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UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

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

For the Fiscal Year Ended December 31, 2021

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

For the transition period from ____________ to ____________

Commission File No. 000-16929

SOLIGENIX, INC.

(Exact name of registrant as specified in its charter)

(State or other jurisdiction of (I.R.S. Employer

incorporation or organization) Identification Number)

29 EMMONS DRIVE, SUITE B-10

(Address of principal executive offices) (Zip Code)

(609) 538-8200

(Registrant’s telephone number, including area code)

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

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

Common Stock, par value $0.01 per share SNGX The Nasdaq Capital Market

Securities registered pursuant to Section 12(g) of the Act: None

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

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the 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. (Check one):

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. ☐

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

The aggregate market value of the common stock held by non-affiliates of the registrant was $39,976,044 (assuming, for this purpose, that executive officers, directors and holders of 10% or more of the common stock are affiliates), based on the closing price of the registrant’s common stock as reported on The Nasdaq Capital Market on June 30, 2021.

On March 22, 2022, there were 42,954,091 shares of the registrant’s common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE: None.

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SOLIGENIX, INC.

ANNUAL REPORT ON FORM 10-K

For the Year Ended December 31, 2021

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Item Description Page

Cautionary Note Regarding Forward-Looking Statements ii

Part I

1. Business 1

1A. Risk Factors 29

1B. Unresolved Staff Comments 49

2. Properties 49

3. Legal Proceedings 49

Part II

6. Selected Financial Data 51

8. Financial Statements and Supplementary Data 59

9A. Controls and Procedures 59

9B. Other Information 60

9C. Disclosure Regarding Foreign Jurisdictions 60

Part III

10. Directors, Executive Officers and Corporate Governance 60

11. Executive Compensation 65

14. Principal Accountant Fees and Services 72

Part IV

15. Exhibits and Financial Statement Schedules 73

Signatures 77

Consolidated Financial Statements F-1

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995, that reflect our current expectations about our future results, performance, prospects and opportunities. These forward-looking statements are not guarantees of future performance and are subject to significant risks, uncertainties, assumptions and other factors, which are difficult to predict and may cause actual results to differ materially from those expressed in, or implied by, any forward-looking statements. The forward-looking statements within this report may be identified by words such as “believes,” “anticipates,” “expects,” “intends,” “may,” “would,” “will” and other similar expressions. However, these words are not the exclusive means of identifying these statements. Statements that are not historical facts are based on our current expectations, beliefs, assumptions, estimates, forecasts and projections for our business and the industry and markets related to our business and are forward-looking statements.

Actual outcomes and results may differ materially from what is expressed in such forward-looking statements. Important factors which may affect these actual outcomes and results include, without limitation:

● maintenance and progression of our business strategy;

Except as expressly required by the federal securities laws, we undertake no obligation to publicly update or revise any forward-looking statements to reflect events or circumstances occurring subsequent to the filing of this Form 10-K with the United States (“U.S.”) Securities and Exchange Commission (“the SEC”) or for any other reason. You should carefully review and consider the various disclosures we make in this report and our other reports filed with the SEC that attempt to advise interested parties of the risks, uncertainties and other factors that may affect our business.

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PART I

Item 1. Business

This Annual Report on Form 10-K contains statements of a forward-looking nature relating to future events or our future financial performance. These statements are only predictions and actual events or results may differ materially. In evaluating such statements, you should carefully consider the various factors identified in this report that could cause actual results to differ materially from those indicated in any forward-looking statements, including those set forth in “Risk Factors” in this Annual Report on Form 10-K. See “Cautionary Note Regarding Forward Looking Statements.”

Our Business Overview

We are a late-stage biopharmaceutical company focused on developing and commercializing products to treat rare diseases where there is an unmet medical need. We maintain two active business segments: Specialized BioTherapeutics and Public Health Solutions.

Our Specialized BioTherapeutics business segment is developing and moving toward potential commercialization of HyBryteTM (a proposed proprietary name of HyBryteTM or synthetic hypericin), a novel photodynamic therapy (“PDT”), utilizing topical synthetic hypericin activated with safe visible light for the treatment of cutaneous T-cell lymphoma (“CTCL”). With a successful Phase 3 study completed, regulatory approval is being sought and commercialization activities for this product candidate are being advanced initially in the U.S. Development programs in this business segment also include expansion of synthetic hypericin (SGX302) into psoriasis, our first-in-class innate defense regulator (“IDR”) technology, dusquetide (SGX942) for the treatment of inflammatory diseases, including oral mucositis in head and neck cancer, and proprietary formulations of oral beclomethasone 17,21-dipropionate (“BDP”) for the prevention/treatment of gastrointestinal (“GI”) disorders characterized by severe inflammation including pediatric Crohn’s disease (SGX203).

Our Public Health Solutions business segment includes active development programs for RiVax®, our ricin toxin vaccine candidate and SGX943, our therapeutic candidate for antibiotic resistant and emerging infectious disease and our vaccine programs targeting filoviruses (such as Marburg and Ebola) and CiVaxTM, our vaccine candidate for the prevention of COVID-19 (caused by SARS-CoV-2). The development of our vaccine programs incorporates the use of our proprietary heat stabilization platform technology, known as ThermoVax®. To date, this business segment has been supported with government grant and contract funding from the National Institute of Allergy and Infectious Diseases (“NIAID”), the Biomedical Advanced Research and Development Authority (“BARDA”) and the Defense Threat Reduction Agency (“DTRA”).

An outline of our business strategy follows:

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Corporate Information

We were incorporated in Delaware in 1987 under the name Biological Therapeutics, Inc. In 1987, we merged with Biological Therapeutics, Inc., a North Dakota corporation, pursuant to which we changed our name to “Immunotherapeutics, Inc.” We changed our name to “Endorex Corp.” in 1996, to “Endorex Corporation” in 1998, to “DOR BioPharma, Inc.” in 2001, and finally to “Soligenix, Inc.” in 2009. Our principal executive offices are located at 29 Emmons Drive, Suite B-10, Princeton, New Jersey 08540 and our telephone number is (609) 538-8200.

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Our Product Candidates in Development

The following tables summarize our product candidates under development:

Specialized BioTherapeutics Product Candidates*

Soligenix Product Candidate Therapeutic Indication Stage of Development

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Public Health Solutions*†

SGX943 Therapeutic against EmergingInfectious Diseases Pre-clinical

CiVaxTM Vaccine against COVID-19 Pre-clinical

* Timelines subject to potential disruption due to COVID-19 outbreak.

Specialized BioTherapeutics Overview

Synthetic Hypericin

Synthetic Hypericin is a potent photosensitizer that is topically applied to skin lesions, taken up by cutaneous T-cells and then activated by safe visible light. Hypericin is also found in several species of Hypericum plants, although this active moiety is chemically synthesized by a proprietary manufacturing process and not extracted from plants. Importantly, hypericin is optimally activated with visible light thereby avoiding the negative consequences of ultraviolet (“UV”) light. Other light therapies using UVA or UVB light can result in serious adverse effects including secondary skin cancers.

Combined with photoactivation, in clinical trials synthetic hypericin has demonstrated significant anti-proliferative effects on activated normal human lymphoid cells and inhibited growth of malignant T-cells isolated from CTCL patients. In both settings, it appears that the mode of action is an induction of cell death in a concentration as well as a light dose-dependent fashion. These effects appear to result, in part, from the generation of singlet oxygen during photoactivation of hypericin.

Synthetic hypericin is one of the most efficient known generators of singlet oxygen, the key component for phototherapy. The generation of singlet oxygen induces necrosis and apoptosis in adjacent cells. The use of topical synthetic hypericin coupled with directed visible light results in generation of singlet oxygen only at the treated site. We believe that the use of visible light (as opposed to cancer-causing UV light) is a major advance in photodynamic therapy. In a small published Phase 1/2 proof of concept pilot clinical study using synthetic hypericin twice weekly for six weeks, statistically significant efficacy was demonstrated in patients with CTCL (58.3% response, p=0.04) and psoriasis (80% response, p<0.02). Subsequently, a pivotal Phase 3 study in CTCL has further confirmed the biological efficacy of synthetic hypericin (termed HyBryteTM in the context of CTCL).

HyBryteTM – for Treating Cutaneous T-Cell Lymphoma

HyBryteTM is a novel, first-in-class, PDT, that utilizes safe visible light for activation. The active ingredient in HyBryteTM is synthetic hypericin, a photosensitizer which is topically applied to skin lesions and then activated by visible fluorescent light 16 to 24 hours later.

Based on the positive and previously published Phase 1/2 results, we initiated our pivotal Phase 3 clinical study of HyBryteTM for the treatment of CTCL during December 2015 and completed the trial in 2020. This trial, referred to as the “FLASH” study (Fluorescent Light Activated Synthetic Hypericin), aimed to evaluate the response to HyBryteTM as a skin directed therapy to treat early stage CTCL. We completed the study with approximately 35 CTCL centers across the U.S. participating in this pivotal trial. The Phase 3 protocol was a highly powered, double-blind, randomized, placebo-controlled, multicenter trial that enrolled 169 subjects (166 evaluable). The trial consisted of three treatment cycles, each of eight weeks duration. Treatments were administered twice weekly for the first six weeks and treatment response was determined at the end of the eighth week. In the first treatment cycle, approximately 66% of subjects received HyBryteTM and 33% received placebo

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treatment of their index lesions. In the second cycle, all subjects received HyBryteTM treatment of their index lesions, and in the third cycle, all subjects received HyBryteTM treatment of all of their lesions. The majority of subjects enrolled elected to continue into the third optional, open-label cycle of the study. Subjects were followed for an additional six months after their last evaluation visit. The primary efficacy endpoint was assessed on the percentage of patients in each of the two treatment groups (i.e., HyBryteTM and placebo) achieving a partial or complete response of the treated lesions, defined as a ≥ 50% reduction in the total Composite Assessment of Index Lesion Disease Severity (“CAILS”) score for three index lesions at the Cycle 1 evaluation visit (Week 8) compared to the total CAILS score at baseline. Secondary endpoints for the trial included the duration of responses, the extent of the regression of the tumors, and the safety of the treatment. We continue to work closely with the Cutaneous Lymphoma Foundation, as well as the National Organization for Rare Disorders.

Positive primary endpoint analysis for the Phase 3 study for HyBryteTM was completed in March 2020. The study enrolled 169 patients (166 evaluable) randomized 2:1 to receive either HyBryteTM (116 patients) or placebo (50 patients) and demonstrated a statistically significant treatment response (p=0.04) in the CAILS primary endpoint assessment at 8 weeks for Cycle 1. A total of 16% of the patients receiving HyBryteTM achieved at least a 50% reduction in their index lesions compared to only 4% of patients in the placebo group at 8 weeks. HyBryteTM treatment in the first cycle was safe and well tolerated.

Analysis of the second open-label treatment cycle (Cycle 2) was completed in April 2020, showing that continued treatment with HyBryteTM twice weekly for an additional 6 weeks (12 weeks total) increased the positive response rate to 40% (p<0.0001 compared to placebo and p<0.0001 compared to 6-weeks treatment). After the subsequent additional 6-week treatment, the response rate in patients receiving a total of 12 weeks treatment increased two and a half-fold. Treatment responses were assessed at Week 8 (after 6 weeks of treatment) and at Week 16 (after 12 weeks of treatment). A positive response was defined as an improvement of at least 50% in the CAILS score for the three index lesions evaluated in both Cycles 1 and 2. The data continued to indicate that HyBryteTM is safe and well tolerated.

