, potentially showing higher selectivity

1 AACR-NCI-EORTC Meeting, Poster B323, 2024

In addition to the potential safety issues associated with PLK1 inhibition, in an in-vitro study we showed that PLK1 inhibition reduces the expected molecular effects of WEE1 inhibitor on phos-H2AX and phos-CDK1, hence we believe that minimal PLK1 co-inhibition enables full therapeutic potential of APR-1051.

PLK1 Inhibition Reduces the Molecular Effects of WEE1 Inhibitors in Cells1

Dose range of a PLK inhibitor GSK-461364 in combination with a single dose of APR-1051 in OVCAR3 cells suggests interference with the genotoxic effects of WEE1 inhibition (pH2AX). Western blot suggests that the PLK inhibitors, GSK-461364 and BI-2536 interfere with APR- 1051’s ability to increase pH2AX

1 AACR-NCI-EORTC Meeting, Poster B323, 2024

As part of our preclinical studies with APR-1051, we conducted a CDX mouse model study using the CCNE1-amplified ovarian cancer cell line OVCAR3. In this study we injected female mice (N=7 per group) with tumor cells and waited for tumor volume to reach approximately 150 mm3 before initiating daily administration over a period of 28 days with

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vehicle administered orally or an exploratory formulation of APR-1051 administered orally at 30 mg/kg/day. In this model we observed strong tumor growth inhibition when APR-1051 was administered at 30 mg/kg/day.

APR-1051 Exhibits Strong Tumor Control in CCNE1-Overexpressing CDX Model

In addition, pre-clinical results from an ongoing translational research collaboration with renowned oncology leader MD Anderson Cancer Center support the potential of APR-1051 both as a single agent and in rational immunotherapy combinations in HPV+ head and neck squamous cell carcinoma (HNSCC). APR-1051 demonstrated robust antiproliferative single-agent effects across a broad panel of human and murine head and neck cancer cell lines, including HPV+ subtypes, with IC50 values ranging from 8.9 to 230 nM. Significant anti-tumor synergy was observed with APR-1051 in combination with anti–PD-1 therapies, as well as in combination with cisplatin in HPV+ HNSCC animal models, positioning APR-1051 as a potential candidate for combination-based clinical trials.

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APR-1051 Potentiates the Immune Response to Checkpoint Inhibitors in an HPV+ HNSCC Animal Model

APR-1051 Synergizes with Cisplatinin Another HPV+ HNSCC Animal Model

In preclinical mice studies, APR-1051 has also demonstrated potentially favorable pharmacokinetic properties as assessed by the area under the curve, or AUC, a commonly used measure of drug exposure. Head-to-head studies of APR-1051 versus the oral ZN-c3 and AZD-1775 have not been conducted; however, data for the ZN-c3 and AZD-1775 have been previously disclosed by Zentalis and suggest that APR-1051 may have potentially advantageous drug exposure.

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APR-1051 Pre-Clinical Data Highlight Potentially Favorable Pharmacokinetic Properties

In addition, QT prolongation has been reported with competitor WEE1 inhibitors developed by other companies. APR-1051 showed negligible inhibition of hERG channels, which may indicate a lower likelihood of QT prolongation at doses expected to achieve meaningful WEE1 inhibition.

APR-1051 Exhibits Substantially Lower Inhibition of hERG than of WEE11

1AACR-NCI-EORTC Meeting, Poster B323, 2024

APR-1051 Clinical Trial

In March 2024, our IND for APR-1051 (IND 169359) went into effect and in the second quarter of 2024 we enrolled the first patient into ACESOT-1051 (a Multi-Center Evaluation of WEE1 Inhibitor in Patients with Advanced Solid Tumors, APR-1051). The study is evaluating APR-1051 for monotherapy treatment of solid tumors harboring deleterious mutations in FBXW7 or PPP2R1A, overexpressing Cyclin E, colorectal cancer with KRAS GLY12 or GLY13 and TP53 co-mutation, patients with HPV+ oropharyngeal squamous cell carcinoma,or cervical, vaginal, or vulvar squamous cell carcinoma, as well as patients with uterine serous carcinoma, regardless of biomarker status. The primary objectives of this Phase 1 study are to measure safety, dose-limiting toxicities (DLTs), maximum tolerated dose or maximum administered dose (MTD/MAD), and recommended Phase 2 dose (RP2D); secondary objectives are to evaluate pharmacokinetics and preliminary efficacy according to RECIST Version 1.1 or PCWG3 criteria; exploratory objectives are to evaluate pharmacodynamic parameters. A total of 9 cohorts are planned for ACESOT-1051 that will evaluate doses of 10 mg to 300 mg once daily (higher doses are permitted if indicated). As of March 2, 2026, we are enrolling cohort 8 for ACESOT-1051 to evaluate a dose of 220 mg once daily. In addition, we intend to enroll additional patients as backfill cohorts, in order to obtain further safety, efficacy and PK data. Active enrollment is ongoing at three sites in the U.S. (NCT06260514) with additional sites planned. Up to 130 patients are planned to be enrolled in this Phase 1 study, including up to 50 patients in the dose-escalation Part 1 and up to additional 80 patients in the dose-optimization

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Part 2 of the study. We anticipate additional open-label safety/efficacy data to be available in the second quarter of 2026. We expect to complete the dose-escalation part of this study in the third quarter of 2026.

ACESOT-1051: Study Design

* Higher doses permitted if indicated

Preliminary results provide early clinical proof-of-concept of APR-1051. On January 29, 2026, we announced the first uPR observed in a patient enrolled in the ongoing Phase 1 ACESOT-1051 dose-escalation study: a patient with PPP2R1A-mutated uterine serous carcinoma, a form of endometrial cancer, treated at the 150 mg dose level of APR-1051. At the protocol-defined 8-week first imaging assessment, the patient achieved a 50% reduction in target lesion size per RECIST v1.1 criteria, along with a marked reduction in cancer antigen 125 (CA-125) levels, from 732 to 70 U/mL. CA-125 is a well-recognized tumor marker in endometrial cancer. On February 18, 2026, we announced the second uPR observed in a patient with PPP2R1A-mutated endometrial cancer, treated at the 220 mg dose level: at the first imaging assessment the patient achieved a 50% reduction in target lesion size, along with a marked decline in CA-125 from 362 at baseline to 47 U/mL, further supporting the anti-tumor activity of APR-1051.

Five more patients in ACESOT-1051 have achieved stable disease in earlier cohorts of the ACESOT-1051 study, including a 5% reduction in tumor burden at the 70 mg dose in a patient with HPV+ HNSCC and a 15% reduction in a patient with FBXW7-mutated colon cancer treated at the 100 mg dose level. Two additional patients at the 100 mg dose and another patient treated at the 150 mg dose level achieved stable disease at the first follow-up imaging assessment.

Collectively, these findings suggest that APR-1051 may have therapeutic potential across a range of solid tumors, with a potential dose-response trend.

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ACESOT-1051 Clinical Trial, Summary of Duration of Treatment (N=23)

ACESOT-1051 Clinical Trial, Safety Results

Preliminary results indicate that APR-1051 is safe and well-tolerated.

Treatment Related AEs in Patients Treated With APR-1051, as of February 18, 2026 (N=23):

We believe that the emerging clinical proof of concept responses, together with the potential dose-response trend that was observed with increasing single-agent activity across lower doses, and without class-limiting toxicity to date, support our development strategy of differentiated WEE1 inhibition through a potentially improved therapeutic index (TI), as low TI has been a major hurdle in the development of WEE1 inhibitors.

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ATR Inhibitors in Advanced Solid Tumors

Our second clinical-stage synthetic lethality product candidate is ATRN-119 (Mosipasertib), an ATR inhibitor for patients with solid tumors having defined genetic mutations in DDR-related genes.

Ataxia Telangiectasia and Rad3-related (ATR) and Checkpoint Kinase 1 (CHK1) are critical DNA damage response kinases that prevent the collapse of replication forks into DSBs. ATR is one of several key regulators of the response to defective DNA replication and DNA damage, which occurs more commonly in cancer cells than in normal cells.

In response to these cancer-associated genomic insults, ATR is activated to inhibit progression to cellular division and prevent the assembly of the SLX1-SLX4, MUS81-EME1 and XPF-ERCC1 (SMX) endonuclease (DNA cutting) complex. When ATR is inhibited, the SMX complex is inappropriately activated, promoting the cutting of replication forks into DSBs. In association with ATR’s fundamental roles in these replication responses, cells with increased oncogenic stress, p53 mutations and deficiencies in DDR pathways are predicted to have increased sensitivity to ATR inhibition. Accordingly, ATR inhibition is also predicted to sensitize cells to DNA-damaging chemotherapy, radiotherapy, and PARP inhibitor treatments, making ATR inhibitors particularly attractive for the development of novel combination therapies.

We have developed a highly potent and selective macrocyclic inhibitor of ATR, ATRN-119, the first oral macrocyclic ATR inhibitor to enter clinical trials. On October 15, 2025, we announced that we had determined the recommended Phase 2 dose (RP2D) of ATRN-119 in the ABOYA-119 Phase 1/2a dose-escalation study, in patients with advanced solid tumors.

ATRN-119 (Mosipasertib) Preclinical Data

ATRN-119 is a macrocycle and is structurally dissimilar to three oral ATR inhibitors for which chemical structures have been disclosed: AZD-6738 (AstraZeneca), BAY1895344 (Bayer), and RP-3500 (Repare). The macrocyclic structure of ATRN-119 was designed to restrict the conformational freedom of the molecule, or ability to rotate freely around certain chemical bonds, which may reduce its ability to bind off-target proteins, resulting in potentially increased tolerability, hence permitting higher efficacious drug dosing. Consistent with this hypothesis, ATRN-119 has demonstrated increased selectivity for ATR versus related members of the PIKK family of kinases, including ataxia-telangiectasia mutated (ATM), DNA-dependent protein kinase (DNA-PK) and mammalian target of rapamycin (mTOR). In preclinical studies, we have observed a high potency of ATRN-119 for inhibition of ATR, with an IC50 of approximately 4 nM, whereas the IC50 of ATRN-119 is significantly higher for off-target inhibition of ATM (>600-fold), DNA-PK (>2000-fold) and mTOR (>2000-fold). Selectivity for ATR over other kinases, including PIKKs, may potentially limit toxicity from off-target inhibition. Comprehensive in-vitro head-to-head studies of ATRN-119 versus the oral ATR inhibitors AZD-6738, BAY1895344, and RP-3500 have not been conducted, but data for these other ATR inhibitors have been reported in peer-reviewed scientific publications.

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ATRN-119 Displays High Selectivity for ATR Versus Related PIKK Kinases

ATR ATM DNA-PK mTOR

1) ATRN-119 data from HCT116 – Bcl/XL cell line

2) Foote et al (2018), J Med Chem

3) Lücking et al (2020), J Med Chem

4) Roulston et al (2022), Mol Cancer Ther

We observed ATRN-119 to have a potentially favorable tolerability profile across our preclinical studies and animal models. As part of our preclinical studies with ATRN-119, we conducted cell line-derived xenograft, or CDX, mouse model studies, using the colon cancer cell line HCT-116 (mutated KRAS, p53 null). In this study we injected female mice (N=4 per group) with tumor cells and waited for tumor volume to reach approximately 150 mm3 before initiating daily administration over a period of 17 days with vehicle administered orally; ATRN-119 administered orally at 100 mg/kg/day; ATRN-157 (an active metabolite of ATRN-119 with comparable potency and selectivity to the parent compound) was administered subcutaneously at 20 mg/kg/day; or a competitor ATR inhibitor administered orally at 25 mg/kg/day. In this study, both ATRN-119 and ATRN-157 demonstrated statistically significant tumor growth inhibition as compared to vehicle control and smaller tumor volume than measured in mice receiving the competitor ATR inhibitor. Body weight loss, as a measurement of tolerability, was negligible across all groups of mice in this study.

ATRN-119 Halts Tumor Progression and Causes No Obvious Toxicity in KRAS-Mutant, p53-Null CDX Model

Data from clinical trials testing the oral ATR inhibitors BAY1895344, ART0380 and RP-3500 have been presented and support preclinical observation of synthetic lethality between ATR inhibitors and ATM-deficient cancers. In addition, data from various clinical trials with oral ATR inhibitors demonstrated responses in patients with tumors having mutations in ARID1A, CDK12, RAD51C and BRCA1/2. We believe these data are encouraging and indicate that additional DDR-related mutations may be synthetic lethal with ATR inhibitors.

ATRN-119(Mosipasertib) Clinical Trial

In our open-label Phase 1/2a clinical trial of ATRN-119 as monotherapy, we enrolled patients with advanced solid tumors having at least one mutation in a defined panel of DDR-related genes. In the monotherapy dose escalation phase (Part 1) of our trial, the primary endpoint was evaluating the tolerability and pharmacokinetics of continuous daily oral dosing of ATRN-119 using a 3+3 trial design in up to approximately 72 patients (up to 54 patients dosed once-daily and

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up to 18 patients dosed twice-daily). A secondary endpoint was evaluating potential initial efficacy. An efficacy evaluation was performed every eight weeks. On October 15, 2025, we announced that we had determined the recommended Phase 2 dose (RP2D) of 1,100 mg once daily for ATRN-119 monotherapy. Based on the completion of dose escalation, we are considering further ATRN-119 development in combination approaches that could expand its therapeutic potential. We believe that ATRN-119's mechanism of action, favorable safety profile, and pharmacological characteristics make it an ideal candidate for combination with DNA-damaging agents, including radiation therapy, antibody-drug conjugates and with immune checkpoint inhibitors.

As part of this strategic focus, we have paused further enrollment in both once daily and twice daily monotherapy dosing arms of ABOYA-119 and started an orderly wind-down of certain clinical trial site activities associated with the monotherapy arms as we explore ATTN-119 in potential combination approaches.

Phase 1/2a Clinical Trial of ATRN-119 (Mosipasertib) as Monotherapy

In the Phase 1 dose-escalation study, ATRN-119 demonstrated:

● Dose-proportional pharmacokinetics supporting once-daily dosing

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ATRN-119 (Mosipasertib), Phase 1/2a Safety Results

Treatment Related AEs Reported in ≥ 2 Patients and/or any Grade ≥ 3 in Patients Treated With ATRN-119 QD as of February 26, 2026 (N=33):

ATRN-119 (Mosipasertib), Phase 1/2a, Summary of Duration of Treatment

A total of eight stable disease patients were observed in the dose escalation Phase 1 trial, four at the QD cohorts and 4 at the BID cohorts:

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Duration Of Treatment for Patients Dosed QD (N=33)

Opportunities for Combination of ATRN-119 (Mosipasertib) with Other Therapies

Combinations of anti-cancer agents have the potential to interact synergistically. This synergy can potentially augment efficacy over monotherapy regimens and reduce the risk of drug resistance. We believe that our ATRN-119 could potentially interact synergistically with various anti-cancer agents, including PARP inhibitors, WEE1 inhibitors, radiopharmaceuticals, chemotherapies, ADCs and immunotherapies. In a preclinical study, we evaluated ATRN-119 and the PARP inhibitor olaparib as both monotherapies and a combination therapy in a patient-derived xenograft, or PDX, ovarian cancer mouse model. Mice were first transplanted with patient-derived BRCA2 deficient ovarian cancer tumor material. When tumors grew to approximately 100 mm3 the mice were dosed (N=6-8 per group) with vehicle, olaparib at 50 mg/kg/day, ATRN-119 at 90 mg/kg twice daily, or the combination of the two agents at the same doses and schedules. In this study, ATRN-119 and olaparib monotherapies demonstrated comparable tumor growth inhibition. However, the combination of ATRN-119 + olaparib demonstrated statistically significant tumor growth inhibition compared to either single agent or vehicle control. Body weight loss, as a measurement of tolerability, was negligible in the mice receiving any of these regimens.

We are currently in discussions with leading academic centers to explore combining ATRN-119 with radiation in patients with HPV+ head and neck cancer. Additional investigator-led studies evaluating ATRN-119 in combination with an I/O agent and antibody-drug conjugates (ADCs) are also being explored.

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ATRN-119 + Olaparib Combination Drives Regression and No Serious Toxicity in BRCA2-deficient PDX Model

DYRK1A/B Inhibitor, APR-1602

We also have an early preclinical program, in which a first generation macrocyclic lead candidate was selected. We plan to have APR-1602 ready to enter IND-enabling studies during the fourth quarter of 2026.

Manufacturing

We currently contract with third parties for the manufacture of our product candidates for certain preclinical studies and clinical trial materials, including raw materials and consumables necessary for their manufacture, consistent with applicable cGMP requirements. We intend to continue to contract production of these materials and services in the future, including commercial manufacture if our product candidates receive marketing approval. We do not own or operate cGMP manufacturing facilities, nor do we currently plan to build our own cGMP manufacturing capabilities for production of our product candidates for clinical or commercial use.

Although we rely upon contract manufacturers for the manufacture of our product candidates for pre-clinical trials and clinical trials, we have personnel and consultants who oversee our contract manufacturers. In the future, we may also rely upon collaboration partners, in addition to contract manufacturers, for the manufacture of our product candidates or any products for which we obtain marketing approval.

Currently, we have agreements with manufacturers for the production of APR-1051 and ATRN-119 active pharmaceutical ingredients, or APIs, and drug products. We believe that these third parties have sufficient capacity to meet our current demand and, in the event they fail to meet our demand, we believe that adequate alternative sources for the supply of materials for our product candidates exist.

We expect that one or more of our current contract manufacturers will have capacity to support commercial scale production but we do not have any formal agreements in place at this time given our early stage of development. If needed, we believe we can identify and establish agreements with additional contract manufacturers to provide APIs as well as drug product. We intend to identify and qualify additional manufacturers to provide the APIs, drug product and other services pertaining to our clinical and potential future supply chains prior to seeking marketing approval for any of our product candidates.

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All of our product candidates are small molecules and are manufactured synthetically from readily available starting materials. The chemistry underlying our product candidates appears amenable to scale-up and does not currently require unusual equipment in the manufacturing process. We expect to continue to develop product candidates that can be produced cost-effectively at contract manufacturing facilities.

Manufacturing clinical products is subject to extensive regulations that impose various procedural and documentation requirements, which govern record keeping, manufacturing processes and controls, personnel, quality control and quality assurance. Our contract manufacturers are required to comply with current good manufacturing practice (cGMP) regulations, which are regulatory requirements for the production of pharmaceuticals for use in humans.

Competition

The pharmaceutical and biotechnology industries generally, and the cancer drug sector specifically, are highly competitive and characterized by rapidly advancing technologies, evolving understanding of disease etiology and a strong emphasis on proprietary drugs. While we believe that our product candidates, development capabilities, experience and scientific knowledge provide us with competitive advantages, we face significant potential competition from many different sources, including major pharmaceutical, specialty pharmaceutical and biotechnology companies, academic institutions, governmental agencies and public and private research institutions. Any product candidates that we successfully develop and commercialize will compete with existing therapies and new therapies that may become available in the future.

There are a large number of companies developing or marketing treatments for cancer, including the indications for which we may develop product candidates. Many of the companies that we compete against or may compete against in the future have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals and marketing approved drugs than we do. Small or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or that may be necessary for, our programs.

Our commercial opportunity could be reduced or eliminated if our competitors develop and commercialize drugs that are safer, more effective, have fewer or less severe side effects, are more convenient or are less expensive than any drugs that we may develop. Our competitors also may obtain FDA or other regulatory approval for their drugs more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market. The key competitive factors affecting the success of all of our product candidates, if approved, are likely to be their efficacy, safety, convenience and price, in guiding the use of related therapeutics, the level of generic competition and the availability of reimbursement from government and other third-party payors.

The most common methods of treating patients with cancer are surgery, radiation and therapy with drugs or biologics. There are a variety of available drug therapies marketed for cancer. In many cases, these drugs are administered in combination to enhance efficacy. Some of the currently-approved drug therapies are branded and subject to patent protection and may be established as standard of care for the treatment of indications for which we may choose to seek regulatory approvals. Many of these approved drugs are well-established therapies and are widely accepted by physicians, patients and third-party payors, and even if our drug candidates were to be approved, there can be no assurance that our drugs would displace existing treatments.

In addition to currently marketed therapies, there are also a number of drugs in late-stage clinical development to treat cancer, including for the treatment of the indications for which we are developing product candidates. These clinical-stage drug candidates may provide efficacy, safety, convenience and other benefits that are not provided by currently-marketed therapies. As a result, they may provide significant competition for any of our product candidates for which we obtain regulatory approval.

With respect to our WEE1 inhibitor product candidate, APR-1051, several companies are developing WEE1 inhibitors, including Zentalis Pharmaceuticals, Debiopharm, IMPACT Therapeutics, Schrodinger and Acrivon Therapeutics.

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Several of these companies are conducting clinical trials with their WEE1 inhibitors as monotherapy and/or in combination with other chemotherapies and targeted agents. AstraZeneca was previously developing a clinical-stage WEE1 inhibitor, AZD-1775 (Adavosertib), but reported discontinuation of further development in July 2022.

With respect to our ATR inhibitor, ATRN-119, several companies are developing ATR inhibitors, including Artios Pharma, AstraZeneca, IMPACT Therapeutics, Merck KGaA and Xeno Therapeutics (formerly Repare Therapeutics’ ATR inhibitor program). Several of these companies are conducting clinical trials with their ATR inhibitors as monotherapy and/or in combination with other chemotherapies and targeted agents.

Intellectual Property

We strive to protect the proprietary technologies that we believe are important to our business, including seeking and maintaining patent protection intended to cover claims directed to composition of matter, methods-of-use, formulations, and manufacturing processes for our product candidates, as well as other inventions that are important to our business.

Our success will depend significantly on our ability to obtain and maintain patent and other proprietary protection for commercially important technology, inventions, and know-how related to our business, defend and enforce our patents, preserve the confidentiality of our trade secrets, and operate without infringing the valid and enforceable patents and other proprietary rights of third parties.

A third party may hold intellectual property, including patent rights, which are important or necessary to the development or commercialization of our product candidates. If it becomes necessary for us to use patented or proprietary technology of third parties to develop or commercialize our product candidates, we may need to seek a license from such third parties. Our business could be harmed, possibly materially, if we are unable to obtain such a license on terms that are commercially reasonable, or at all.