Analysis of the optional third open-label treatment cycle (Cycle 3) was completed in October 2020. Cycle 3 was focused on safety and all patients could elect to receive HyBryteTM treatment of all their lesions for an additional 6 weeks or up to 18 weeks in total. Of note, 66% of patients elected to continue with this optional safety cycle of the study. Of the subset of patients that received HyBryteTM throughout all three cycles of treatment (18 weeks), 49% of them demonstrated a treatment response (p=0.046 vs. patients completing 12 weeks of HyBryteTM treatment in Cycle 2; p<0.0001 vs. patients receiving placebo in Cycle 1). Moreover, in a subset of patients evaluated in this cycle, it was demonstrated that HyBryteTM is not systemically available, consistent with the general safety of this topical product observed to date. At the end of Cycle 3, HyBryteTM continued to be well tolerated despite extended and increased use of the product to treat multiple lesions.

In addition, continued analysis of results from the protocol mandated efficacy cycles (Cycles 1 and 2) of the study revealed that 12 weeks of treatment (Cycle 2) with HyBryteTM is equally effective on both patch (response 37%, p=0.0009) and plaque (response 42%, p<0.0001) lesions when compared to Cycle 1 placebo lesion responses, further demonstrating the unique benefits of the more deeply penetrating visible light activation of hypericin.

HyBryteTM has received Orphan Drug designation as well as Fast Track designation from the FDA. The Orphan Drug Act is intended to assist and encourage companies to develop safe and effective therapies for the treatment of rare diseases and disorders. In addition to providing a seven-year term of market exclusivity for HyBryteTM upon final FDA approval, Orphan Drug designation also positions us to be able to leverage a wide range of financial and regulatory benefits, including government grants for conducting clinical trials, waiver of FDA user fees for the potential submission of an NDA for HyBryteTM, and certain tax credits. In addition, Fast Track is a designation that the FDA reserves for a drug intended to treat a serious or life-threatening condition and one that demonstrates the potential to address an unmet medical need for the condition. Fast Track designation is designed to facilitate the development and expedite the review of new drugs. For instance, should events warrant, we will be eligible to submit an NDA for HyBryteTM on a rolling basis, permitting the FDA to review sections of the NDA prior to receiving the complete submission. Additionally, NDAs for Fast Track development programs ordinarily will be eligible for priority review. HyBryteTM for the treatment of CTCL also was granted Orphan Drug designation from the European Medicines Agency (“EMA”) Committee for Orphan Medical Products and Promising Innovative Medicine (“PIM”) designation from the MHRA, as well as Innovation Passport under the Innovative Licensing and Access Pathway (“ILAP”) in the UK.

The U.S. Patent Office granted us a patent titled “Systems and Methods for Producing Synthetic Hypericin” for the unique proprietary process manufacturing the highly purified form of synthetic hypericin, the active pharmaceutical ingredient (“API”) in HyBryteTM, in August 2018.

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The U.S. Patent Office allowed the divisional patent application titled “Systems and Methods for Producing Synthetic Hypericin” in October 2019. The allowed claims are directed to unique, proprietary methods to produce a novel, highly purified form of synthetic hypericin. This new divisional claim set expands on the previous issued claims in the parent U.S. patent.

The European patent office granted the divisional patent application titled “Formulations and Methods of Treatment of Skin Conditions” (No. 2932973) in April 2020. The granted claims are directed to the therapeutic use of synthetic hypericin in the treatment of CTCL. This new patent expands on our comprehensive patent estate, which includes protection on the composition of the purified synthetic hypericin, methods of synthesis and therapeutic methods of use in both CTCL and psoriasis, and is being pursued worldwide.

During January 2021, we signed an exclusive Supply, Distribution and Services Agreement with The Daavlin Distributing Co. (“Daavlin”), securing long-term supply and distribution of a commercially ready light device, which is an integral component of the regulatory and commercial strategy for HyBryteTM for the treatment of CTCL. Pursuant to the agreement, Daavlin will exclusively manufacture the proprietary light device for use with HyBryteTM for the treatment of CTCL. Upon approval of HyBryteTM by the FDA, we will promote HyBryteTM and the companion light device, and facilitate the direct purchase of the device from Daavlin. Daavlin will exclusively distribute and sell the HyBryteTM light device to us, physicians and patients.

The Hong Kong Registrar of Patents granted a patent for the application titled “Formulations and Methods of Treatment of Skin Conditions” (No. 16102842.8), published on January 29, 2021 under Publication No. 1214771 B. The granted claims are directed to the therapeutic use of synthetic hypericin in the treatment of CTCL, similar to those granted in Europe in 2020. This new patent is the first granted in Hong Kong and expands on our comprehensive patent estate, which includes protection on the composition of the purified synthetic hypericin, methods of synthesis and therapeutic methods of use in both CTCL and psoriasis.

In April 2021, the FDA conditionally accepted HyBryteTM as the proposed brand name for SGX301 or synthetic hypericin, in the treatment of early stage CTCL. The name HyBryteTM was developed in compliance with the FDA’s Guidance for Industry, Contents of a Complete Submission for the Evaluation of Proprietary Names. The FDA’s conditional approval validates HyBryteTM as a proprietary name that is consistent with the FDA’s goal of preventing medication errors and potential harm to the public by ensuring that only appropriate proprietary names are approved for use. Final approval of the HyBryteTM proprietary name is conditioned on FDA approval of the product candidate, SGX301.

In May 2021, HyBryteTM was awarded an "Innovation Passport" for the treatment of early stage CTCL in adults under the UK’s ILAP. The decision to award the Innovation Passport to the HyBryteTM program was made by the Innovative Licensing and Access Pathway Steering Group, which is comprised of representatives from MHRA, the National Institute for Health and Care Excellence (“NICE”), and the Scottish Medicines Consortium (“SMC”). ILAP was launched at the start of 2021 to accelerate the development and access to promising medicines, thereby facilitating patient access to new medicines. The pathway, part of the UK’s plan to attract life sciences development in the post-Brexit era, features enhanced input and interactions with the MHRA, NICE, and SMC. The innovation passport designation is the first step in the ILAP process and triggers the MHRA and its partner agencies to create a target development profile to chart out a roadmap for regulatory and development milestones with the goal of early patient access in the UK. Other benefits of ILAP include a 150-day accelerated assessment, rolling review and a continuous benefit risk assessment.

As a result of discussions with the FDA regarding the HyBryteTM NDA submission and due to disruptions caused by the global COVID-19 pandemic resulting in delays by the commercial API contract manufacturer affecting the timing of availability of the pre-requisite amount of accrued stability data required to file the NDA, we plan to file the NDA with the FDA in the second half of 2022 with the corresponding potential FDA approval in the second half of 2023. We currently do not plan to pursue a rolling NDA submission, so that we may provide additional supportive data in the NDA filing. We now plan to submit the NDA in the second half of 2022.

The Japan Patent Office allowed the patent application title “Systems and Methods for Producing Synthetic Hypericin” in May 2021. The allowed claims are directed to unique, proprietary methods to produce a novel, highly purified form of synthetic hypericin, and are similar to those previously allowed in the U.S. This new patent is the first allowed in Japan covering the proprietary methods developed by us and further expands the comprehensive HyBryteTM patent estate, which includes protection of the composition of the purified synthetic hypericin, methods of synthesis and therapeutic methods of use in both CTCL and psoriasis, and is being pursued worldwide.

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In June 2021, we received a Paediatric Investigation Plan (“PIP”) waiver from the EMA for HyBryteTM. As part of the regulatory process for the registration of new medicines with the EMA, pharmaceutical companies are required to provide a PIP outlining their strategies for investigation of the new medicinal products in the pediatric population. In some instances, a waiver negating the need for a PIP for certain conditions may be granted by the EMA when development of a medicine for use in children is not feasible or appropriate, as is the case for HyBryteTM in CTCL which is extremely rare in children.

In September 2021, we were granted orphan drug designation for the active ingredient hypericin for the treatment of T-cell lymphoma, extending the target population beyond CTCL as previously granted by the FDA.

We estimate the potential worldwide market for HyBryteTM is in excess of $250 million for the treatment of CTCL. This potential market information is a forward-looking statement, and investors are urged not to place undue reliance on this statement. While we have determined this potential market size based on assumptions that we believe are reasonable, there are a number of factors that could cause our expectations to change or not be realized.

Cutaneous T-Cell Lymphoma

CTCL is a class of non-Hodgkin’s lymphoma (“NHL”), a type of cancer of the white blood cells that are an integral part of the immune system. Unlike most NHLs, which generally involve B-cell lymphocytes (involved in producing antibodies), CTCL is caused by an expansion of malignant T-cell lymphocytes (involved in cell-mediated immunity) normally programmed to migrate to the skin. These skin-trafficking malignant T-cells migrate to the skin, causing various lesions to appear that may change shape as the disease progresses, typically beginning as a rash and eventually forming plaques and tumors. Mycosis fungoides (“MF”) is the most common form of CTCL. It generally presents with skin involvement only, manifested as scaly, erythematous patches. Advanced disease with diffuse lymph node and visceral organ involvement is usually associated with a poorer response rate to standard therapies. A relatively uncommon sub-group of CTCL patients present with extensive skin involvement and circulating malignant cerebriform T-cells, referred to as Sézary syndrome. These patients have substantially graver prognoses (expected five-year survival rate of 24%), than those with MF (expected five-year survival rate of 88%).

CTCL mortality is related to stage of disease, with median survival generally ranging from about 12 years in the early stages to only 2.5 years when the disease has advanced. There is currently no FDA-approved drug for front-line treatment of early stage CTCL. Treatment of early-stage disease generally involves skin-directed therapies. One of the most common unapproved therapies used for early-stage disease is oral 5 or 8-methoxypsoralen (“Psoralen”) given with ultraviolet A (“UVA”) light, referred to as PUVA, which is approved for dermatological conditions such as disabling psoriasis not adequately responsive to other forms of therapy, idiopathic vitiligo and skin manifestations of CTCL in persons who have not been responsive to other forms of treatment. Psoralen is a mutagenic chemical that interferes with DNA causing mutations and other malignancies. Moreover, UVA is a carcinogenic light source that when combined with the Psoralen, results in serious adverse effects including secondary skin cancers; therefore, the FDA requires a Black Box warning for PUVA.

CTCL constitutes a rare group of NHLs, occurring in about 4% of the approximate 500,000 individuals living with NHL. We estimate, based upon review of historic published studies and reports and an interpolation of data on the incidence of CTCL, that it affects over 20,000 individuals in the U.S., with approximately 2,800 new cases seen annually.

SGX302 – for Treating Mild-to-Moderate Psoriasis

SGX302 (synthetic hypericin) is a potent photosensitizer that is topically applied to skin lesions and taken up by cutaneous T-cells. With subsequent activation by safe, visible light, T-cell apoptosis is induced, addressing the root cause of psoriasis lesions. Other PDTs have shown efficacy in psoriasis with a similar apoptotic mechanism, albeit using UV light associated with more severe potential long-term toxicities. The use of visible light in the red-yellow spectrum has the advantage of deeper penetration into the skin (much more than UV light) potentially treating deeper skin disease and thicker plaques and lesions, similar to what was observed in the positive Phase 3 FLASH study in CTCL. Further, this treatment approach avoids the risk of secondary malignancies (including melanoma) inherent with both the frequently used DNA-damaging drugs and other phototherapies that are dependent on UV A or UV B exposure. The use of SGX302 coupled with safe, visible light also avoids the risk of serious infections and cancer associated with the systemic immunosuppressive treatments used in psoriasis.