We may seek to expand our intellectual property estate by filing patent applications directed to dosage forms, methods of treatment, diagnostics, and additional compounds and their derivatives. Specifically, we have sought and will continue to seek patent protection in the United States and internationally for novel compositions of matter covering the compounds of our product candidates, the chemistries and processes for manufacturing these compounds, and the use of these compounds in a variety of therapies. The chemical structure of eprenetapopt is in the public domain. Accordingly, we do not own or license any composition of matter patents claiming the compound of eprenetapopt and will not in the future own or license any composition of matter patents claiming the chemical structure of eprenetapopt as described in the public domain.

The patent positions of biopharmaceutical companies like us are generally uncertain and involve complex legal, scientific and factual questions. In addition, the coverage claimed in a patent application can be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. Consequently, we do not know whether any of our product candidates will be protectable or remain protected by enforceable patents. We cannot predict whether the patent applications we are currently pursuing will issue as patents in any particular jurisdiction or whether the claims of any issued patents will provide sufficient proprietary protection from competitors. Any patents that we hold may be challenged, circumvented or invalidated by third parties.

Because patent applications in the United States and certain other jurisdictions are maintained in secrecy for 18 months, and since publication of discoveries in the scientific or patent literature often lags actual discoveries, we cannot be certain of whether inventions covered by pending patent applications represent the first priority filings of those inventions. Moreover, we may have to participate in proceedings declared by the United States Patent and Trademark Office, or USPTO, in post-grant challenge proceedings at the USPTO or at a foreign patent office, such as inter partes review and post grant review proceedings at the USPTO and opposition proceedings at the European Patent Office, that challenge priority of invention or other features of patentability. Such proceedings could result in substantial cost, even if the eventual outcome is favorable to us. For more information regarding the risks related to our intellectual property, see “Risk Factors—Risks Related to Our Intellectual Property.”

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Patent portfolio

As of December 31, 2025, our exclusively owned patent portfolio is directed toward various aspects of our product candidates and research programs.

As of December 31, 2025, the portion of our portfolio for DDR inhibitors, including our ATR and WEE1 programs, consists of 4 issued U.S. patents, 2 U.S. patent applications, 30 pending non-U.S. patent applications (including 1 International patent application), and 22 non-U.S. patents. The claims of these owned patents and patent applications are directed toward composition of matter, pharmaceutical compositions and methods of use. The granted patents and pending applications, if issued, in this family are expected to expire between 2035 and 2045, not giving effect to any potential patent term extensions and patent term adjustments and assuming payment of all appropriate maintenance, renewal, annuity, or other governmental fees.

As of December 31, 2025, the portion of our portfolio for p53 reactivators, including eprenetapopt, consists of 3 issued U.S. patents, 1 pending U.S. application, and approximately 80 foreign issued patents. The claims of these owned patents and patent applications are directed toward drug product formulations and methods of use. The granted patents and pending applications, if issued, in this family are expected to expire between 2031 and 2040, not giving effect to any potential patent term extensions and patent term adjustments and assuming payment of all appropriate maintenance, renewal, annuity, or other governmental fees.

Intellectual property protection

The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the earliest date of filing a non-provisional patent application.

In the United States, the Hatch-Waxman Act permits a patent holder to apply for patent term extension of a patent that covers an FDA-approved drug, which, if granted, can extend the patent term of such patent to compensate for part of the patent term lost during the FDA regulatory review process. This extension can be for up to five years beyond the original expiration date of the patent. The length of the patent term extension is related to the length of time the drug is under regulatory review. Patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval, only one patent applicable to an approved drug may be extended and only those claims covering the approved drug, a method for using it, or a method for manufacturing it may be extended.

Similar provisions are available in Europe and other non-United States jurisdictions to extend the term of a patent that covers an approved drug. In the future, if and when our product candidates receive FDA approval, we expect to apply for patent term extensions on patents covering those product candidates. While we intend to seek patent term extensions to any of our patents in any jurisdiction where such extensions are available, there is no guarantee that the applicable authorities, including the FDA and the USPTO in the United States, will agree with our assessment of whether such extensions should be granted, and even if granted, the length of such extensions.

In addition to our reliance on patent protection for our inventions, product candidates and research programs, we also rely on trade secrets and confidentiality agreements to protect our technology, know-how and other aspects our business that are not amenable to, or that we do not consider appropriate for, patent protection. Although we take steps to protect our proprietary information and trade secrets, including through contractual means with our employees and consultants, third parties may independently develop substantially equivalent proprietary information and techniques or otherwise gain access to our trade secrets or disclose our technology. Thus, we may not be able to meaningfully protect our trade secrets. It is our policy to require our employees, consultants, outside scientific collaborators, sponsored researchers and other advisors to execute confidentiality agreements upon the commencement of employment or consulting relationships with us. These agreements provide that all confidential information concerning our business or financial affairs developed or made known to the individual or entity during the course of the party’s relationship with us is to be kept confidential and not disclosed to third parties except in specific circumstances. In the case of employees, the agreements provide that all inventions conceived by the individual, and which are related to our current or planned business or research and development or made during normal working hours, on our premises or using our equipment or proprietary

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information, are our exclusive property. However, such confidentiality agreements and invention assignment agreements can be breached and we may not have adequate remedies for any such breach. For more information regarding the risks related to our intellectual property, see “Risk Factors—Risks Related to Our Intellectual Property.”

Government Regulation

Government regulation and product approvals

Government authorities in the United States, at the federal, state and local level, and in other countries and jurisdictions, including the 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 drug products. The processes for obtaining marketing approvals in the United States and in foreign countries and jurisdictions, along with subsequent compliance with applicable statutes and regulations and other regulatory authorities, require the expenditure of substantial time and financial resources.

Review and approval of drugs in the United States

In the United States, the FDA approves drug products under the Federal Food, Drug, and Cosmetic Act, or FDCA, and implementing regulations. The failure to comply with applicable requirements under the FDCA and other applicable laws at any time during the product development process, approval process or after approval may subject an applicant and/or sponsor to a variety of administrative or judicial sanctions, including refusal by the FDA to approve pending applications, withdrawal of an approval, debarment, imposition of a clinical hold, issuance of warning letters and other types of letters, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement of profits, or civil or criminal investigations and penalties brought by the FDA and the Department of Justice or other governmental entities.

An applicant seeking approval to market and distribute a new drug product in the United States must typically undertake the following:

● review by an FDA advisory committee, where appropriate or if applicable;

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● payment of user fees and securing FDA approval of the NDA; and

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 candidate or disease. A clinical hold may occur at any time during the life of an IND and may affect one or more specific trials or all trials conducted under the IND. The testing and approval process requires substantial time, effort, and financial resources.

Preclinical studies

Before an applicant begins testing a compound with potential therapeutic value in humans, the drug candidate enters the preclinical testing stage. Preclinical studies include laboratory evaluation of product chemistry, toxicity and formulation, as well as in vitro and animal studies to assess the potential safety and activity of the drug for initial testing in humans and to establish a rationale for therapeutic use. The conduct of preclinical studies is subject to federal regulations and requirements, including GLP regulations. The results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and plans for clinical trials, among other things, are submitted to the FDA as part of an IND. Some long-term preclinical testing, such as animal tests of reproductive AEs and carcinogenicity, may continue after the IND is submitted.

The IND and IRB processes

An IND is an exemption from the FDCA that allows an unapproved drug to be shipped in interstate commerce for use in an investigational clinical trial and a request for FDA authorization to administer an investigational drug to humans. Such authorization must be secured prior to interstate shipment and administration of any new drug that is not the subject of an approved NDA. In support of a request for an IND, a sponsor must submit, among other things, a protocol for each clinical trial and any subsequent protocol amendments must be submitted to the FDA as part of the IND. The sponsor may be a company seeking to develop the drug or, as in the case of an investigator-initiated trial, the sponsor may be an investigator who is conducting the trial. In addition, the results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and plans for clinical trials, among other things, are submitted to the FDA as part of an IND. The FDA requires a 30-day waiting period after the filing of each IND before clinical trials may begin. This waiting period is designed to allow the FDA to review the IND to determine whether human research subjects will be exposed to unreasonable health risks. At any time during this 30-day period, the FDA may raise concerns or questions about the conduct of the trials as outlined in the IND and impose a clinical hold. In this case, the IND sponsor and the FDA must resolve any outstanding concerns before clinical trials can begin. If the FDA has neither commented on nor questioned the IND within this 30-day period, the IND is deemed to be in effect and the clinical trial proposed in the IND may begin.

Following commencement of a clinical trial under an IND, the FDA may also place a clinical hold or partial clinical hold on that trial. A clinical hold is an order issued by the FDA to the sponsor to delay a proposed clinical investigation or to suspend an ongoing investigation. A partial clinical hold is a delay or suspension of only part of the clinical work requested under the IND. For example, a specific protocol or part of a protocol is not allowed to proceed, while other protocols may do so. No more than 30 days after imposition of a clinical hold or partial clinical hold, the FDA will provide the sponsor a written explanation of the basis for the hold. Following issuance of a clinical hold or partial clinical hold, an investigation may only resume after the FDA has notified the sponsor that the investigation may proceed. The FDA will base that determination on information provided by the sponsor correcting the deficiencies previously cited or otherwise satisfying the FDA that the investigation can proceed.

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A sponsor may choose, but is not required, to conduct a foreign clinical study under an IND. When a foreign clinical study is conducted under an IND, all IND requirements must be met unless waived. When the foreign clinical study is not conducted under an IND, the sponsor must ensure that the study complies with certain FDA regulatory requirements in order to use the study as support for an IND or application for marketing approval. Specifically, FDA has promulgated regulations governing the acceptance of foreign clinical trials not conducted under an IND, establishing that such studies will be accepted as support for an IND or application for marketing approval if the study was conducted in accordance with GCP, including review and approval by an independent ethics committee, or IEC, and use of proper procedures for obtaining informed consent from subjects, and the FDA is able to validate the data from the study through an on-site inspection if FDA deems such inspection necessary. The GCP requirements encompass both ethical and data integrity standards for clinical studies. The FDA’s regulations are intended to help ensure the protection of human subjects enrolled in non-IND foreign clinical trials, as well as the quality and integrity of the resulting data. They further help ensure that non-IND foreign studies are conducted in a manner comparable to that required for IND studies. If a marketing application is based solely on foreign clinical data, the FDA requires that the foreign data be applicable to the U.S. population and U.S. medical practice; the studies must have been performed by clinical investigators of recognized competence; and the FDA must be able to validate the data through an on-site inspection or other appropriate means, if the FDA deems such an inspection to be necessary.

In addition to the foregoing IND requirements, an IRB representing each institution participating in the clinical trial must review and approve the plan for any clinical trial before it commences at that institution, and the IRB must conduct continuing review and reapprove the study at least annually. The IRB must review and approve, among other things, the study protocol and informed consent information to be provided to study subjects. An IRB must operate in compliance with FDA regulations. An IRB can suspend or terminate approval of a clinical trial at its institution, or an institution it represents, if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the product candidate has been associated with unexpected serious harm to patients. A separate submission to the existing IND must be made for each successive clinical trial conducted during product development, as well as amendments to previously submitted clinical trials. Further, an independent IRB for each institution participating in the clinical trial must review and approve the plan for any clinical trial, its informed consent form, and other communications to study subjects before the clinical trial commences at that site. The IRB must continue to oversee the clinical trial while it is being conducted, including any changes to the study plans.

Additionally, some trials are overseen by an independent group of qualified experts organized by the trial sponsor, known as a data safety monitoring board or committee. This group provides authorization for whether or not a trial may move forward at designated check points based on access that only the group maintains to available data from the study. Suspension or termination of development during any phase of clinical trials can occur if it is determined that the participants or patients are being exposed to an unacceptable health risk. Other reasons for suspension or termination may be made by us based on evolving business objectives and/or competitive climate.

Information about certain clinical trials must be submitted within specific timeframes to the National Institutes of Health, or NIH, for public dissemination on its ClinicalTrials.gov website.

Human clinical trials in support of an NDA

Clinical trials involve the administration of the investigational product to human subjects under the supervision of qualified investigators in accordance with GCP requirements, which include, among other things, the requirement that all research subjects provide their informed consent in writing before their participation in any clinical trial. Clinical trials are conducted under written study protocols detailing, among other things, the inclusion and exclusion criteria, the objectives of the study, the parameters to be used in monitoring safety and the effectiveness criteria to be evaluated.

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Human clinical trials are typically conducted in the following sequential phases, which may overlap or be combined:

Progress reports detailing the results of the clinical trials must be submitted at least annually to the FDA and more frequently if serious AEs occur. In addition, IND safety reports must be submitted to the FDA for any of the following: serious and unexpected suspected adverse reactions for which there is evidence to suggest a causal relationship between the drug and the AE; findings from other studies or animal or in vitro testing that suggest a significant risk in humans exposed to the drug; and any clinically important increase in the case of a serious suspected adverse reaction over that listed in the protocol or investigator brochure. Phase 1, Phase 2 and Phase 3 clinical trials may not be completed successfully within any specified period, or at all. Furthermore, the FDA or the sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution, or an institution it represents, if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the drug has been associated with unexpected serious harm to patients. The FDA will typically inspect one or more clinical sites to assure compliance with GCP and the integrity of the clinical data submitted.

Regulatory authorities, an IRB or the sponsor may suspend or discontinue a clinical trial at any time on various grounds, including a finding that the subjects are being exposed to an unacceptable health risk, the clinical trial is not being conducted in accordance with the FDA’s or the IRB’s requirements, or if the drug has been associated with unexpected serious harm to subjects. Some studies also include a data safety monitoring board, which receives special access to unblinded data during the clinical trial and may advise the sponsor to halt the clinical trial if it determines that there is an unacceptable safety risk for subjects or other grounds, such as no demonstration of efficacy.

Concurrent with clinical trials, companies often complete additional animal studies and must also develop additional information about the chemistry and physical characteristics of the drug as well as finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing quality batches of the drug candidate and, among other things, must develop methods for testing the identity, strength, quality, and purity of the final drug. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that the drug candidate does not undergo unacceptable deterioration over its shelf life.

Submission of an NDA to the FDA

Assuming successful completion of required clinical testing and other requirements, the results of the preclinical studies and clinical trials, together with detailed information relating to the product’s chemistry, manufacture, controls and

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proposed labeling, among other things, are submitted to the FDA as part of an NDA requesting approval to market the drug product for one or more indications. Data can come from company-sponsored clinical trials intended to test the safety and effectiveness of a use of a product, or from several alternative sources, including investigator-initiated trials that are not sponsored by company. Under federal law, the submission of NDAs requiring clinical data is additionally subject to an application user fee, which for federal fiscal year 2025 is $4,310,002. The sponsor of an approved NDA is also subject to annual program fees, which for fiscal year 2025 are $403,889 per eligible product.

The FDA conducts a preliminary review of an NDA within 60 days of its receipt and informs the sponsor whether the application is sufficiently complete to permit substantive review. The FDA may request additional information rather than accept an NDA for filing. In this event, the application must be resubmitted with the additional information. The resubmitted application is also subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins an in-depth substantive review. The FDA has agreed to specified performance goals in the review process of NDAs. Most such applications are meant to be reviewed within ten months from the filing date, and most applications for “priority review” products are meant to be reviewed within six months of the filing date. The review process and the Prescription Drug User Fee Act goal date may be extended by the FDA for three additional months to consider new information or clarification provided by the applicant to address an outstanding deficiency identified by the FDA following the original submission.

Before approving an NDA, the FDA typically will inspect the facility or facilities where the product is or will be manufactured. These pre-approval inspections may cover all facilities associated with an NDA submission, including drug component manufacturing (such as APIs), finished drug product manufacturing, and control testing laboratories. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. Additionally, before approving an NDA, the FDA will typically inspect one or more clinical sites to assure compliance with GCP.

In addition, as a condition of approval, the FDA may require an applicant to develop a REMS. REMS use risk minimization strategies beyond the professional labeling to ensure that the benefits of the product outweigh the potential risks. To determine whether a REMS is needed, the FDA will consider the size of the population likely to use the product, seriousness of the disease, expected benefit of the product, expected duration of treatment, seriousness of known or potential AEs, and whether the product is a new molecular entity. REMS can include medication guides, physician communication plans for healthcare professionals, and elements to assure safe use, or ETASU. ETASU may 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 FDA may require a REMS before approval or post-approval if it becomes aware of a serious risk associated with use of the product. The requirement for a REMS can materially affect the potential market and profitability of a product.

The FDA is required to refer an application for a novel drug to an advisory committee or explain why such referral was not made. Typically, an advisory committee is a panel of independent experts, including clinicians and other scientific experts, that reviews, evaluates and provides a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions. In September 2025, FDA announced that it is considering ending advisory committee on new drugs because they take up significant resources and may not be needed. It is currently unclear whether and to what extent FDA may implement such changes in its use of advisory committees.

Fast track, breakthrough therapy and priority review designations

The FDA is authorized to designate certain products for expedited review if they are intended to address an unmet medical need in the treatment of a serious or life-threatening disease or condition. These programs are referred to as fast track designation, breakthrough therapy designation and priority review designation. In May 2014, the FDA published a final Guidance for Industry titled “Expedited Programs for Serious Conditions-Drugs and Biologics,” which provides guidance on the FDA programs that are intended to facilitate and expedite development and review of new product candidates as well as threshold criteria generally applicable to concluding that a product candidate is a candidate for these expedited development and review programs.

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Specifically, the FDA may designate a product for Fast Track review if it is intended, whether alone or in combination with one or more other products, for the treatment of a serious or life-threatening disease or condition, and it demonstrates the potential to address unmet medical needs for such a disease or condition. For Fast Track products, sponsors may have greater interactions with the FDA and the FDA may initiate review of sections of a Fast Track product’s application before the application is complete. This rolling review may be available if the FDA determines, after preliminary evaluation of clinical data submitted by the sponsor, that a Fast Track product may be effective. The sponsor must also provide, and the FDA must approve, a schedule for the submission of the remaining information and the sponsor must pay applicable user fees. However, the FDA’s time period goal for reviewing a Fast Track application does not begin until the last section of the application is submitted. In addition, the Fast Track designation may be withdrawn by the FDA if the FDA believes that the designation is no longer supported by data emerging in the clinical trial process.

Second, a product may be designated as a Breakthrough Therapy if it is intended, either alone or in combination with one or more other products, to treat a serious or life-threatening disease or condition and preliminary clinical evidence indicates that the product may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. The FDA may take certain actions with respect to Breakthrough Therapies, including holding meetings with the sponsor throughout the development process; providing timely advice to the product sponsor regarding development and approval; involving more senior staff in the review process; assigning a cross-disciplinary project lead for the review team; and taking other steps to design the clinical trials in an efficient manner.

Third, the FDA may designate a product for priority review if it is a product that treats a serious condition and, if approved, would provide a significant improvement in safety or effectiveness. The FDA determines, on a case-by-case basis, whether the proposed product represents a significant improvement when compared with other available therapies. Significant improvement may be illustrated by evidence of increased effectiveness in the treatment of a condition, elimination or substantial reduction of a treatment-limiting product reaction, documented enhancement of patient compliance that may lead to improvement in serious outcomes, and evidence of safety and effectiveness in a new subpopulation. A priority designation is intended to direct overall attention and resources to the evaluation of such applications, and to shorten the FDA’s goal for taking action on a marketing application from ten months to six months.

Accelerated approval pathway

The FDA may grant accelerated approval to a drug for a serious or life-threatening condition that provides meaningful therapeutic advantage to patients over existing treatments based upon a determination that the drug has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit. The FDA may also grant accelerated approval for such a condition when the product has an effect on an intermediate clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality, or IMM, and that is reasonably likely to predict an effect on irreversible morbidity or mortality or other clinical benefit, taking into account the severity, rarity or prevalence of the condition and the availability or lack of alternative treatments. Drugs granted accelerated approval must meet the same statutory standards for safety and effectiveness as those granted traditional approval.

For the purposes of accelerated approval, a surrogate endpoint is a marker, such as a laboratory measurement, radiographic image, physical sign or other measure that is thought to predict clinical benefit, but is not itself a measure of clinical benefit. Surrogate endpoints can often be measured more easily or more rapidly than clinical endpoints. An intermediate clinical endpoint is a measurement of a therapeutic effect that is considered reasonably likely to predict the clinical benefit of a drug, such as an effect on IMM. The FDA has limited experience with accelerated approvals based on intermediate clinical endpoints, but has indicated that such endpoints generally may support accelerated approval where the therapeutic effect measured by the endpoint is not itself a clinical benefit and basis for traditional approval, if there is a basis for concluding that the therapeutic effect is reasonably likely to predict the ultimate clinical benefit of a drug.

The accelerated approval pathway is most often used in settings in which the course of a disease is long and an extended period of time is required to measure the intended clinical benefit of a drug, even if the effect on the surrogate or intermediate clinical endpoint occurs rapidly. Thus, accelerated approval has been used extensively in the development

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and approval of drugs for treatment of a variety of cancers in which the goal of therapy is generally to improve survival or decrease morbidity and the duration of the typical disease course requires lengthy and sometimes large trials to demonstrate a clinical or survival benefit.

The accelerated approval pathway is contingent on a sponsor’s agreement to conduct, in a diligent manner, additional post-approval confirmatory studies to verify and describe the drug’s clinical benefit. As a result, a drug candidate approved on this basis is subject to rigorous post-marketing compliance requirements, including the completion of Phase 4 or post-approval clinical trials to confirm the effect on the clinical endpoint. Failure to conduct required post-approval studies, or confirm a clinical benefit during post-marketing studies, would allow the FDA to withdraw the drug from the market on an expedited basis. All promotional materials for drug candidates approved under accelerated regulations are subject to prior review by the FDA.

Even if a product qualifies for one or more of these programs, the FDA may later decide that the product no longer meets the conditions for qualification or decide that the time period for FDA review or approval will not be shortened. In addition, the manufacturer of an investigational drug for a serious or life-threatening disease is required to make available, such as by posting on its website, its policy on responding to requests for expanded access. Furthermore, fast track designation, breakthrough therapy designation, accelerated approval and priority review do not change the standards for approval and may not ultimately expedite the development or approval process.