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In September 2021, we announced that following the validation of synthetic hypericin’s biologic activity in the positive pivotal Phase 3 FLASH study in CTCL, as well as positive proof-of-concept demonstrated in a small Phase 1/2 pilot study in mild-to-moderate psoriasis patients, we will be expanding this novel therapy into a Phase 2a clinical trial in mild-to-moderate psoriasis. We will provide further details regarding trial design and timeline; however, our high level plan in the interim is to evaluate different topical formulations of synthetic hypericin to ensure optimal absorption for broadly treating this disease. In parallel, we will be working with our psoriasis clinical experts to finalize a protocol with a plan to initiate study enrollment in the latter part of 2022. We estimate the potential worldwide market for SGX302 to be in excess of $1 billion for the treatment of mild-to-moderate psoriasis. This potential market information is a forward-looking statement, and investors are urged not to place undue reliance on this statement. While we have determined this potential market size based on assumptions that we believe are reasonable, there are a number of factors that could cause our expectations to change or not be realized.

Psoriasis

Psoriasis is a chronic, non-communicable, itchy and often painful inflammatory skin condition for which there is no cure. Psoriasis has a significantly detrimental impact on patients' quality of life, and is associated with cardiovascular, arthritic, and metabolic diseases, as well as psychological conditions such as anxiety, depression and suicide. Many factors contribute to development of psoriasis including both genetic and environmental factors (e.g., skin trauma, infections, and medications). The lesions develop because of rapidly proliferating skin cells, driven by autoimmune T-cell mediated inflammation. Of the various types of psoriasis, plaque psoriasis is the most common and is characterized by dry, red raised plaques that are covered by silvery-white scales occurring most commonly on the elbows, knees, scalp, and lower back. Approximately 80% of patients have mild-to-moderate disease. Mild psoriasis is generally characterized by the involvement of less than 3% of the body surface area (“BSA”), while moderate psoriasis will typically involve 3-10% BSA and severe psoriasis greater than 10% BSA. Between 20% and 30% of individuals with psoriasis will go on to develop chronic, inflammatory arthritis (psoriatic arthritis) that can lead to joint deformations and disability. Studies have also associated psoriasis, and particularly severe psoriasis, with an increased relative risk of lymphoma, particularly CTCL. Although psoriasis can occur at any age, most patients present with the condition before age 35.

Treatment of psoriasis is based on its severity at the time of presentation with the goal of controlling symptoms. It varies from topical options including PDT to reduce pain and itching, and potentially reduce the inflammation driving plaque formation, to systemic treatments for more severe disease. Most common systemic treatments and even current topical photo/photodynamic therapy such as UV A and B, carry a risk of increased skin cancer.

Psoriasis is the most common immune-mediated inflammatory skin disease. According to the World Health Organization (“WHO”) Global Report on Psoriasis 2016, the prevalence of psoriasis is between 1.5% and 5% in most developed countries, with some suggestions of incidence increasing with time. It is estimated, based upon review of historic published studies and reports and an interpolation of data that psoriasis affects 3% of the U.S. population or more than 7.5 million people. Current estimates have as many as 60-125 million people worldwide living with the condition. The global psoriasis treatment market was valued at approximately $15 billion in 2020 and is projected to reach as much as $40 billion by 2027.

Dusquetide

Dusquetide (research name: SGX94) is an IDR that regulates the innate immune system to simultaneously reduce inflammation, eliminate infection and enhance tissue healing.

Dusquetide is based on a new class of short, synthetic peptides known as IDRs. It has a novel mechanism of action in that it modulates the body’s reaction to both injury and infection and is both simultaneously anti-inflammatory and anti-infective. IDRs have no direct antibiotic activity but modulate host responses, increasing survival after infections with a broad range of bacterial Gram-negative and Gram-positive pathogens including both antibiotic sensitive and resistant strains, as well as accelerating resolution of tissue damage following exposure to a variety of agents including bacterial pathogens, trauma and chemo- or radiation-therapy. IDRs represent a novel approach to the control of infection and tissue damage via highly selective binding to an intracellular adaptor protein, sequestosome-1, also known as p62, which has a pivotal function in signal transduction during activation and control of the innate defense system. Preclinical data indicate that IDRs may be active in models of a wide range of therapeutic indications including life-threatening bacterial infections as well as the severe side-effects of chemo- and radiation-therapy. Additionally, due to selective binding to p62, dusquetide may have potential anti-tumor action.

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Dusquetide has demonstrated efficacy in numerous animal disease models including mucositis, oncology, colitis, skin infection and other bacterial infections and has been evaluated in a double-blind, placebo-controlled Phase 1 clinical trial in 84 healthy volunteers with both single ascending dose and multiple ascending dose components. Dusquetide was shown to have a good safety profile and be well-tolerated in all dose groups when administered by IV over 7 days and was consistent with safety results seen in pre-clinical studies. We believe that market opportunities for dusquetide include, but are not limited to, oral and gastrointestinal mucositis, oncology (e.g., breast cancer), acute Gram-positive bacterial infections (e.g., methicillin resistant Staphylococcus aureus (“MRSA”)), acute Gram-negative infections (e.g., acinetobacter, melioidosis), and acute radiation syndrome.

SGX942 – for Treating Oral Mucositis in Head and Neck Cancer

SGX942 is our product candidate containing our IDR technology, dusquetide, targeting the treatment of oral mucositis in head and neck cancer patients. Oral mucositis in this patient population is an area of unmet medical need where there are currently no approved drug therapies. Accordingly, we received Fast Track designation for the treatment of oral mucositis as a result of radiation and/or chemotherapy treatment in head and neck cancer patients from the FDA. In addition, dusquetide has been granted PIM designation in the UK by the MHRA for the treatment of severe oral mucositis in head and neck cancer patients receiving chemoradiation therapy. The U.S. Patent and Trademark Office and the European Patent Office granted us the patent titled “Novel Peptides and Analogs for Use in the Treatment of Oral Mucositis” in August 2016 and January 2019, respectively. The newly issued patent claims therapeutic use of dusquetide and related IDR analogs, and adds to composition of matter claims for dusquetide and related analogs that have been granted in the U.S. and worldwide.

We initiated a Phase 2 clinical study of SGX942 for the treatment of oral mucositis in head and neck cancer patients in December of 2013. We completed enrollment in this trial in the second half of 2015, and in December 2015 released positive preliminary results. In this Phase 2 proof-of-concept clinical study that enrolled 111 patients, SGX942, at a dose of 1.5 mg/kg, successfully reduced the median duration of SOM by 50%, from 18 days to 9 days (p=0.099) in all patients and by 67%, from 30 days to 10 days (p=0.040) in patients receiving the most aggressive chemoradiation therapy for treatment of their head and neck cancer. The p-values met the prospectively defined statistical threshold of p<0.1 in the study protocol. A less severe occurrence of oral mucositis, ulcerative oral mucositis (defined as oral mucositis with a WHO score ≥2 corresponding to the occurrence of overt ulceration in the mouth), was also monitored during the study. In the patients receiving the most aggressive chemoradiation therapy, the median duration of oral mucositis was found to decrease from 65 days in the placebo treated patients to 51 days in the patients treated with SGX942 1.5 mg/kg (p=0.099).

In addition to identifying the best dose of 1.5 mg/kg, this study achieved all objectives, including increased incidence of “complete response” of tumor at the one month follow-up visit (47% in placebo vs. 63% in SGX942 at 1.5 mg/kg). Decreases in mortality and decreases in infection rate were also observed with SGX942 treatment, consistent with the preclinical results observed in animal models.

SGX942 was found to be generally safe and well tolerated, consistent with the safety profile observed in the prior Phase 1 study conducted in 84 healthy volunteers. The long-term (12 month) follow-up data was consistent with the preliminary positive safety and efficacy findings. While the placebo population experienced the expected 12-month survival rate of approximately 80%, as defined in the Surveillance, Epidemiology, and End Results statistics 1975-2012 from the National Cancer Institute, the SGX942 1.5 mg/kg treatment group reported a 12-month survival rate of 93% (7% mortality in the SGX942 1.5 mg/kg group compared to 19% in the placebo group). Similarly, tumor resolution (complete response) at 12 months was better in the SGX942 1.5 mg/kg treatment group relative to the placebo population (80% in the 1.5 mg/kg group compared to 74% in the placebo group). Moreover, in the patients receiving chemotherapy every third week, the SGX942 1.5 mg/kg treatment group had a tumor resolution rate (complete response) of 82% throughout the 12 months following chemoradiation therapy, while the placebo group experienced a 64% complete response rate. The long-term follow-up results from the Phase 2 study are reviewed in “Dusquetide: Reduction in Oral Mucositis associated with Enduring Ancillary Benefits in Tumor Resolution and Decreased Mortality in Head and Neck Cancer Patients” published online in Biotechnology Reports and available at the following link: https://doi.org/10.1016/j.btre.2017.05.002. In addition to safety, evaluations of other secondary efficacy endpoints, such as the utilization of opioid pain medication, indicated that the SGX942 1.5 mg/kg treatment group had a 40% decrease in the use of opioids at the later stage of the treatment phase of the trial, when oral mucositis is usually most severe and expected to increase pain medication use. This was in contrast to the placebo group, which demonstrated a 10% increase in use of opioids over this same period. Data from this Phase 2 trial was published online in the Journal of Biotechnology. The publication also delineates the supportive nonclinical data in this indication, demonstrating consistency in the qualitative and quantitative biological response, including dose response,

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across the nonclinical and clinical data sets. The results are available at the following link: http://authors.elservier.com/sd/article/S01681656116315668.

In September 2016, we and SciClone Pharmaceuticals, Inc. (“SciClone”) entered into an exclusive license agreement, pursuant to which we granted rights to SciClone to develop, promote, market, distribute and sell SGX942 in defined territories. Under the terms of the license agreement, SciClone will be responsible for all aspects of development, product registration and commercialization in the territories, having access to data generated by us. In exchange for exclusive rights, SciClone will pay us royalties on net sales, and we will supply commercial drug product to SciClone on a cost-plus basis, while maintaining worldwide manufacturing rights.

During July 2017, we initiated our pivotal Phase 3 clinical trial referred to as the “DOM–INNATE” study (Dusquetide treatment in Oral Mucositis – by modulating INNATE immunity) with a controlled roll-out of U.S. study sites, followed by the addition of European centers in 2018. Approximately 50 U.S. and European oncology centers are participating in this pivotal Phase 3 study. Based on the positive and previously published Phase 2 results (Study IDR-OM-01), the pivotal Phase 3 clinical trial (Study IDR-OM-02) was a highly powered, double-blind, randomized, placebo-controlled, multinational trial that sought to enroll approximately 260 subjects with squamous cell carcinoma of the oral cavity and oropharynx who were scheduled to receive a minimum total cumulative radiation dose of 55 Gy fractionated as 2.0-2.2 Gy per day with concomitant cisplatin chemotherapy given as a dose of 80-100 mg/m2 every third week. Subjects were randomized to receive either 1.5 mg/kg SGX942 or placebo given twice a week during and for two weeks following completion of chemoradiation therapy (“CRT”). The primary endpoint for the study was the median duration of SOM, which was assessed by oral examination at each treatment visit and then through six weeks following completion of CRT. Oral mucositis is evaluated using the WHO Grading system. SOM is defined as a WHO Grade of ≥3. Subjects are followed for an additional 12 months after the completion of treatment.

The U.S. Patent Office issued a new patent No. 10,253,068 titled “Novel Peptides for Treating and Preventing Immune-Related Disorders, Including Treating and Preventing Infection by Modulating Innate Immunity” for our dusquetide related analogs in April 2019.

In April 2019, the Paediatric Committee of the EMA approved our PIP for SGX942, a prerequisite for filing a Marketing Authorization Application (“MAA”) for any new medicinal product in Europe. The EMA also agreed that we may defer conducting the PIP until successful completion of our ongoing pivotal Phase 3 clinical trial of SGX942, which allows us to file the adult indication MAA prior to completion of the PIP.

During August 2019, an independent DMC completed an unblinded interim analysis with data from approximately 90 subjects, including an assessment of the Phase 3 DOM-INNATE study’s primary efficacy endpoint. The DMC provided a positive recommendation to randomize approximately 70 additional subjects into the trial to maintain the rigorous assumption of 90% statistical power for the primary efficacy endpoint. No safety concerns were reported by the DMC based on the interim analysis.

The Japanese Patent Office granted the patent titled “Novel Peptides and Analogs for Use in the Treatment of Oral Mucositis” in February 2020. This allowance builds on similar intellectual property in the U.S., New Zealand, Australia and Singapore and patent applications pending in other jurisdictions worldwide. The new claims cover therapeutic use of dusquetide (active ingredient in SGX942) and related IDR analogs, and add to composition of matter claims for dusquetide and related analogs that have been granted in the U.S. and worldwide.

In June 2020, the pivotal Phase 3 DOM–INNATE study (Study IDR-OM-02) completed enrollment of 268 subjects. In December 2020, the results of our Phase 3 clinical trial for SGX942 showed that the primary endpoint of median duration of SOM did not achieve the pre-specified criterion for statistical significance (p≤0.05); although biological activity was observed with a 56% reduction in the median duration of SOM from 18 days in the placebo group to 8 days in the SGX942 treatment group. Despite this clinically meaningful improvement, the variability in the distribution of the data yielded a p-value that was not statistically significant. Other secondary endpoints supported the biological activity of dusquetide, including a statistically significant 50% reduction in the median duration of SOM in the per-protocol population, which decreased from 18 days in the placebo group to 9 days in the SGX942 treatment group (p=0.049), consistent with the findings in the Phase 2 trial (Study IDR-OM-01). Similarly, incidence of SOM also followed this biological trend as seen in the Phase 2 study, decreasing by 16% in the SGX942 treatment group relative to the placebo group in the per-protocol population. The per-protocol population was defined as the population receiving a minimum of 55 Gy radiation and at least

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10 doses of study drug (placebo or SGX942) throughout the intended treatment period, with no major protocol deviations (e.g. breaks in study drug administration longer than 8 days between successive doses).

Following analysis of the full dataset, including the 12-month long-term follow-up safety data in late 2021, we held a meeting with the MHRA to review the study results and to obtain further clarity on the future of the oral mucositis development program. The meeting was informative with the outcome being that based on the SGX942 biologic activity observed and the consistency in response between the Phase 2 and Phase 3 trials, the Phase 3 DOM-INNATE study could serve as the first of two Phase 3 studies required to support potential marketing authorization, assuming the second Phase 3 clinical trial achieves the required level of statistical significance in its primary endpoint. Importantly, we also have further investigated the impact of SGX942 (dusquetide) on tumor burden in preclinical xenograft studies. These studies, similar to previous results, continued to demonstrate a potential direct anti-tumor effect of SGX942. This additional benefit of SGX942 is an important consideration in the oral mucositis treatment space. Other competitive considerations with SGX942 include its safety and ease of use. In particular, SGX942 is administered as a short 4-minute intravenous (IV) infusion twice weekly. This contrasts significantly with Galera Therapeutics Inc.’s recently completed Phase 3 oral mucositis study with Avasopasem. From what is available publicly, Avasopasem must be administered daily with radiation, within a short window of time of that daily radiation treatment and takes 60 minutes to administer by IV infusion. Interestingly, the recently reported incidence change observed in the Phase 3 Avasopasem trial (64% incidence in placebo, 54% treated) is favorably compared with the incidence change in the DOM-INNATE study (68% placebo, 58% SGX942). As well, the decrease in duration of SOM was similar between the two studies (18 days for placebo vs. 8 days for active in both studies). Given some of the recently announced complications with the Avasopasem results, and the significant inconveniences and logistical hurdles with its use, we continue to believe that SGX942 is the superior product. With the benefit of a robust preclinical and clinical data package for SGX942, we now will be analyzing the existing Phase 3 dataset from the DOM-INNATE study to design a second Phase 3 study and will look to identify a potential partner(s) to continue this development program.

In January 2022, we announced that dusquetide is effective at reducing tumor size in nonclinical xenograft models. Recent studies, recapitulating results from previously published studies, have confirmed the efficacy of dusquetide as a stand-alone and combination anti-tumor therapy, with radiation, chemotherapy and targeted therapy, in the context of the MCF-7 breast cancer cell line.

Oral Mucositis

Mucositis is the clinical term for damage done to the mucosa by anticancer therapies. It can occur in any mucosal region, but is most commonly associated with the mouth, followed by the small intestine. We estimate, based upon our review of historic studies and reports, and an interpolation of data on the incidence of mucositis, that mucositis affects approximately 500,000 people in the U.S. per year and occurs in 40% of patients receiving chemotherapy. Mucositis can be severely debilitating and can lead to infection, sepsis, the need for parenteral nutrition and narcotic analgesia. The GI damage causes severe diarrhea. These symptoms can limit the doses and duration of cancer treatment, leading to sub-optimal treatment outcomes.

The mechanisms of mucositis have been extensively studied and have been linked to the interaction of chemotherapy and/or radiation therapy with the innate defense system. Bacterial infection of the ulcerative lesions is regarded as a secondary consequence of dysregulated local inflammation triggered by therapy-induced cell death, rather than as the primary cause of the lesions.

We estimate, based upon our review of historic studies and reports, and an interpolation of data on the incidence of oral mucositis, that oral mucositis is a subpopulation of approximately 90,000 patients in the U.S., with a comparable number in Europe. Oral mucositis almost always occurs in patients with head and neck cancer treated with radiation therapy (greater than 80% incidence of severe mucositis) and is common in patients undergoing high dose chemotherapy and hematopoietic cell transplantation, where the incidence and severity of oral mucositis depends greatly on the nature of the conditioning regimen used for myeloablation.

Oral BDP

Oral BDP (beclomethasone 17,21-dipropionate) has been marketed in the U.S. and worldwide since the early 1970s as the active pharmaceutical ingredient in a nasal spray and in a metered-dose inhaler for the treatment of patients with allergic rhinitis and asthma. Oral BDP is specifically formulated for oral administration as a single product consisting of two tablets.

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One tablet is intended to release BDP in the upper sections of the GI tract and the other tablet is intended to release BDP in the lower sections of the GI tract.

Based on its pharmacological characteristics, oral BDP may have utility in treating other conditions of the GI tract having an inflammatory component. We are planning to pursue development programs for the treatment of pediatric Crohn’s disease, acute radiation enteritis and GI acute radiation syndrome pending further grant funding. We are also exploring the possibility of testing oral BDP for local inflammation associated with ulcerative colitis, among other indications.

In July 2019, the European Patent Office issued two patents, both titled “Topically Active Steroids for use in Radiation and Chemotherapeutic Injury”, following the expiration of the objection period. The new patents (#2,373,160 and #2,902,031) claim use of BDP for treatment of damage to the GI tract as a result of acute radiation injury, including total body irradiation in the accidental or biodefense context.

We estimate the potential worldwide market for oral BDP is in excess of $500 million for all applications, including the treatment of pediatric Crohn’s disease. This potential market information is a forward-looking statement, and investors are urged not to place undue reliance on this statement. While we have determined this potential market size based on assumptions that we believe are reasonable, there are a number of factors that could cause our expectations to change or not be realized.

SGX203 – for Treating Pediatric Crohn’s Disease

SGX203 (oral BDP) represents a first-of-its-kind oral, locally acting therapy tailored to treat GI inflammation. Based on its pharmacological characteristics, oral BDP may have utility in treating multiple conditions of the GI tract having an inflammatory component. BDP has been marketed in the U.S. and worldwide since the early 1970s as the API in a nasal spray and in a metered-dose inhaler for the treatment of patients with allergic rhinitis and asthma. SGX203 for the treatment of pediatric Crohn’s disease is specifically formulated as a two tablet delivery system for oral use that allows for administration of immediate and delayed release BDP throughout the small bowel and the colon. The FDA has given SGX203 Orphan Drug designation as well as Fast Track designation for the treatment of pediatric Crohn’s disease. We will pursue a pivotal Phase 3 clinical trial of SGX203 for the treatment of pediatric Crohn’s disease contingent upon additional funding, such as through partnership funding support.

Pediatric Crohn’s Disease

Crohn’s disease causes inflammation of the GI tract. Crohn’s disease can affect any area of the GI tract, from the mouth to the anus, but it most commonly affects the lower part of the small intestine, called the ileum. The swelling caused by the disease extends deep into the lining of the affected organ. The swelling can induce pain and can make the intestines empty frequently, resulting in diarrhea. Because the symptoms of Crohn’s disease are similar to other intestinal disorders, such as irritable bowel syndrome and ulcerative colitis, it can be difficult to diagnose. People of Ashkenazi Jewish heritage have an increased risk of developing Crohn’s disease.

Crohn’s disease can appear at any age, but it is most often diagnosed in adults in their 20s and 30s. However, approximately 30% of people with Crohn’s disease develop symptoms before 20 years of age. We estimate, based upon our review of historic published studies and reports, and an interpolation of data on the incidence of pediatric Crohn’s disease, that pediatric Crohn’s disease is a subpopulation of approximately 80,000 patients in the U.S. with a comparable number in Europe. Crohn’s disease tends to be both severe and extensive in the pediatric population and a relatively high proportion (approximately 40%) of pediatric Crohn’s patients have involvement of their upper GI tract.

Crohn’s disease presents special challenges for children and teens. In addition to bothersome and often painful symptoms, the disease can stunt growth, delay puberty, and weaken bones. Crohn’s disease symptoms may sometimes prevent a child from participating in enjoyable activities. The emotional and psychological issues of living with a chronic disease can be especially difficult for young people.

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Public Health Solutions Overview

ThermoVax® – Thermostability Platform Technology

ThermoVax® is a novel method for thermostabilizing vaccines with a variety of adjuvants, resulting in a single vial which can be reconstituted with water for injection immediately prior to use.

One of the adjuvants utilized in ThermoVax® is aluminum salts (known colloquially as Alum). Alum is the most widely employed adjuvant technology in the vaccine industry.

The value of ThermoVax® lies in its potential ability to eliminate the need for cold chain production, transportation, and storage for Alum-adjuvanted vaccines. This would relieve the high costs of producing and maintaining vaccines under refrigerated conditions. Based on historical reports from the World Health Organization and other scientific reports, we believe that a meaningful proportion of vaccine doses globally are wasted due to excursions from required cold chain temperature ranges. This is due to the fact that many vaccines need to be maintained either between 2 and 8 degrees Celsius (“C”), frozen below -20 degrees C, or frozen below -60 degrees C, and even brief excursions from these temperature ranges usually necessitate the destruction of the product or the initiation of costly stability programs specific for the vaccine lots in question. ThermoVax® has the potential to facilitate easier storage and distribution of strategic national stockpile vaccines for ricin exposure in emergency settings.

ThermoVax® development, specifically in the context of an Alum adjuvant, was supported pursuant to our $9.4 million NIAID grant enabling development of thermo-stable ricin (RiVax®) and anthrax vaccines. Proof-of-concept preclinical studies with ThermoVax® indicate that it is able to produce stable vaccine formulations using adjuvants, protein immunogens, and other components that ordinarily would not withstand long temperature variations exceeding customary refrigerated storage conditions. These studies were conducted with our Alum-adjuvanted ricin toxin vaccine, RiVax® and our Alum-adjuvanted anthrax vaccine. Each vaccine was manufactured under precise lyophilization conditions using excipients that aid in maintaining native protein structure of the key antigen. When RiVax® was kept at 40 degrees C (104 degrees Fahrenheit (“F”)) for up to one year, all of the animals vaccinated with the lyophilized RiVax® vaccine developed potent and high titer neutralizing antibodies. In contrast, animals that were vaccinated with the liquid RiVax® vaccine kept at 40 degrees C did not develop neutralizing antibodies and were not protected against ricin exposure. The ricin A chain is extremely sensitive to temperature and rapidly loses the ability to induce neutralizing antibodies when exposed to temperatures higher than 8 degrees C. When the anthrax vaccine was kept for up to 16 weeks at 70 degrees C, it was able to develop a potent antibody response, unlike the liquid formulation kept at the same temperature. Moreover, we also have demonstrated the compatibility of our thermostabilization technology with other secondary adjuvants such as TLR-4 agonists.