The FDA’s decision on an NDA

The FDA reviews applications to determine, among other things, whether a product is safe and effective for its intended use and whether the manufacturing controls are adequate to assure and preserve the product’s identity, strength, quality and purity. Before approving an NDA, the FDA will inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities, including contract manufacturers and subcontracts, are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. Additionally, before approving an NDA, the FDA will typically inspect one or more clinical trial sites to assure compliance with GCPs.

Once the FDA receives an application, it has 60 days to review the NDA to determine if it is substantially complete to permit a substantive review, before it accepts the application for filing. Once the submission is accepted for filing, the FDA begins an in-depth review of the NDA. Under the goals and policies agreed to by the FDA under Prescription Drug User Fee Act, or PDUFA, the FDA has set the review goal of 10 months from the 60-day filing date to complete its initial review of a standard NDA for a new molecular entity, or NME, and make a decision on the application. For priority review applications, the FDA has set the review goal of reviewing NME NDAs within six months of the 60-day filing date. Such deadlines are referred to as the PDUFA date. The PDUFA date is only a goal and the FDA does not always meet its PDUFA dates. The review process and the PDUFA date may also be extended if the FDA requests or the NDA sponsor otherwise provides additional information or clarification regarding the submission during the review period that amends the original application.

On the basis of the FDA’s evaluation of the NDA and accompanying information, including the results of the inspection of the manufacturing facilities, the FDA may issue an approval letter or a complete response letter. An approval letter authorizes commercial marketing of the product with specific prescribing information for specific indications. 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 will issue an approval letter. The FDA has committed to reviewing such resubmissions in two or six months depending on the type of information included. Even with submission of this additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval.

If the FDA approves a product, it may limit the approved indications for use for the product, require that contraindications, warnings or precautions be included in the product labeling, require that post-approval studies, including Phase 4 clinical trials, be conducted to further assess the drug’s safety after approval, require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution

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restrictions or other risk management mechanisms, including REMS, which can materially affect the potential market and profitability of the product. The FDA may prevent or limit further marketing of a product based on the results of post-market studies or surveillance programs. After approval, many types of changes to the approved product, such as adding new indications, manufacturing changes and additional labeling claims, are subject to further testing requirements and FDA review and approval.

In addition, under the Pediatric Research Equity Act, an NDA or supplement to an NDA for a new active ingredient, indication, dosage form, dosage regimen or route of administration must contain data that are adequate to assess the safety and efficacy of the drug for the claimed indications in all relevant pediatric subpopulations, and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults or full or partial waivers from the pediatric data requirements.

Post-approval requirements

Drugs manufactured or distributed pursuant to FDA approvals are subject to pervasive and continuing regulation by the FDA, including, among other things, requirements relating to recordkeeping, periodic reporting, product sampling and distribution, advertising and promotion and reporting of adverse experiences with the product. After approval, most changes to the approved product, such as adding new indications or other labeling claims, are subject to prior FDA review and approval. There also are continuing, annual user fee requirements for any marketed products and the establishments at which such products are manufactured, as well as new application fees for supplemental applications with clinical data.

In addition, drug manufacturers and other entities involved in the manufacture and distribution of approved drugs are required to register their establishments with the FDA and state agencies, and are subject to periodic unannounced inspections by the FDA and these state agencies for compliance with cGMP requirements. Changes to the manufacturing process are strictly regulated and often require prior FDA approval before being implemented. FDA regulations also require investigation and correction of any deviations from cGMP and impose reporting and documentation requirements upon the sponsor and any third-party manufacturers that the NDA holder may decide to use. Accordingly, manufacturers must continue to expend time, money, and effort in the area of production and quality control to maintain cGMP compliance.

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including AEs of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program. Other potential consequences include, among other things:

● fines, warning or untitled letters or holds on post-approval clinical trials;

● injunctions or the imposition of civil or criminal penalties.

The FDA strictly regulates marketing, labeling, advertising and promotion of products that are placed on the market. Drugs may be promoted only for the approved indications and in a manner and for uses consistent with the approved

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labeling. 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.

In addition, the distribution of prescription drug products is subject to the Prescription Drug Marketing Act, or PDMA, which regulates the distribution of drugs and drug samples at the federal level, and sets minimum standards for the registration and regulation of drug distributors by the states. Both the PDMA and state laws limit the distribution of prescription drug product samples and impose requirements to ensure accountability in distribution.

Failure to comply with any of the FDA’s requirements could result in significant adverse enforcement actions. These include a variety of administrative or judicial sanctions, such as refusal to approve pending applications, license suspension or revocation, withdrawal of an approval, imposition of a clinical hold or termination of clinical trials, warning letters, untitled letters, modification of promotional materials or labeling, product recalls, product seizures or detentions, refusal to allow imports or exports, total or partial suspension of production or distribution, debarment, injunctions, fines, consent decrees, corporate integrity agreements, refusals of government contracts and new orders under existing contracts, exclusion from participation in federal and state healthcare programs, restitution, disgorgement or civil or criminal penalties, including fines and imprisonment. It is also possible that failure to comply with the FDA’s requirements relating to the promotion of prescription drugs may lead to investigations alleging violations of federal and state healthcare fraud and abuse and other laws, as well as state consumer protection laws. Any of these sanctions could result in adverse publicity, among other adverse consequences.

U.S. Marketing Exclusivity

In 1984, with passage of the Hatch-Waxman Amendments to the FDCA, Congress established an abbreviated regulatory scheme allowing the FDA to approve generic drugs that are shown to contain the same active ingredients as, and to be bioequivalent to, drugs previously approved by the FDA pursuant to NDAs. To obtain approval of a generic drug, an applicant must submit an abbreviated new drug application, or ANDA, to the agency. An ANDA is a comprehensive submission that contains, among other things, data and information pertaining to the API, bioequivalence, drug product formulation, specifications and stability of the generic drug, as well as analytical methods, manufacturing process validation data and quality control procedures. ANDAs are “abbreviated” because they generally do not include preclinical and clinical data to demonstrate safety and effectiveness. Instead, in support of such applications, a generic manufacturer may rely on the preclinical and clinical testing previously conducted for a drug product previously approved under an NDA, known as the reference-listed drug, or RLD.

Specifically, in order for an ANDA to be approved, the FDA must find that the generic version is identical to the RLD with respect to the active ingredients, the route of administration, the dosage form, and the strength of the drug. An applicant may submit an ANDA suitability petition to request the FDA’s prior permission to submit an abbreviated application for a drug that differs from the RLD in route of administration, dosage form, or strength, or for a drug that has one different active ingredient in a fixed-combination drug product (i.e., a drug product with multiple active ingredients). At the same time, the FDA must also determine that the generic drug is “bioequivalent” to the innovator drug. Under the statute, a generic drug is bioequivalent to a RLD if “the rate and extent of absorption of the drug do not show a significant difference from the rate and extent of absorption of the listed drug.” Upon approval of an ANDA, the FDA indicates whether the generic product is “therapeutically equivalent” to the RLD in its publication “Approved Drug Products with Therapeutic Equivalence Evaluations,” also referred to as the “Orange Book.” Physicians and pharmacists may consider a therapeutic equivalent generic drug to be fully substitutable for the RLD. In addition, by operation of certain state laws and numerous health insurance programs, the FDA’s designation of therapeutic equivalence often results in substitution of the generic drug without the knowledge or consent of either the prescribing physician or patient.

Under the Hatch-Waxman Amendments, the FDA may not approve an ANDA until any applicable period of non-patent exclusivity for the RLD has expired. The FDCA provides a period of five years of non-patent data exclusivity for a new drug containing a new chemical entity. For the purposes of this provision, an NCE is a drug that contains no active moiety that has previously been approved by the FDA in any other NDA. An active moiety is the molecule or ion responsible for the physiological or pharmacological action of the drug substance. In cases where such NCE exclusivity has been granted, an ANDA may not be submitted to the FDA until the expiration of five years from the date the NDA is approved, unless the submission is accompanied by a Paragraph IV certification that a listed patent for the RLD is

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invalid or will not be infringed by the drug that is the subject of the ANDA, in which case the applicant may submit its application four years following the original product approval.

The FDCA also provides for a period of three years of exclusivity if the NDA includes reports of one or more new clinical investigations, other than bioavailability or bioequivalence studies, that were conducted by or for the applicant and are essential to the approval of the application. This three-year exclusivity period often protects changes to a previously approved drug product, such as a new dosage form, route of administration, combination or indication. Three-year exclusivity would only be available for a drug product that contains a previously approved active moiety, provided the statutory requirement for a new clinical investigation is satisfied. Unlike five-year NCE exclusivity, an award of three-year exclusivity does not block the FDA from accepting ANDAs seeking approval for generic versions of the drug as of the date of approval of the original drug product; it does, however, block the FDA from approving ANDAs during the period of exclusivity. The FDA typically makes decisions about awards of data exclusivity shortly before a product is approved.

505(b)(2) NDAs

As an alternative path to FDA approval for modifications to formulations or uses of products previously approved by the FDA pursuant to an NDA, an applicant may submit an NDA under Section 505(b)(2) of the FDCA. Section 505(b)(2) was enacted as part of the Hatch-Waxman Amendments and permits the filing of an NDA where at least some of the information required for approval comes from studies not conducted by, or for, the applicant, and for which the applicant has not obtained a right of reference. If the 505(b)(2) applicant can establish that reliance on FDA’s previous findings of safety and effectiveness is scientifically and legally appropriate, it may eliminate the need to conduct certain preclinical studies or clinical trials of the new product. The FDA may also require companies to perform additional bridging studies or measurements, including clinical trials, to support the change from the previously approved reference drug. The FDA may then approve the new product candidate for all, or some, of the label indications for which the reference drug has been approved, as well as for any new indication sought by the 505(b)(2) applicant. An RLD’s unexpired non-patent exclusivities would also block FDA from accepting or approving 505(b)(2) NDAs in the same way as they apply to ANDAs.

Hatch-Waxman patent certification and the 30-Month Stay

Upon approval of an NDA or a supplement thereto, NDA sponsors are required to list with the FDA each patent with claims that cover the applicant’s product or an approved method of using the product. Each of the patents listed by the NDA sponsor is published in the Orange Book. When an ANDA applicant files its application with the FDA, the applicant is required to certify to the FDA concerning any patents listed for the reference product in the Orange Book, except for patents covering methods-of-use for which the ANDA applicant is not seeking approval. To the extent that the Section 505(b)(2) applicant is relying on studies conducted for an already approved product, the applicant is required to certify to the FDA concerning any patents listed for the approved product in the Orange Book to the same extent that an ANDA applicant would.

Specifically, the applicant must certify with respect to each patent that:

● the required patent information has not been filed;

● the listed patent has expired;

A certification that the new product will not infringe the already approved product’s listed patents or that such patents are invalid or unenforceable is called a Paragraph IV certification. If the applicant does not challenge the listed patents or indicates that it is not seeking approval of a patented method of use, the application will not be approved until all the

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listed patents claiming the referenced product have expired (other than method of use patents involving indications for which the applicant is not seeking approval).