We also entered into a collaboration agreement with Axel Lehrer, PhD of the Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaiʻi at Manoa (“UH Manoa”) and Hawaii Biotech, Inc. (“HBI”) to develop a heat stable subunit Ebola vaccine. Dr. Lehrer, a co-inventor of the Ebola vaccine with HBI, has shown proof of concept efficacy with subunit Ebola vaccines in non-human primates. The most advanced Ebola vaccines involve the use of vesicular stomatitis virus and adenovirus vectors – live, viral vectors which complicate the manufacturing, stability and storage requirements. Dr. Lehrer’s vaccine candidate is based on highly purified recombinant protein antigens, circumventing many of these manufacturing difficulties. Dr. Lehrer and HBI have developed a robust manufacturing process for the required proteins. Application of ThermoVax® may allow for a product that can avoid the need for cold chain distribution and storage, yielding a vaccine ideal for use in both the developed and developing world. This agreement has expired in accordance with its terms.

In December 2010, we executed a worldwide exclusive license agreement with the University of Colorado (“UC”) for certain patents relating to ThermoVax® in all fields of use. In April 2018, the UC delivered a notice of termination of our license agreement based upon our failure to achieve one of the development milestones: initiation of the Phase 1 clinical trial of the heat stabilization technology by March 31, 2018. After negotiating with the UC, we and the UC agreed to extend the termination date to October 31, 2018 in order to allow us time to agree upon a potential agreement that would allow us to keep the rights to, and to continue to develop, the heat stabilization technology or a product candidate containing the heat stabilization technology in our field of use.

During September 2017, we were awarded funding of approximately $700,000 over five years under a NIAID Research Project (R01) grant awarded to UH Manoa for the development of a trivalent thermostabilized filovirus vaccine (including protection against Zaire ebolavirus, Sudan ebolavirus and Marburg Marburgvirus). Previous collaborations demonstrated

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the feasibility of developing a heat stable subunit Ebola vaccine. Under the terms of the subaward, we will continue to support vaccine formulation development with our proprietary vaccine thermostabilization technology, ThermoVax®. Ultimately, the objective is to produce a thermostable trivalent filovirus vaccine for protection against Ebola and related diseases, allowing worldwide distribution without the need for cold storage. Based on current U.S. government needs, efforts have recently been expanded to focus on a monovalent or bivalent vaccine to specifically address Marburg marburgvirus.

In October 2018, in a series of related transactions, (a) we and the UC agreed to terminate the original license agreement, (b) the UC and VitriVax, Inc. (“VitriVax”) executed a worldwide exclusive license agreement for the heat stabilization technology for all fields of use, and (c) we and VitriVax executed a worldwide exclusive sublicense agreement, which was amended and restated in October 2020, for the heat stabilization technology for use in the fields of ricin and Ebola vaccines. We paid a $100,000 sublicense fee on the effective date of the sublicense agreement. Under the amended sublicense agreement to maintain the sublicense we are obliged to pay a minimum annual royalty of $20,000 until first commercial sale of a sublicensed product, upon which point, we shall pay an earned royalty of 2% of net sales subject to a minimum royalty of $50,000 each year. We are also required to pay royalty on any sub-sublicense income based on a declining percentage of all sub-sublicense income calculated within the contractual period until reaching a minimum of 15% after two years. In addition, we are required to pay VitriVax milestone fees of: (a) $25,000 upon initiation of a Phase 2 clinical trial of the sublicensed product, (b) $100,000 upon initiation of a Phase 3 clinical trial of the sublicensed product, (c) $100,000 upon regulatory approval of a sublicensed product, and (d) $1 million upon achieving $10 million in aggregate net sales of a sublicensed product in the U.S. or equivalent. To date none of these milestones have been met.

In March 2020, we entered into a research collaboration with Axel Lehrer, PhD of the Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, UH Manoa to further expand the filovirus collaboration to investigation of potential coronavirus vaccines, including for SARS-CoV-2 (causing COVID-19). This research collaboration will utilize the technology platform developed in the search for filovirus vaccines and will use well-defined surface glycoprotein(s) from one or more coronaviruses, which are expected to be protective for COVID-19.

During April 2020, we obtained an exclusive worldwide license for CiVaxTM, a novel vaccine adjuvant, from BTG Specialty Pharmaceuticals (“BTG”), a division of Boston Scientific Corporation, for the fields of coronavirus infection (including SARS-CoV-2, the cause of COVID-19), and pandemic flu. CiVaxTM is a novel adjuvant, which has been shown to enhance both cell-mediated and antibody-mediated immunity. We and our collaborators, including UH Manoa and Dr. Axel Lehrer, have successfully demonstrated the utility of CiVaxTM in the development of our heat stable filovirus vaccine program, with vaccine candidates against Ebola and Marburg virus disease. Given this previous success, CiVaxTM will potentially be an important component of our vaccine technology platform currently being assessed for use against coronaviruses including SARS-CoV-2, the cause of COVID-19. The license agreement was executed between us and Protherics Medicines Development, one of the companies that make up the BTG specialty pharmaceutical business, which owns the CiVaxTM intellectual property.

In September 2020, the Journal of Pharmaceutical Sciences published a scientific article detailing the thermostabilization of the filovirus GP proteins and key assays describing their stability (available at: https://www.jpharmsci.org/article/S0022-3549(20)30509-8/fulltext).

During October 2020, Frontiers in Immunology published a scientific article describing CiVaxTM, a prototype COVID-19 vaccine, using the novel CoVaccine HTTM adjuvant and demonstrating significant immunogenicity, including strong total and neutralizing antibody responses, with a balanced Th1 response, as well as enhancement of cell mediated immunity. These are all considered to be critical attributes of a potential COVID-19 vaccine. (available at: https://www.frontiersin.org/articles/10.3389/fimmu.2020.599587/full).

In December 2020, NIAID awarded us a Direct to Phase II Small Business Innovation Research (“SBIR”) grant of approximately $1.5 million to support manufacture, formulation (including thermostabilization) and characterization of COVID-19 and Ebola Virus Disease (“EVD”) vaccine candidates in conjunction with the CoVaccine HTTM adjuvant. This award also is supporting immune characterization of this novel, emulsified adjuvant that has unique potency and compatibility with lyophilization strategies to enable thermostabilization of subunit vaccines.

During March 2021, bioRxiv published an accelerated preprint of pre-clinical immunogenicity studies for CiVaxTM, demonstrating rapid-onset, broad-spectrum, neutralizing antibody and cell-mediated immunity is confirmed using full-length Spike protein antigens. The article, titled “Recombinant protein subunit SARS-CoV-2 vaccines formulated with CoVaccine

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HTTM adjuvant induce broad, Th1 biased, humoral and cellular immune responses in mice,” (available at: https://www.biorxiv.org/content/10.1101/2021.03.02.433614v1).

During August 2021, we announced positive data demonstrating the efficacy of multiple filovirus vaccine candidates in non-human primates (“NHP”), including thermostabilized multivalent vaccines in a single vial platform presentation. Collaborators at the University of Hawaiʻi at Mānoa (“UHM”) describe the potent efficacy of vaccine candidates protecting against three life-threatening filoviruses, Zaire ebolavirus, Sudan ebolavirus and Marburg Marburgvirus in an article titled "Recombinant Protein Filovirus Vaccines Protect Cynomolgus Macaques from Ebola, Sudan, and Marburg Viruses", published in Frontiers in Immunology. (available at: https://www.frontiersin.org/articles/10.3389/fimmu.2021.703986/full) These vaccine candidates contain highly purified protein antigens combined with the novel CoVaccine HTTM adjuvant, in both monovalent (single antigen) and bivalent (two antigen) formulations. Most recently, efforts to formulate all three antigens and adjuvant into a thermostable single-vial vaccine platform has also been shown to protect 75% of vaccinated NHPs against subsequent Sudan ebolavirus challenge, with further development to test efficacy against other filovirus infections ongoing.

During August 2021, we announced a publication describing the formulation of single-vial platform presentations of monovalent (single antigen), bivalent (two antigens) and trivalent (three antigens) combinations of filovirus vaccine candidates. In collaboration with UHM and University of Colorado (“UC”) co-authors, the manuscript titled "Single-Vial Filovirus Glycoprotein Vaccines: Biophysical Characteristics and Immunogenicity after Co-lyophilization with Adjuvant", has been published in Vaccine. (available at: https:// www.sciencedirect.com/science/article/pii/S0264410X21010021)

During September 2021 we announced publication of pre-clinical immunogenicity studies for CiVaxTM (heat stable COVID-19 vaccine program) demonstrating durable broad-spectrum neutralizing antibody responses, including against the Beta, Gamma and Delta variants of concern. The article, titled "Protein Vaccine Induces a Durable, More Broadly Neutralizing Antibody Response in Macaques than Natural Infection with SARS-CoV-2 P.1," has been posted as an accelerated preprint on bioRxiv (available at: https://www.biorxiv.org/content/10.1101/2021.09.24.461759v1). The manuscript is part of the ongoing collaboration with Axel Lehrer, PhD, Associate Professor at the Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine (“JABSOM”), UHM. Development continues under a non-dilutive $1.5M grant from the NIAID awarded to Soligenix in December 2020.

In December 2021 we announced 100% protection of NHPs against lethal Sudan ebolavirus challenge using a bivalent, thermostabilized vaccine formulated in a single vial, reconstituted only with water immediately prior to use. This milestone is part of an ongoing collaboration with UHM, demonstrating the successful presentation of one or more antigen(s) within the same formulation while maintaining full potency and thermostability. It further demonstrates the broad applicability of the vaccine platform, and its potential role in the US government's initiative for pandemic preparedness.

RiVax® – Ricin Toxin Vaccine

RiVax® is our proprietary vaccine candidate being developed to protect against exposure to ricin toxin and if approved, would be the first ricin vaccine. The immunogen in RiVax® induces a protective immune response in animal models of ricin exposure and functionally active antibodies in humans. The immunogen consists of a genetically inactivated ricin A chain subunit that is enzymatically inactive and lacks residual toxicity of the holotoxin. RiVax® has demonstrated statistically significant (p < 0.0001) preclinical survival results, providing 100% protection against acute lethality in an aerosol exposure non-human primate model (Roy et al, 2015, Thermostable ricin vaccine protects rhesus macaques against aerosolized ricin: Epitope-specific neutralizing antibodies correlate with protection, PNAS USA 112:3782-3787), and has also been shown to be well tolerated and immunogenic in two Phase 1 clinical trials in healthy volunteers. Results of the first Phase 1 human trial of RiVax® established that the immunogen was safe and induced antibodies that we believe may protect humans from ricin exposure. The antibodies generated from vaccination, concentrated and purified, were capable of conferring immunity passively to recipient animals, indicating that the vaccine was capable of inducing functionally active antibodies in humans. The outcome of this study was published in the Proceedings of the National Academy of Sciences (Vitetta et al., 2006, A Pilot Clinical Trial of a Recombinant Ricin Vaccine in Normal Humans, PNAS, 103:2268-2273). The second trial that was completed in September 2012 and was sponsored by University of Texas Southwestern Medical Center (“UTSW”) evaluated a more potent formulation of RiVax® that contained an Alum-adjuvant. The results of the Phase 1b study indicated that Alum-adjuvanted RiVax® was safe and well tolerated, and induced greater ricin neutralizing antibody levels in humans than adjuvant-free RiVax®. The outcomes of this second study were published in the Clinical and Vaccine Immunology (Vitetta et al., 2012, Recombinant Ricin Vaccine Phase 1b Clinical Trial, Clin. Vaccine Immunol. 10:1697-1699).

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We have adapted the original manufacturing process for the immunogen contained in RiVax® for thermostability and large scale manufacturing and recent studies have confirmed that the thermostabilized RiVax® formulation enhances the stability of the RiVax® antigen, enabling storage for at least 1 year at temperatures up to 40 degrees C (104 degrees F). The program will pursue approval via the FDA “Animal Rule” since it is not possible to test the efficacy of the vaccine in a clinical study which would expose humans to ricin. Uniform, easily measured and species-neutral immune correlates of protection that can be measured in humans and animals, and are indicative of animal survival to subsequent ricin challenge, are central to the application of the “Animal Rule”. Recent work has identified such potential correlates of immune protection in animals and work to qualify and validate these approaches is continuing, with the goal of utilizing these assays in a planned Phase 1/2 clinical trial with the thermostable RiVax® formulation. During September 2018, we published an extended stability study of RiVax®, showing up to 100% protection in mice after 12 months storage at 40 degrees C (104 degrees F) as well as identification of a potential in vitro stability indicating assay, critical to adequately confirming the long-term shelf life of the vaccine. We have entered into a collaboration with IDT Biologika GmbH (“IDT”) to scale-up the formulation/filling process and continue development and validation of analytical methods established at IDT to advance the program. We also initiated a development agreement with Emergent BioSolutions, Inc. to implement a commercially viable, scalable production technology for the RiVax® drug substance protein antigen.

The development of RiVax® has been sponsored through a series of overlapping challenge grants, UC1, and cooperative grants, U01, from the NIH, granted to us and to UTSW where the vaccine originated. The second clinical trial was supported by a grant from the FDA’s Office of Orphan Products to UTSW. To date, we and UTSW have collectively received approximately $25 million in grant funding from the NIH for the development of RiVax®. In September 2014, we entered into a contract with the NIH for the development of RiVax® pursuant to which we have been awarded an additional $21.2 million of funding in the aggregate. The development agreements with Emergent BioSolutions, Inc. and IDT were specifically funded under this NIH contract.

In 2017, NIAID exercised options to fund additional animal efficacy studies and good manufacturing practices compliant RiVax® bulk drug substance and finished drug product manufacturing, which is required for the conduct of future preclinical and clinical safety and efficacy studies. The exercised options provide us with approximately $4.5 million in additional non-dilutive funding, bringing the total amount awarded to date under this contract to $21.2 million, which expired in February 2021. The total award of up to $21.2 million supported the preclinical, manufacturing and clinical development activities necessary to advance heat stable RiVax® with the FDA. In addition to this funding for the development of RiVax®, biomarkers for RiVax® testing have been successfully identified, facilitating potential approval under the FDA Animal Rule.

During December 2019, we initiated a third Phase 1 double-blind, placebo-controlled, randomized study in eight healthy adult volunteer subjects designed to evaluate the safety and immunogenicity of RiVax® utilizing ThermoVax®. During January 2020, we suspended the study after Emergent Manufacturing Operations Baltimore LLC (“EMOB”), the manufacturer of the drug substance, notified us that, after releasing the final drug product to us, EMOB identified that the active drug substance tested outside the established specification parameters. Two subjects had received doses as part of the study before the manufacturer provided this notice. Those two subjects were monitored with no safety issues noted and data was captured in accordance with the study protocol. They did not receive further doses of study drug.

During April 2020, we received notification from NIAID that they would not be exercising the final contract option to support the conduct of a Phase 1/2 clinical study in healthy volunteers. As a result, the total contract award will not exceed $21.2 million. This contract subsequently expired in February 2021.

In connection with failures relating to the manufacture of RiVax® bulk drug substance, on July 1, 2020, we filed a demand for arbitration against Emergent BioSolutions, Inc. (“EBS”), Emergent Product Development Gaithersburg, Inc. (“EPDG”); and EMOB (together with EBS and EPDG, “Emergent”) with the American Arbitration Association in Mercer County, New Jersey. We have alleged that (a) EPDG breached contracts, an express warranty, a warranty of merchantability, and a warranty of fitness for a particular purpose, (b) EMOB breached a contract; (c) EPDG was unjustly enriched; (d) EPDG and EMOB were negligent in the performance of their work; and (e) EBS fraudulently induced us into entering into the contracts with EPDG and EMOB. We are seeking to recover damages in excess of $19 million from Emergent. Emergent has answered the demand for arbitration denying the allegations and asserting affirmative defenses. While we intend to vigorously pursue this arbitration, we cannot offer any assurances as to any result from the arbitration or that we will recover any damages from Emergent. For more details regarding the arbitration against Emergent, see Part I – Item 3. “Legal Proceedings” in this Annual Report.

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In November 2021, we announced publication of pre-clinical immunogenicity studies for RiVax® demonstrating enduring protection for at least 12 months post-vaccination. The article titled “Durable Immunity to Ricin Toxin Elicited by a Thermostable, Lyophilized Subunit Vaccine” has been accepted for publication in the journal mSphere (https://journals.asm.org/dot/10.1128/mSphere.00750-21). These results, coupled with the previous demonstration of efficacy in mice and NHPs as well as long-term thermostability (at least 1 year at 40 degrees C or 104 degrees F), reinforce the practicality of stockpiling and potentially utilizing the RiVax® vaccine in warfighters and civilian first responders without the complexities that arise for vaccines that require stringent cold chain handling.

RiVax® has been granted Orphan Drug designation as well as Fast Track designation by the FDA for the prevention of ricin intoxication. In addition, RiVax® has also been granted Orphan Drug designation in the European Union (“EU”) from the EMA Committee for Orphan Medical Products.

Assuming development efforts are successful for RiVax®, we believe potential government procurement contract(s) could reach as much as $200 million. This potential procurement contract information is a forward-looking statement, and investors are urged not to place undue reliance on this statement. While we have determined this potential procurement contract value based on assumptions that we believe are reasonable, there are a number of factors that could cause our expectations to change or not be realized.

As a new chemical entity, an FDA approved RiVax® vaccine has the potential to qualify for a biodefense Priority Review Voucher (“PRV”). Approved under the 21st Century Cures Act in late 2016, the biodefense PRV is awarded upon approval as a medical countermeasure when the active ingredient(s) have not been otherwise approved for use in any context. PRVs are transferable and can be sold, with sales in recent years of approximately $100 million. When redeemed, PRVs entitle the user to an accelerated review period of nine months, saving a median of seven months review time as calculated in 2009. However, FDA must be advised 90 days in advance of the use of the PRV and the use of a PRV is associated with an additional user fee ($2.2 million for fiscal year 2020).

Ricin Toxin

Ricin toxin can be cheaply and easily produced, is stable over long periods of time, is toxic by several routes of exposure and thus has the potential to be used as a biological weapon against military and/or civilian targets. As a bioterrorism agent, ricin could be disseminated as an aerosol, by injection, or as a food supply contaminant. The potential use of ricin toxin as a biological weapon of mass destruction has been highlighted in a Federal Bureau of Investigation Bioterror report released in November 2007 titled Terrorism 2002-2005, which states that “Ricin and the bacterial agent anthrax are emerging as the most prevalent agents involved in WMD investigations” (http://www.fbi.gov/stats-services/publications/terrorism-2002-2005/terror02_05.pdf). In recent years, Al Qaeda in the Arabian Peninsula has threatened the use of ricin toxin to poison food and water supplies and in connection with explosive devices. Domestically, the threat from ricin remains a concern for security agencies. In April 2013, letters addressed to the U.S. President, a Senator and a judge tested positive for ricin. As recently as September 2020, ricin-laced letters addressed to the White House and others addressed to Texas law enforcement agencies were intercepted before delivery raising fresh concerns about the deadly toxin.

The Centers for Disease Control and Prevention has classified ricin toxin as a Category B biological agent. Ricin works by first binding to glycoproteins found on the exterior of a cell, and then entering the cell and inhibiting protein synthesis leading to cell death. Once exposed to ricin toxin, there is no effective therapy available to reverse the course of the toxin. The recent ricin threat to government officials has heightened the awareness of this toxic threat. Currently, there is no FDA approved vaccine to protect against the possibility of ricin toxin being used in a terrorist attack, or its use as a weapon on the battlefield nor is there a known antidote for ricin toxin exposure.

SGX943 – for Treating Emerging and/or Antibiotic-Resistant Infectious Diseases

SGX943 is an IDR, containing the same active ingredient as SGX942. Dusquetide is a fully synthetic, 5-amino acid peptide with high aqueous solubility and stability. Extensive in vivo preclinical studies have demonstrated enhanced clearance of bacterial infection with SGX943 administration. SGX943 has shown efficacy against both Gram-negative and Gram-positive bacterial infections in preclinical models, independent of whether the bacteria is antibiotic-resistant or antibiotic-sensitive.

The innate immune system is responsible for rapid and non-specific responses to combat bacterial infection. Augmenting these responses represents an alternative approach to treating bacterial infections. In animal models, IDRs are efficacious

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against both antibiotic-sensitive and antibiotic-resistant infections, both Gram-positive and Gram-negative bacteria, and are active irrespective of whether the bacteria occupy a primarily extracellular or intracellular niche. IDRs are also effective as stand-alone agents or in conjunction with antibiotics. An IDR for the treatment of serious bacterial infections encompasses a number of clinical advantages including:

● Treatment when antibiotics are contraindicated, such as:

o in at-risk populations prior to infection.

Importantly, systemic inflammation and multi-organ failure is the ultimate common outcome of not only emerging and/or antibiotic-resistant infectious diseases, but also of most biothreat agents (e.g., Burkholderia pseudomallei), indicating that dusquetide would be applicable not only to antibiotic-resistant infection, but also to biothreat agents, especially where the pathogen is not known and/or has been engineered for enhanced antibiotic resistance.

In May 2019, we were awarded a DTRA subcontract of approximately $600,000 over three years to participate in a biodefense contract for the development of medical countermeasures against bacterial threat agents. As of December 31, 2021, there was negligible revenue earned or expense incurred related to the DTRA subcontract.

The Drug Approval Process

The FDA and comparable regulatory agencies in state, local and foreign jurisdictions impose substantial requirements on the clinical development, manufacture and marketing of new drug and biologic products. The FDA, through regulations that implement the Federal Food, Drug, and Cosmetic Act, as amended (“FDCA”), and other laws and comparable regulations for other agencies, regulate research and development activities and the testing, manufacture, labeling, storage, shipping, approval, recordkeeping, advertising, promotion, sale, export, import and distribution of such products. The regulatory approval process is generally lengthy, expensive and uncertain. Failure to comply with applicable FDA and other regulatory requirements can result in sanctions being imposed on us or the manufacturers of our products, including holds on clinical research, civil or criminal fines or other penalties, product recalls, or seizures, or total or partial suspension of production or injunctions, refusals to permit products to be imported into or exported out of the U.S., refusals of the FDA to grant approval of drugs or to allow us to enter into government supply contracts, withdrawals of previously approved marketing applications and criminal prosecutions.

Before human clinical testing in the U.S. of a new drug compound or biological product can commence, an Investigational New Drug (“IND”), application is required to be submitted to the FDA. The IND application includes results of pre-clinical animal studies evaluating the safety and efficacy of the drug and a detailed description of the clinical investigations to be undertaken.