If the ANDA or 505(b)(2) applicant has provided a Paragraph IV certification to the FDA, the applicant must also send notice of the Paragraph IV certification to the NDA and patent holders once the ANDA or 505(b)(2) application has been accepted for filing by the FDA. The NDA and patent holders may then initiate a patent infringement lawsuit in response to the notice of the Paragraph IV certification. The filing of a patent infringement lawsuit within 45 days after the receipt of a Paragraph IV certification automatically prevents the FDA from granting final approval of the application until the earlier of 30 months after the receipt of the Paragraph IV notice, expiration of the patent, or a decision in the infringement case that is favorable to the applicant. The ANDA or 505(b)(2) application also will not be approved until any applicable non-patent exclusivity listed in the Orange Book for the branded reference drug has expired.

Pediatric studies and exclusivity

Under the Pediatric Research Equity Act of 2003, an NDA or supplement thereto must contain data that are adequate to assess the safety and effectiveness of the drug product for the claimed indications in all relevant pediatric subpopulations, and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. With enactment of the Food and Drug Administration Safety and Innovation Act of 2012, sponsors must also submit pediatric study plans prior to the assessment data.

Those plans must contain an outline of the proposed pediatric study or studies the applicant plans to conduct, including study objectives and design, any deferral or waiver requests, and other information required by regulation. The applicant, the FDA, and the FDA’s internal review committee must then review the information submitted, consult with each other, and agree upon a final plan. The FDA or the applicant may request an amendment to the plan at any time.

The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults, or full or partial waivers from the pediatric data requirements. Additional requirements and procedures relating to deferral requests and requests for extension of deferrals are contained in FDASIA. Unless otherwise required by regulation, the pediatric data requirements do not apply to products with orphan designation.

Pediatric exclusivity is another type of non-patent marketing exclusivity in the United States and, if granted, provides for the attachment of an additional six months of marketing protection to the term of any existing regulatory exclusivity, including the non-patent and orphan exclusivity. This six-month exclusivity may be granted if an NDA sponsor submits pediatric data that fairly respond to a written request from the FDA for such data. The data do not need to show the product to be effective in the pediatric population studied; rather, if the clinical trial is deemed to fairly respond to the FDA’s request, the additional protection is granted. If reports of requested pediatric studies are submitted to and accepted by the FDA within the statutory time limits, whatever statutory or regulatory periods of exclusivity or patent protection cover the product are extended by six months. This is not a patent term extension, but it effectively extends the regulatory period during which the FDA cannot approve another application. FDA may only grant pediatric exclusivity if existing patent or exclusivity protections for the drug would otherwise expire at least 9 months after the grant of the pediatric exclusivity; FDA has 180 days to make a pediatric exclusivity determination once the NDA sponsor submits study reports required under the written request.

Orphan drug designation and exclusivity

Under the Orphan Drug Act, the FDA may designate a drug product as an “orphan drug” if it is intended to treat a rare disease or condition (generally meaning that it affects fewer than 200,000 individuals in the United States, or more in cases in which there is no reasonable expectation that the cost of developing and making a drug product available in the United States for treatment of the disease or condition will be recovered from sales of the product). A company must request orphan product designation before submitting an NDA. If the request is granted, the FDA will disclose the identity of the therapeutic agent and its potential use. Orphan product designation does not convey any advantage in or shorten the duration of the regulatory review and approval process. Among the other benefits of orphan drug designation

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are tax credits for certain research and an exemption from the NDA or BLA application fee. The FDA may revoke orphan drug designation, and if it does, it will publicize that the drug is no longer designated as an orphan drug.

If the sponsor of a product with orphan designation receives the first FDA approval for that drug for the disease or condition for which it has such designation or for a select indication or use within the rare disease or condition for which it was designated, the product generally will receive orphan product exclusivity. Orphan product exclusivity means that the FDA may not approve any other applications for the same product for the same indication for seven years, except in certain limited circumstances. If a drug or drug product designated as an orphan product ultimately receives marketing approval for an indication broader than what was designated in its orphan product application, it may not be entitled to exclusivity. Orphan drug exclusivity, however, could also block the approval of one of our therapeutic candidates for seven years if a competitor obtains orphan drug designation and FDA approval of the same therapeutic candidate for the same condition or disease as our orphan-designated drug.

Orphan exclusivity will not bar approval of another product under certain circumstances, including if a subsequent product with the same active ingredient for the same indication is shown to be clinically superior to the approved product on the basis of greater efficacy or safety, or providing a major contribution to patient care, or if the company with orphan drug exclusivity is not able to meet market demand. Further, the FDA may approve more than one product for the same orphan indication or disease as long as the products contain different active ingredients. Moreover, competitors may receive approval of different products for the indication for which the orphan product has exclusivity or obtain approval for the same product but for a different indication for which the orphan product has exclusivity.

In addition, as the FDA has interpreted the Orphan Drug Act, even if a previously approved same drug does not have unexpired orphan exclusivity, a demonstration of clinical superiority is required for a subsequent marketing application for the same orphan-designated drug for the same disease or condition to be awarded a 7-year period of orphan exclusivity upon marketing approval. In recent years, there have been multiple legal challenges to this FDA interpretation, and in August 2017, Congress amended the orphan drug provisions of the FDCA through enactment of the FDA Reauthorization Act of 2017 to codify FDA’s longstanding interpretation. Section 527 of the FDCA now expressly provides that if a sponsor of an orphan-designated drug that is otherwise the same as an already approved drug for the same rare disease or condition is seeking orphan exclusivity, FDA shall require such sponsor, to demonstrate that such drug is clinically superior to any already approved or licensed drug that is the same drug in order to obtain orphan drug exclusivity.

In September 2021, the United States Court of Appeals for the Eleventh Circuit decided in Catalyst Pharmaceuticals, Inc. v. FDA that the FDA’s interpretation of orphan drug exclusivity “for the same drug for the same disease or condition” as meaning the same “use or indication” was inappropriately narrow. This decision had the potential to significantly broaden the scope of orphan drug exclusivity for drugs that receive marketing approval for orphan indications that are narrower than their orphan-designated conditions in the United States. On January 24, 2023, the FDA issued a statement to address the uncertainty created by the circuit court’s decision in Catalyst. This notification announced that, at this time, in matters beyond the scope of that court order (i.e., ordering the FDA to set aside its approval of the specific drug at issue), the FDA intends to continue to apply its existing regulations tying orphan-drug exclusivity to the uses or indications for which the orphan drug was approved. We cannot guarantee which rules and interpretations will be governing going forward in different situations, that the FDA will maintain this current position, or that other judicial actions will not impact the FDA’s application of the Orphan Drug Act.

Patent term restoration and extension

A patent claiming a new drug product may be eligible for a limited patent term extension under the Hatch-Waxman Act, which permits a patent restoration of up to five years for patent term lost during product development and the FDA regulatory review. The restoration period granted is typically one-half the time between the effective date of an IND and the submission date of an NDA less any time the applicant did not act with due diligence during the period, plus the time between the submission date of an NDA and the ultimate approval date less any time the applicant did not act with due diligence during the period. Patent term restoration cannot be used to extend the remaining term of a patent past a total of 14 years from the product’s approval date. Only one patent applicable to an approved drug product is eligible for the extension, only those claims covering the approved drug, a method for using it, or a method for manufacturing it may be

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extended, and the application for the extension must be submitted prior to the expiration of the patent in question. A patent that covers multiple drugs for which approval is sought can only be extended in connection with one of the approvals. The USPTO reviews and approves the application for any patent term extension or restoration in consultation with the FDA. Similar provisions are available in Europe and other foreign jurisdictions to extend the term of a patent that covers an approved drug. In the future, if and when our products receive FDA approval, we expect to apply for patent term extensions on patents covering those products. We plan to seek patent term extensions to any of our issued patents in any jurisdiction where these are available, however there is no guarantee that the applicable authorities, including the FDA in the United States, will agree with our assessment of whether such extensions should be granted, and if granted, the length of such extensions. For more information regarding the risks related to our intellectual property, see “Risk Factors—Risks Related to Our Intellectual Property.”

Regulations outside the United States

We will be subject to similar foreign laws and regulations concerning the development of our product candidates outside of the United States in the future.

Coverage and reimbursement

Our ability to commercialize any products successfully will also depend in part on the extent to which coverage and adequate reimbursement for the procedures utilizing our product candidates, performed by health care providers, once approved, will be available from government health administration authorities, private health insurers and other organizations. Government authorities and other third-party payors, such as private health insurers and health maintenance organizations, determine which procedures, and the products utilized in such procedures, they will cover and establish reimbursement levels. Assuming coverage is obtained for procedures utilizing a given product by a third-party payor, the resulting reimbursement payment rates may not be adequate or may require co-payments that patients find unacceptably high. Patients who undergo procedures for the treatment of their conditions, and their treating physicians, generally rely on third-party payors to reimburse all or part of the costs associated with the procedures which utilize our products. Treating physicians are unlikely to use and order our products unless coverage is provided and the reimbursement is adequate to cover all or a significant portion of the cost of the procedures which utilize our products. Therefore, coverage and adequate reimbursement for procedures which utilize new products is critical to the acceptance of such new products. Coverage decisions may depend upon clinical and economic standards that disfavor new products when more established or lower cost therapeutic alternatives are already available or subsequently become available.

Government authorities and other third-party payors are developing increasingly sophisticated methods of cost containment, such as including price controls, restrictions on coverage and reimbursement and requirements for substitution of less expensive products and procedures. Government and other third-party payors are increasingly challenging the prices charged for health care products and procedures, examining the cost effectiveness of procedures, and the products used in such procedures, in addition to their safety and efficacy, and limiting or attempting to limit both coverage and the level of reimbursement. Further, no uniform policy requirement for coverage and reimbursement exists among third-party payors in the United States, which causes significant uncertainty related to the insurance coverage and reimbursement of newly approved products, and the procedures which may utilize such newly approved products. Therefore, coverage and reimbursement can differ significantly from payor to payor and health care provider to health care provider. As a result, the coverage determination process is often a time-consuming and costly process that requires the provision of scientific and clinical support for the use of new products to each payor separately, with no assurance that coverage and adequate reimbursement will be applied consistently or obtained in the first instance.

There may be significant delays in obtaining coverage and reimbursement for newly approved products, and coverage may be more limited than the purposes for which the product is approved by the FDA. Moreover, eligibility for coverage and reimbursement does not imply that a product, or the procedures which utilize such product, will be paid for in all cases or at a rate which the health care providers who purchase those products will find cost effective. Additionally, we expect pricing pressures in connection with the sale of any of our product candidates due to the trend toward managed healthcare, the increasing influence of health maintenance organizations, and additional legislative changes.

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We cannot be sure that coverage and reimbursement will be available for any product that we commercialize, or the procedures which utilize such product, and, if reimbursement is available, what the level of reimbursement will be. Coverage and reimbursement may impact the demand for, or the price of, any product candidate for which we obtain marketing approval. If coverage and reimbursement are not available or reimbursement is available only to limited levels, we may not successfully commercialize any product candidate for which we obtain marketing approval.