Clinical trials are normally done in three phases, although the phases may overlap. Phase 1 trials are smaller trials concerned primarily with metabolism and pharmacologic actions of the drug and with the safety of the product. Phase 2 trials are designed primarily to demonstrate effectiveness and safety in treating the disease or condition for which the

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product is indicated. These trials typically explore various doses and regimens. Phase 3 trials are expanded clinical trials intended to gather additional information on safety and effectiveness needed to clarify the product’s benefit-risk relationship and generate information for proper labeling of the drug, among other things. The FDA receives reports on the progress of each phase of clinical testing and may require the modification, suspension or termination of clinical trials if an unwarranted risk is presented to patients. When data is required from long-term use of a drug following its approval and initial marketing, the FDA can require Phase 4, or post-marketing, studies to be conducted.

With certain exceptions, once successful clinical testing is completed, the sponsor can submit an NDA, for approval of a drug, or a Biologic License Application (“BLA”), for biologics such as vaccines, which will be reviewed, and if successful, approved by the FDA, allowing the product to be marketed. The process of completing clinical trials for a new drug is likely to take a number of years and require the expenditure of substantial resources. Furthermore, the FDA or any foreign health authority may not grant an approval on a timely basis, if at all. The FDA may deny the approval of an NDA or BLA, in its sole discretion, if it determines that its regulatory criteria have not been satisfied or may require additional testing or information. Among the conditions for marketing approval is the requirement that the prospective manufacturer’s quality control and manufacturing procedures conform to good manufacturing practice regulations. In complying with standards contained in these regulations, manufacturers must continue to expend time, money and effort in the area of production, quality control and quality assurance to ensure full technical compliance. Manufacturing facilities, both foreign and domestic, also are subject to inspections by, or under the authority of, the FDA and by other federal, state, local or foreign agencies.

Even after initial FDA or foreign health authority approval has been obtained, further studies, including Phase 4 post-marketing studies, may be required to provide additional data on safety and will be required to gain approval for the marketing of a product as a treatment for clinical indications other than those for which the product was initially tested. For certain drugs intended to treat serious, life-threatening conditions that show great promise in earlier testing, the FDA can also grant conditional approval. However, drug developers are required to study the drug further and verify clinical benefit as part of the conditional approval provision, and the FDA can revoke approval if later testing does not reproduce previous findings. The FDA may also condition approval of a product on the sponsor agreeing to certain mitigation strategies that can limit the unfettered marketing of a drug. Also, the FDA or foreign regulatory authority will require post-marketing reporting to monitor the side effects of the drug. Results of post-marketing programs may limit or expand the further marketing of the product. Further, if there are any modifications to the drug, including any change in indication, manufacturing process, labeling or manufacturing facility, an application seeking approval of such changes will likely be required to be submitted to the FDA or foreign regulatory authority.

In the U.S., the FDCA, the Public Health Service Act, the Federal Trade Commission Act, and other federal and state statutes and regulations govern, or influence the research, testing, manufacture, safety, labeling, storage, record keeping, approval, advertising and promotion of drug, biological, medical device and food products. Noncompliance with applicable requirements can result in, among other things, fines, recall or seizure of products, refusal to permit products to be imported into the U.S., refusal of the government to approve product approval applications or to allow us to enter into government supply contracts, withdrawal of previously approved applications and criminal prosecution. The FDA may also assess civil penalties for violations of the FDCA involving medical devices.

For biodefense development, such as with RiVax®, the FDA has instituted policies that are expected to result in shorter pathways to market. This potentially includes approval for commercial use utilizing the results of animal efficacy trials, rather than efficacy trials in humans. However, we will still have to establish that the vaccine and countermeasures it is developing are safe in humans at doses that are correlated with the beneficial effect in animals. Such clinical trials will also have to be completed in distinct populations that are subject to the countermeasures; for instance, the very young and the very old, and in pregnant women, if the countermeasure is to be licensed for civilian use. Other agencies will have an influence over the benefit-risk scenarios for deploying the countermeasures and in establishing the number of doses utilized in the Strategic National Stockpile. We may not be able to sufficiently demonstrate the animal correlation to the satisfaction of the FDA, as these correlates are difficult to establish and are often unclear. Invocation of the animal rule may raise issues of confidence in the model systems even if the models have been validated. For many of the biological threats, the animal models are not available and we may have to develop the animal models, a time-consuming research effort. There are few historical precedents, or recent precedents, for the development of new countermeasure for bioterrorism agents. Despite the animal rule, the FDA may require large clinical trials to establish safety and immunogenicity before licensure and it may require safety and immunogenicity trials in additional populations. Approval of biodefense products may be subject to post-marketing studies, and could be restricted in use in only certain populations.

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Vaccines are approved under the BLA process that exists under the Public Health Service Act. In addition to the greater technical challenges associated with developing biologics, the potential for generic competition is lower for a BLA product than a small molecule product subject to an NDA under the Federal Food, Drug and Cosmetic Act. Under the Patient Protection and Affordable Care Act enacted in 2010, a “generic” version of a biologic is known as a biosimilar and the barriers to entry – whether legal, scientific, or logistical – for a biosimilar version of a biologic approved under a BLA are higher.

Orphan Drug Designation

Under the Orphan Drug Act, the FDA may grant orphan drug designation to drugs or biologics intended to treat a rare disease or condition – generally a disease or condition that affects fewer than 200,000 individuals in the U.S. Orphan drug designation must be requested before submitting an NDA or BLA. After the FDA grants orphan drug designation, the generic identity of the drug or biologic and its potential orphan use are disclosed publicly by the FDA. Orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. The first NDA or BLA applicant to receive FDA approval for a particular active ingredient to treat a particular disease with FDA orphan drug designation is entitled to a seven-year exclusive marketing period in the U.S. for that product, for that indication. During the seven-year exclusivity period, the FDA may not approve any other applications to market the same drug or biologic for the same disease, except in limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity. Orphan drug exclusivity does not prevent the FDA from approving a different drug or biologic for the same disease or condition, or the same drug or biologic for a different disease or condition. Among the other benefits of orphan drug designation are tax credits for certain research and a waiver of the NDA or BLA application user fee.

Fast Track Designation and Accelerated Approval

The FDA is required to facilitate the development, and expedite the review, of drugs or biologics that are intended for the treatment of a serious or life-threatening disease or condition for which there is no effective treatment and which demonstrate the potential to address unmet medical needs for the condition. Under the fast track program, the sponsor of a new drug or biologic candidate may request that the FDA designate the candidate for a specific indication as a fast track drug or biologic concurrent with, or after, the filing of the IND for the candidate. The FDA must determine if the drug or biologic candidate qualifies for fast track designation within 60 days of receipt of the sponsor’s request. Unique to a fast track product, the FDA may initiate review of sections of a fast track product’s NDA or BLA before the application is complete. This rolling review is available if the applicant provides, and the FDA approves, a schedule for the submission of the remaining information and the applicant pays applicable user fees. However, the FDA’s time period goal for reviewing an application does not begin until the last section of the NDA or BLA is submitted. Additionally, 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.

Any product submitted to the FDA for marketing, including under a fast track program, may be eligible for other types of FDA programs intended to expedite development and review, such as accelerated approval. Drug or biological products studied for their safety and effectiveness in treating serious or life-threatening illnesses and that provide meaningful therapeutic benefit over existing treatments may receive accelerated approval, which means the FDA may approve the product based upon a surrogate endpoint that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality, 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.

In clinical trials, a surrogate endpoint is a measurement of laboratory or clinical signs of a disease or condition that substitutes for a direct measurement of how a patient feels, functions, or survives. Surrogate endpoints can often be measured more easily or more rapidly than clinical endpoints. A drug or biologic 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, will allow the FDA to withdraw the drug or biologic 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.

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Pediatric Information

Under the Pediatric Research Equity Act (“PREA”), NDAs or BLAs or supplements to NDAs or BLAs must contain data to assess the safety and effectiveness 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 drug is safe and effective. The FDA may grant full or partial waivers, or deferrals, for submission of data. Unless otherwise required by regulation, PREA does not apply to any drug for an indication for which orphan designation has been granted.

Paediatric Investigation Plan

As part of the regulatory process for the registration of new medicines with the EMA and the MHRA, pharmaceutical companies are required to provide a PIP outlining the Company’s strategy for investigation of the new medicinal products in the paediatric population. In some instances, a waiver negating the need for a PIP for certain conditions may be granted by the EMA or MHRA when development of a medicine for use in children is not feasible or appropriate.

Innovative Licensing and Access Pathway

The ILAP was launched in the UK at the start of 2021 to accelerate the development and access to promising medicines, thereby facilitating patient access to new medicines. The pathway, part of the UK’s plan to attract life sciences development in the post-Brexit era, features enhanced input and interactions with the MHRA and other stakeholders including the NICE, and the SMC. The decision to award the Innovation Passport is made by an ILAP Steering Group, which is comprised of representatives from MHRA, NICE, and SMC. The Innovation Passport designation is the first step in the ILAP process and triggers the MHRA and its partner agencies to create a target development profile to chart out a roadmap for regulatory and development milestones with the goal of early patient access in the UK. Other benefits of ILAP include a 150-day accelerated assessment, rolling review and a continuous benefit risk assessment.

Early Access to Medicines Scheme

Launched in April 2014 in the United Kingdom by the MHRA, the Early Access to Medicines Scheme (“EAMS”) offers severely ill patients with life-threatening and seriously debilitating conditions the lifeline of trying ground-breaking new medicines earlier than they would normally be accessible. PIM designation is the first phase of EAMS and is awarded following an assessment of early nonclinical and clinical data by the MHRA. The criteria product candidates must meet to obtain PIM designation are:

False Claims Laws

The federal False Claims Act prohibits, among other things, any person or entity from knowingly presenting, or causing to be presented, a false claim for payment to, or approval by, the federal government or knowingly making, using, or causing to be made or used a false record or statement material to a false or fraudulent claim to the federal government. As a result of a modification made by the Fraud Enforcement and Recovery Act of 2009, a claim includes “any request or demand” for money or property presented to the U.S. government.

Anti-Kickback Laws

The federal Anti-Kickback Statute prohibits, among other things, any person or entity, from knowingly and willfully offering, paying, soliciting or receiving any remuneration, directly or indirectly, overtly or covertly, in cash or in kind, to induce or in

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return for purchasing, leasing, ordering or arranging for the purchase, lease or order of any item or service reimbursable under Medicare, Medicaid or other federal healthcare programs. The term remuneration has been interpreted broadly to include anything of value. The Anti-Kickback Statute has been interpreted to apply to arrangements between pharmaceutical manufacturers on one hand and prescribers, purchasers, and formulary managers on the other.

United States Healthcare Reform

Federal Physician Payments Sunshine Act and its implementing regulations require that certain manufacturers of drugs, devices, biological and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program (with certain exceptions) to report information related to certain payments or other transfers of value made or distributed to physicians and teaching hospitals, or to entities or individuals at the request of, or designated on behalf of, the physicians and teaching hospitals and to report annually certain ownership and investment interests held by physicians and their immediate family members.

In addition, we may be subject to data privacy and security regulation by both the federal government and the states in which we conduct our business. The Health Insurance Portability and Accountability Act (“HIPAA”), as amended by the Health Information Technology for Economic and Clinical Health Act (“HITECH”), and its implementing regulations, imposes certain requirements relating to the privacy, security and transmission of individually identifiable health information. Among other things, HITECH makes HIPAA’s privacy and security standards directly applicable to “business associates” – independent contractors or agents of covered entities that receive or obtain protected health information in connection with providing a service on behalf of a covered entity. HITECH also created four new tiers of civil monetary penalties, amended HIPAA to make civil and criminal penalties directly applicable to business associates and possibly other persons, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorneys’ fees and costs associated with pursuing federal civil actions. In addition, state laws govern the privacy and security of health information in certain circumstances, many of which differ from each other in significant ways and may not have the same effect, thus complicating compliance efforts.