Healthcare law and regulation

In the United States, our activities are potentially subject to regulation by various federal, state, and local authorities in addition to the FDA, including but not limited to, CMS, other divisions of the U.S. Department of Health and Human Services (such as the Office of Inspector General, or OIG, and the Health Resources and Service Administration), the U.S. Department of Justice, and individual U.S. Attorney offices, and state and local governments. For example, sales, marketing, and scientific/educational grant programs are subject to the federal Anti-Kickback Statute and the federal False Claims Act, may have to comply with the privacy and security provisions of HIPAA (defined below), and may be subject to similar state laws, each as amended, as applicable. Healthcare providers and third-party payors play a primary role in the recommendation and prescription of drug products that are granted marketing approval. Arrangements with providers, consultants, third-party payors and customers are subject to these broadly applicable healthcare laws and regulations that may constrain our business and/or financial arrangements.

The applicable federal and state healthcare laws and regulations, include, without limitation, the following:

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We expect that one or more of our products, if approved, may be eligible for coverage under Medicare, the federal health care program that provides health care benefits to the aged and disabled, including coverage for outpatient services and supplies, such as certain drug products, that are medically necessary to treat a beneficiary’s health condition. In addition, one or more of our products, if approved, may be covered and reimbursed under other federal health care programs, such as Medicaid and the 340B Drug Pricing Program. The Medicaid Drug Rebate Program requires pharmaceutical manufacturers to enter into and have in effect a national drug rebate agreement with the Secretary of the Department of Health and Human Services in exchange for state Medicaid coverage of most of the manufacturer’s drugs and pay

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quarterly rebates based on utilization of a manufacturer’s covered outpatient drugs under the program as a condition for states to receive federal matching funds for a manufacturer’s covered outpatient drugs furnished to Medicaid patients and in order for payment to be available for a manufacturer’s drugs under Medicare Part B. When a manufacturer markets a new covered outpatient drug (COD), it must also submit product and pricing data concerning the drug to CMS via the Medicaid Drug Programs (MDP) system. Pharmaceutical manufacturers are also required to participate in the 340B Drug Pricing Program, administered by the Health Resources and Services Administration (HRSA) in order for payment to be available for a manufacturer’s drugs under Medicaid and Medicare Part B. Under the 340B Drug Pricing Program, a manufacturer must charge no more than the 340B “ceiling price” for its covered outpatient drugs purchased by statutorily defined covered entities that participate in the program.

In addition, federal law requires that, in order for payment to be available for a manufacturer’s drugs under Medicaid and Medicare Part B, as well as to be purchased by certain federal agencies and grantees, it must also participate in the Department of Veterans Affairs (“VA”) Federal Supply Schedule (“FSS”) pricing program. To participate, manufacturers are required to enter into an FSS contract and other agreements with the VA for their covered drugs. Under these agreements, manufacturers must make their covered drugs available to the “Big Four” federal agencies— the VA, the Department of Defense (“DoD”), the Public Health Service (including the Indian Health Service), and the Coast Guard—at pricing that is capped pursuant to a statutory federal ceiling price, or FCP, formula. The FCP is based on a weighted average non-federal average manufacturer price, which manufacturers are required to report on a quarterly and annual basis to the VA. Further, pursuant to regulations issued by the DoD to implement Section 703 of the National Defense Authorization Act for Fiscal Year 2008, manufacturers may enter into an agreement with the Defense Health Agency (DHA) under which they agree to honor “Big Four” pricing for their covered drugs when they are dispensed to TRICARE beneficiaries by TRICARE retail network pharmacies.

As part of the requirements to participate in these government programs, many pharmaceutical manufacturers must calculate and report certain price reporting metrics to the government, such as average manufacturer price, best price, average sales price, and non-federal average manufacturer price. The calculations can be complex and are often subject to interpretation by manufacturers, governmental or regulatory agencies and the courts. Governmental agencies may also make changes in program interpretations, requirements, or conditions of participation, some of which may have implications for amounts previously estimated or paid. Any failure to comply with these price reporting and rebate payment obligations, when applicable, could negatively impact our financial results. Civil monetary penalties can be applied if a manufacturer is found to have knowingly submitted any false price information to the government, if a manufacturer is found to have made a misrepresentation in the reporting of its average sales price, or if a manufacturer fails to submit the required price data on a timely basis. Such conduct also could be grounds for CMS to terminate a manufacturer’s Medicaid drug rebate agreement, in which case federal payments may not be available under Medicaid or Medicare Part B for a manufacturer’s covered outpatient drugs and may provide a basis for other potential liability under other federal laws such as the False Claims Act.

Efforts to ensure that our business arrangements with third parties will comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices may not comply with current or future statutes, regulations, guidance, case law or other applicable law. If our operations are found to be in violation of any of these laws or any other governmental regulations that may apply to us, we may be subject to significant civil, criminal and administrative penalties, damages, fines, individual imprisonment, exclusion from participation in federal health care programs, such as Medicare and Medicaid, disgorgement, reputational harm, additional oversight and reporting obligations pursuant to a corporate integrity agreement or similar agreement to resolve allegations of non-compliance with applicable laws and regulations, and the curtailment or restructuring of our operations, any of which could adversely affect our ability to market our products, if approved, and adversely impact our financial results. Although effective compliance programs can mitigate the risk of investigation and prosecution for violations of these laws and regulations, these risks cannot be eliminated entirely. Any action against us for an alleged or suspected violation could cause us to incur significant legal expenses and could divert our management’s attention from the operation of our business, even if our defense is successful. If any of the physicians or other healthcare providers or entities with whom we expect to do business is found not to be in compliance with applicable laws, it may be costly to us in terms of money, time and resources, and they may be subject to criminal, civil or administrative sanctions, including exclusion from government-funded healthcare programs.

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U.S. healthcare reform

In the United States and some foreign jurisdictions, there have been and continue to be a number of legislative and regulatory changes and proposed changes regarding the healthcare system that could prevent or delay marketing approval of our product candidates, restrict or regulate post-approval activities and affect our ability, or the ability of our future collaborators, to effectively sell any drugs for which we, or they, obtain marketing approval. We expect that current laws, as well as other healthcare reform measures that may be adopted in the future, may result in more rigorous coverage criteria and additional downward pressure on the price that we, or our future collaborators, may receive for any approved drugs. For example, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act (collectively, “PPACA”) has substantially changed and continues to impact healthcare financing and delivery by both government payors and private insurers. Among the PPACA provisions of importance to the pharmaceutical industry, in addition to those otherwise described above, are the following:

The framework of the PPACA continues to evolve as a result of executive, legislative, regulatory, and administrative developments that have challenged the law and contribute to legal uncertainty that could affect the profitability of our

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products. While Congress has not enacted legislation to comprehensively repeal the PPACA, legislation affecting the PPACA has been signed into law, including the elimination, effective January 1, 2019, of the tax-based shared responsibility payment imposed by the PPACA on certain individuals who fail to maintain qualifying health coverage for all or part of a year, which is commonly referred to as the “individual mandate.” In December 2018, a federal district court in Texas ruled that the PPACA’s individual mandate, without the penalty that was eliminated effective January 1, 2019, was unconstitutional and could not be severed from the PPACA. As a result, the court ruled the remaining provisions of the PPACA were also invalid. The Fifth Circuit Court of Appeals affirmed the district court’s ruling that the individual mandate was unconstitutional, but it remanded the case back to the district court for further analysis of whether the mandate could be severed from the PPACA (i.e., whether the entire PPACA was therefore also unconstitutional). On June 17, 2021, the U.S. Supreme Court dismissed this challenge without specifically ruling on the constitutionality of the PPACA.

Effective January 1, 2019, the Bipartisan Budget Act of 2018, among other things, further amended portions of the Social Security Act implemented as part of the PPACA to increase from 50% to 70% the point-of-sale discount that pharmaceutical manufacturers participating in the Coverage Gap Discount Program must provide to eligible Medicare Part D beneficiaries during the coverage gap phase of the Part D benefit, commonly referred to as the “donut hole,” and to reduce standard beneficiary cost sharing in the coverage gap from 30% to 25% in most Medicare Part D plans. In addition, the Further Consolidated Appropriations Act of 2020, signed into law December 20, 2019, fully repealed the PPACA’s “Cadillac Tax” on certain high-cost employer-sponsored insurance plans (for tax years beginning after December 31, 2019), the annual fee imposed on certain health insurance providers based on market share (for calendar year 2021), and the medical device excise tax on non-exempt medical devices (for sales after December 31, 2019). In the future, there may be additional challenges and/or amendments to the PPACA. It remains to be seen precisely what any new legislation will provide, when or if it will be enacted, and what impact it will have on the availability and cost of healthcare items and services, including drug products.

Most recently, on August 16, 2022 the Inflation Reduction Act of 2022, or IRA was signed into law. Among other things, the IRA requires manufacturers of certain drugs to engage in price negotiations with Medicare (beginning in 2026), with prices that can be negotiated subject to a cap; imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation (first due in 2023); and replaces the Part D coverage gap discount program with a new discounting program (beginning in 2025). The IRA permits the Secretary of the Department of Health and Human Services (HHS) to implement many of these provisions through guidance, as opposed to regulation, for the initial years. For that and other reasons, it is currently unclear how the IRA will be effectuated, and the impact of the IRA on the pharmaceutical industry cannot yet be fully determined. On December 14, 2023, President Biden announced that, through the IRA, dozens of pharmaceutical companies are required to pay rebates to Medicare for price hikes on prescription drugs.

In addition, other legislative changes have been proposed and adopted since the PPACA was enacted. For example, the Budget Control Act of 2011, among other things, resulted in reductions in payments to Medicare providers of 2% per fiscal year, which went into effect on April 1, 2013 and, due to subsequent legislation, will remain in effect through 2031, with the exception of a temporary suspension of the payment reduction from May 1, 2020 through March 31, 2022 due to the coronavirus pandemic. Sequestration will start again on April 1, 2022. From April 1, 2022 to June 30, 2022, payment for Medicare fee-for-service claims will be adjusted downwards by 1%; beginning on July 1, 2022, the payment will be adjusted downwards by 2%. In addition, on March 11, 2021, President Biden signed the American Rescue Plan Act of 2021 into law, which eliminates the statutory Medicaid drug rebate cap, currently set at 100% of a drug’s average manufacturer price, for single source and innovator multiple source drugs, beginning January 1, 2024. These legislative changes may result in additional reductions in Medicare and other healthcare funding and otherwise affect the prices we may obtain for any of our product candidates for which we may obtain regulatory approval or the frequency with which any such product candidate is prescribed or used.

Recently, the cost of prescription pharmaceuticals has been the subject of considerable discussion in the United States. Congress considered and passed legislation, and the former Trump administration pursued several regulatory reforms to further increase transparency around prices and price increases, lower out-of-pocket costs for consumers, and decrease spending on prescription drugs by government programs. Congress also continued to conduct inquiries into the prescription drug industry’s pricing practices. While several proposed reform measures will require Congress to pass

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legislation to become effective, Congress and the Biden administration have each indicated that it will continue to seek new legislative and/or administrative measures to address prescription drug costs. The Biden administration has taken several recent executive actions that signal changes in policy from the prior administration. For example, on July 9, 2021, President Biden signed an executive order to promote competition in the US economy that included several initiatives addressing prescription drugs. Among other provisions, the executive order directed the Secretary of HHS to issue a report to the White House within 45 days that includes a plan to, among other things, reduce prices for prescription drugs, including prices paid by the federal government for such drugs. In response to the Executive Order, on September 9, 2021, HHS issued a Comprehensive Plan for Addressing High Drug Prices that identified potential legislative policies and administrative tools that Congress and the agency can pursue in order to make drug prices more affordable and equitable, improve and promote competition throughout the prescription drug industry, and foster scientific innovation. Additionally, on February 2, 2022, the Biden Administration signaled its continued commitment to the Cancer Moonshot initiative, which was initially launched in 2016. In its recent announcement, the administration noted that its new goals under the initiative include addressing inequities in order to ensure broader access to cutting-edge cancer therapeutics and investing in a robust pipeline for new treatments. At the state level, legislatures are increasingly passing legislation and states are implementing regulations designed to control spending on and patient out-of-pocket costs for drug products. Implementation of cost containment measures or other healthcare reforms that affect the pricing and/or availability of drug products may impact our ability to generate revenue, attain or maintain profitability, or commercialize products for which we may receive regulatory approval in the future.

We expect that these and other healthcare reform measures that may be adopted in the future may result in more rigorous coverage criteria and/or new payment methodologies, and place additional downward pressure on the price that we receive for any approved product and/or the level of reimbursement physicians and other healthcare providers receive for administering any approved product we might bring to market. Reductions in reimbursement levels and imposition of more rigorous coverage criteria or new payment methodologies may negatively impact the prices we receive or the frequency with which our products are prescribed or administered. Any coverage or reimbursement policies instituted by Medicare or other federal health care programs may result in similar policies from private payors. The implementation of cost containment measures or other healthcare reforms may affect our ability to generate revenue, attain or maintain profitability, or commercialize our drug candidates. We expect that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for our drug candidates or additional pricing pressures.

Human Capital Resources and Employees

As of December 31, 2025, we had 8 full-time employees, of which 5 employees are directly engaged in research and development with the rest providing administrative, business and operations support. We also utilize outside consultants and independent contractors to supplement our full-time workforce. None of our employees are represented by a labor union or covered by collective bargaining agreements. We consider the relationship with our employees to be good.

Our human capital resource objectives include, identifying, recruiting, retaining, incentivizing, and integrating our existing and new employees. The principal purpose of our equity incentive plan is to attract, retain and motivate employees and directors through the granting of stock-based compensation awards. Our future performance depends significantly upon the continued service of our key scientific, technical and senior management personnel and our continued ability to attract and retain highly skilled employees. We provide our employees with competitive salaries and bonuses, opportunities for equity ownership, development programs that enable continued learning and growth and a robust employment package that promotes well-being across all aspects of their lives. In addition to salaries, these programs include potential annual discretionary bonuses, stock awards, healthcare and insurance benefits, health savings and flexible spending accounts, paid time off, family leave, and flexible work schedules, among other benefits.

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Information about Our Executive Officers

The following table sets forth certain information about our executive officers as of December 31, 2025.

Name Age Position

Oren Gilad, Ph.D. 57 President and Chief Executive officer

John P. Hamill 61 Senior Vice President, Chief Financial Officer and Secretary

Oren Gilad, Ph.D. has served as Chief Executive Officer of Aprea Therapeutics since July 2022 and as President and a member of its Board of Directors since May 2022. He previously served as President and CEO of Atrin Pharmaceuticals, Inc., leading its transaction with Aprea Therapeutics. Dr. Gilad brings extensive experience across multiple phases of drug development. During his time at Atrin, he led development from idea through early stage into the clinical stage while securing financing to support pre-clinical and clinical development, regulatory, and intellectual property activities. Before founding Atrin in 2011, Dr. Gilad authored several high-impact scientific publications over a 13-year academic career, including one demonstrating the importance of the ATR pathway in cancer development and treatment. Dr. Gilad earned his doctorate from the University of California at Davis and his B.S. from the Hebrew University, Jerusalem, Israel.

John P. Hamill joined Aprea in January 2023 from Windtree Therapeutics where he served as Senior Vice President and Chief Financial Officer since 2020. He brings more than 30 years of financial leadership experience in the pharmaceutical, biopharmaceutical, and clinical research sectors. He has broad-based experience in financial, administrative, information technology, and facility functions, in addition to having successfully completed IPO and follow-on offerings for several pharmaceutical companies. John has also recently provided consulting services to various life science companies, headed up finance at Trevena, Inc., where he was instrumental in successfully raising equity; NephroGenex, Inc., where he actively led the IPO and subsequent financial restructuring and sale of the company; Savient Pharmaceuticals, where he led a sale process resulting in $120 million in proceeds; and PharmaNet where he successfully completed its sale for approximately $250 million, which then became known as PharmaNet Development Group, where he directed financial and administrative operations for the company. John received a B.S. in Accounting and Business and Computer Science from DeSales University and is a certified public accountant.

Environmental Regulations

We believe we are compliant in all material respects with applicable environmental laws. Presently, we do not anticipate such compliance will have a material effect on capital expenditures, earnings, or our competitive position with respect to any of our operations.

Corporate Information

We were incorporated in Delaware in May 2019. Our corporate headquarters are located at 3805 Old Easton Road, Doylestown, Pennsylvania 18902, and our telephone number is (215) 948-4119.

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Available Information

Our corporate website address is www.aprea.com. Information contained on or accessible through our website are not part of this Annual Report on Form 10-K, and inclusion of our website address in this annual report is an inactive textual reference only. We make our Annual Report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and all amendments to those reports available free of charge on our website as soon as reasonably practicable after we file such reports with, or furnish such reports to, the Securities and Exchange Commission, or SEC.

We are a “smaller reporting company,” as such term is defined in Rule 12b-2 of the Exchange Act, meaning that the market value of our common stock held by non-affiliates is less than $700 million and our annual revenue is less than $100 million during the most recently completed fiscal year. We may continue to be a smaller reporting company if either (i) the market value of our common stock held by non-affiliates is less than $250 million or (ii) our annual revenue is less than $100 million during the most recently completed fiscal year and the market value of our common stock held by non-affiliates is less than $700 million. As a smaller reporting company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

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Item 1A. Risk Factors

Our business is subject to substantial risks and uncertainties. Investing in our common stock involves a high degree of risk. You should carefully consider the risk factors below together with the information contained elsewhere in this Annual Report on Form 10-K, including Part II, Item 8 “Financial Statements and Supplementary Data” and Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and in our other public filings in evaluating our business. Any of the risks and uncertainties described below and in our other filings with the SEC, either alone or taken together, could materially and adversely affect our business, financial condition, results of operations, prospects for growth, and the value of an investment in our common stock. In addition, these risks and uncertainties could cause actual results to differ materially from those expressed or implied by forward looking statements contained in this Form 10-K (please read the Cautionary Note Regarding Forward-Looking Statements in this Form 10-K).

Risk Factor Summary

An investment in our securities is subject to various risks, these risks include, among others, the brief bulleted list of our principal risk factors set forth below that make an investment in our company speculative or risky.

Risks related to our financial position and the need for additional capital

Risks related to the discovery, development and commercialization of our product candidates

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Risks related to our dependence on third parties

Risks related to our intellectual property

Risks related to regulatory and marketing approval and other legal compliance matters

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Risks related to our common stock

The summary risk factors described above should be read together with the text of the full risk factors below in this section entitled “Risk Factors” and the other information set forth in this Annual Report on Form 10-K. The risks summarized above or described in full below are not the only risks that we face. Additional risks and uncertainties not precisely known to us or that we currently deem to be immaterial may also materially adversely affect our business, financial condition, results of operations and future growth prospects.

Risks related to our financial position and need for additional capital

We have incurred significant losses in each year since inception. We expect to incur losses for the foreseeable future and may never achieve or maintain profitability.

Since our inception, we have incurred significant losses on an aggregate basis. Our net loss was $12.6 million and $13.0 million for the years ended December 31, 2025 and 2024, respectively. Our accumulated deficit was $333.6 million as of December 31, 2025. We have not generated any commercial revenue to date from sales of any drugs and have financed our operations principally through private placements and the net proceeds received from the initial public offering (IPO) of our common stock. We have devoted substantially all of our efforts to research and development. We expect that it will be several years, if ever, before we have any product candidates ready for commercialization. We expect to continue to incur significant expenses and increasing operating losses for the foreseeable future. The net losses we incur may fluctuate significantly from quarter to quarter.

To become and remain profitable, we must develop, obtain approval for and eventually commercialize a drug or drugs with significant market potential, either on our own or with a collaborator. This will require us to be successful in a range of challenging activities, including completing preclinical studies and clinical trials of our product candidates, obtaining marketing approval for these product candidates, manufacturing, marketing and selling those drugs for which we may obtain marketing approval and establishing and managing any collaborations for the development, marketing and/or commercialization of our product candidates. We may never succeed in these activities and, even if we do, may never generate revenues that are significant or large enough to achieve profitability. If we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis. Our failure to become and remain profitable would decrease the value of our company and could impair our ability to raise capital, maintain our research and development efforts, expand our business and/or continue our operations. A decline in the value of our company could also cause our stockholders to lose all or part of their investment.

Even if we succeed in commercializing one or more of our product candidates, we will continue to incur substantial research and development and other expenditures to develop and market additional product candidates. We may

encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. The size of our future net losses will depend, in part, on the rate of future growth of our expenses and our ability to generate revenue. Our prior losses and expected future losses have had and will continue to have an adverse effect on our stockholders’ equity and working capital.

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Our product candidates, if approved, may not achieve commercial success. Our commercial revenues, if any, will be derived from sales of drugs that we do not expect to be commercially available for many years, if at all. If we are unable to obtain product approvals or generate significant commercial revenues, our business will be materially harmed.

We have identified conditions and events that raise substantial doubt regarding our ability to continue as a going concern.

We have incurred net losses and utilized cash in operations since inception. In addition, as of December 31, 2025, we had approximately $14.6 million in cash and cash equivalents and expect to continue to incur significant cash outflows and incur future additional losses to execute our operating plan. While we intend to finance our cash needs principally through collaborations, strategic alliances, or license agreements with third parties and/or debt or equity financings, there is no assurance that new financing will be available to us on commercially acceptable terms or in the amounts required, if at all. Due to the uncertainty in securing additional funding, and the insufficient amount of cash and cash equivalents as of December 31, 2025, we have concluded that substantial doubt exists about our ability to continue as a going concern within one year after the date of the filing of this Annual Report. If we are unsuccessful in securing sufficient financing, we may need to delay, reduce, or eliminate our research and development programs, which could adversely affect our business prospects, or cease operations.

Our consolidated financial statements included in this Annual Report have been prepared on a going concern basis under which an entity is able to realize its assets and satisfy its liabilities in the ordinary course of business. The consolidated financial statements do not give effect to any adjustments relating to the carrying values and classification of assets and liabilities that would be necessary should we be unable to continue as a going concern within one year after the date that the financial statements are issued.

Our future operations are dependent upon the successful entry into collaborations, strategic alliances, or license agreements with third parties and/or on the identification and successful completion of equity or debt financing and the achievement of profitable operations at an indeterminate time in the future. There can be no assurances that we will be successful in completing these collaborations or alliances, equity or debt financing or in achieving profitability. As such, there can be no assurance that we will be able to continue as a going concern.

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APRE · 10-K · period ended 2025-12-31

Item 1. Business

Item 1A. Risk Factors

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APRE · 10-K · period ended 2025-12-31

Item 1. Business

Item 1A. Risk Factors

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