Third-Party Suppliers and Manufacturers

Drug substance and drug product manufacturing is outsourced to qualified suppliers. We do not have manufacturing capabilities/infrastructure and do not intend to develop the capacity to manufacture drug products substances. We have agreements with third-party manufacturers to supply bulk drug substances for our product candidates and with third parties to formulate, package and distribute our product candidates. Our employees include professionals with expertise in pharmaceutical manufacturing development, quality assurance and third party supplier management who oversee work conducted by third-party companies. We believe that we have on hand or can easily obtain sufficient amounts of product candidates to complete our currently contemplated clinical trials. All of the drug substances used in our product candidates currently are manufactured by single suppliers. While we have not experienced any supply disruptions, the number of manufacturers of the drug substances is limited. In the event it is necessary or advisable to acquire supplies from alternative suppliers, assuming commercially reasonable terms could be reached, the challenge would be the efficient transfer of technology and know-how from current manufactures to the new supplier. Formulation and distribution of our finished product candidates also currently are conducted by single suppliers but we believe that alternative sources for these services are readily available on commercially reasonable terms, subject to the efficient transfer of technology and know-how from current suppliers to the new supplier.

All of the current agreements for the supply of bulk drug substances for our product candidates and for the formulation or distribution of our product candidates relate solely to the development (including preclinical and clinical) of our product candidates. Under these contracts, our product candidates are manufactured upon our order of a specific quantity. In the event that we obtain marketing approval for a product candidate, we will qualify secondary suppliers for all key manufacturing activities supporting the marketing application.

Marketing and Collaboration

We do not currently have any sales and marketing capability, other than to potentially market our biodefense vaccine products directly to government agencies. With respect to other commercialization efforts, we currently intend to seek distribution and other collaboration arrangements for the sales and marketing of any product candidate that is approved, while also evaluating the potential to commercialize on our own in orphan disease indications. From time to time, we have had and are having strategic discussions with potential collaboration partners for our biodefense vaccine product

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candidates, although no assurance can be given that we will be able to enter into one or more collaboration agreements for our product candidate on acceptable terms, if at all. We believe that both military and civilian health authorities of the U.S. and other countries will increase their stockpiling of therapeutics and vaccines to treat and prevent diseases and conditions that could ensue following a bioterrorism attack.

On December 20, 2012, we re-acquired the North American and European commercial rights to oral BDP through an amendment of our collaboration and supply agreement with Sigma-Tau Pharmaceuticals, Inc., which is now known as Leadiant Biosciences, Inc. (“Leadiant”). The amendment requires us to make certain approval and commercialization milestone payments to Leadiant which could reach up to $6 million. In addition, we have agreed to pay Leadiant: (a) a royalty amount equal to 3% of all net sales of oral BDP made directly by us, and any third-party partner and/or their respective affiliates in the U.S., Canada, Mexico and in each country in the European Territory for the later to occur of: (i) a period of ten years from the first commercial sale of oral BDP in each country, or (ii) the expiration of our patents and patent applications relating to oral BDP in such country (the “Payment Period”); and (b) 15% of all up-front payments, milestone payments and any other consideration (exclusive of equity payments) received by us and/or a potential partner from us and/or potential partner’s licensees, distributors and agents for oral BDP in each relevant country in the territory, which amount will be paid on a product-by-product and a country-by-country basis for the Payment Period.

On August 25, 2013, we entered into an agreement with SciClone, pursuant to which SciClone provided us with access to its oral mucositis clinical and regulatory data library in exchange for exclusive commercialization rights for SGX942 in the People’s Republic of China, including Hong Kong and Macau, subject to the negotiation of economic terms. SciClone’s data library was generated from two sequential Phase 2 clinical studies conducted in 2010 and 2012 evaluating SciClone’s compound, SCV-07, for the treatment of oral mucositis caused by chemoradiation therapy in head and neck cancer patients, before SciClone terminated its program. By analyzing data available from the placebo subjects in the SciClone trials, we acquired valuable insight into disease progression, along with quantitative understanding of its incidence and severity in the head and neck cancer patient population. This information assisted us with the design of the SGX942 Phase 2 clinical trial, in which positive preliminary results were announced in December 2015.

On September 9, 2016, we and SciClone entered into an exclusive license agreement, pursuant to which we granted rights to SciClone to develop, promote, market, distribute and sell SGX942 in the People’s Republic of China, including Hong Kong and Macau, as well as Taiwan, South Korea and Vietnam. Under the terms of the license agreement, SciClone will be responsible for all aspects of development, product registration and commercialization in the territory, having access to data generated by us. In exchange for exclusive rights, SciClone will pay us royalties on net sales, and we will supply commercial drug product to SciClone on a cost-plus basis, while maintaining worldwide manufacturing rights. We also entered into a common stock purchase agreement with SciClone pursuant to which we sold 352,942 shares of our common stock to SciClone for approximately $8.50 per share, for an aggregate price of $3,000,000.

Competition

Our competitors are pharmaceutical and biotechnology companies, most of whom have considerably greater financial, technical, and marketing resources than we do. Universities and other research institutions, including the U.S. Army Medical Research Institute of Infectious Diseases, also compete in the development of treatment technologies, and we face competition from other companies to acquire rights to those technologies.

HyBryteTM Competition

The FDA has approved several treatments for later stages (IIB-IV) of CTCL and/or in conditions that are unresponsive to prior treatment. Three are targeted therapies (Targretin®-caps, Ontak® and Adcetris®), two are histone deacetylases inhibitors (Zolina® and Istodax®) and the remaining two are topical therapies (Valchor® and Targretin®-gel). There are currently no FDA approved therapies for the treatment of front-line, early stage (I-IIA) CTCL; however certain topical chemotherapies and topical, radiation, photodynamic and other therapies which are approved for indications other than CTCL are prescribed off-label for the treatment of early stage CTCL. These include narrow-band ultraviolet B (NB-UVB) light therapy and psoralen combined with ultraviolet A UVA light therapy (“PUVA”); however, PUVA treatments are usually limited to three times per week and 200 times in total due to the potentially carcinogenic side effect, while NB UVB is known to be effective against patches but less so against plaque lesions, common in early stage CTCL. There are other drugs currently in development that may have the potential to be used in early stage (I-IIA) CTCL, including, one PDT (Silicon

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Phthalocyanine 4) in Phase 1 and one topical therapy (naloxone lotion for treatment of pruritus only) in Phase 3. Other treatments for later stage disease are not considered direct competitors.

SGX94/942 Competition

Because SGX94 (dusquetide) uses a novel mechanism of action in combating bacterial infections, there are no direct competitors at this time. Bacterial infections are routinely treated with antibiotics and SGX94 treatment is anticipated to be utilized primarily where antibiotics are insufficient (e.g., due to antibiotic resistance) or contra-indicated (e.g., in situations where the development of antibiotic resistance is a significant concern). Many groups are working on the antibiotic resistance problem and research into the innate immune system is intensifying, making emerging competition likely (from companies such as Celtaxsys Inc., Innaxon Therapeutics and Innate Pharma SA).

There is currently one drug approved for the treatment of oral mucositis in hematological cancer (palifermin). There are currently no approved drugs for treatment of oral mucositis in cancers with solid tumors (e.g., head and neck cancer). There are several drugs in clinical development for oral mucositis – three in Phase 3 (brilacidin by Innovation Pharmaceuticals, Inc., GC4419 by Galera Therapeutics, Inc., and a mucobuccal tablet by Monopar Therapeutics LLC). There are various natural products in small and/or open label studies (including sage, turmeric, honey and olive oil). In addition, there are medical devices approved for the treatment of oral mucositis including MuGard®, GelClair®, Episil®, and Caphosol®. These devices attempt to create a protective barrier around the oral ulceration with no biologic activity in treating the underlying disease.

Oral BDP Competition

There are a number of approved treatments for Crohn’s disease and additional compounds are in late-stage development.

Remicade® (infliximab) and Humira® (adalimumab) are currently approved for the treatment of pediatric Crohn’s disease; however, both carry significant Black Box warnings in their labeling for increased risk of serious infection and malignancy, and therefore are approved for treatment of moderate to severe patients. Entocort® (enteric-coated budesonide) is currently approved for the treatment of mild to moderate active Crohn’s disease involving the lower GI tract (ileum and/or the ascending colon) in patients eight years of age and older who weigh more than 25 kilograms. There is one other marketed biologic, Tysabri® (natalizumab), in a Phase 2 study for pediatric Crohn’s.

ThermoVax® Competition

Multiple groups and companies are working to address the unmet need of vaccine thermostability using a variety of technologies. In addition, other organizations, such as the Bill and Melinda Gates Foundation and PATH, have programs designed to advance technologies to address this need.

Several stabilization technologies currently being developed involve mixing vaccine antigen +/- adjuvant with various proprietary excipients or co-factors that either serve to stabilize the vaccine or biological product in a liquid or dried (lyophilized) form. Examples of these approaches include the use of various plant-derived sugars and macromolecules being developed by companies such as iosBio. Variation Biotechnologies, Inc. (“VBI”) is developing a lipid system (resembling liposomes) to stabilize viral antigens, including virus-like particles (“VLPs”), and for potential application to a conventional influenza vaccine among others.

Additionally, companies like Altimmune, Inc., and Panacea Biotec Ltd., and Compass Biotech Inc. are developing proprietary vaccines with the application of some form of stabilization technology.

Public Health Solutions Competition

We face competition in the area of biodefense product development from various public and private companies, universities and governmental agencies, such as the U.S. Army, some of whom may have their own proprietary technologies which may directly compete with our technologies.

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The U.S. Army Medical Research Institute of Infectious Diseases, the DoD’s lead laboratory for medical research to counter biological threats is also developing a ricin vaccine candidate, RVEcTM. RVEcTM has been shown to be fully protective in mice exposed to lethal doses of ricin toxin by the aerosol route. Further studies, in both rabbits and nonhuman primates, were conducted to evaluate RVEcTM’s safety as well as its immunogenicity, with positive results observed. No further data has been released in recent years. A monoclonal antibody is also being developed by Mapp Biopharmaceutical Inc. as a ricin therapeutic, with administration 4 hours after exposure demonstrating efficacy while administration 12 hours after ricin exposure was not protective in animal models.

Patents and Other Proprietary Rights

Our goal is to obtain, maintain and enforce patent protection for our products, formulations, processes, methods and other proprietary technologies, preserve our trade secrets, and operate without infringing on the proprietary rights of other parties, both in the U.S. and in other countries. Our policy is to actively seek to obtain, where appropriate, the broadest intellectual property protection possible for our product candidates, proprietary information and proprietary technology through a combination of contractual arrangements and patents, both in the U.S. and elsewhere in the world.

We also depend upon the skills, knowledge and experience of our scientific and technical personnel, as well as that of our advisors, consultants and other contractors, none of which is patentable. To help protect our proprietary knowledge and experience that is not patentable, and for inventions for which patents may be difficult to enforce, we rely on trade secret protection and confidentiality agreements to protect our interests. To this end, we require all employees, consultants, advisors and other contractors to enter into confidentiality agreements, which prohibit the disclosure of confidential information and, where applicable, require disclosure and assignment to us of the ideas, developments, discoveries and inventions important to our business.

In 2014, we acquired a novel PDT that utilizes safe visible light for activation, which we refer to as HyBryteTM. The active ingredient in HyBryteTM is synthetic hypericin, a photosensitizer which is topically applied to skin lesions and then activated by fluorescent light 16 to 24 hours later. As part of the acquisition, we acquired a license agreement relating to the use of photo-activated hypericin, composition of matter patent for HyBryteTM (U.S. patent 8,629,302) and additional issued and pending applications, both in the U.S. and abroad. U.S. patent 8,629,302 is expected to expire in September 2030. In August 2018, we were granted a U.S. patent (No. 10,053,513) titled “Systems and Methods for Producing Synthetic Hypericin”. This newly issued patent, expected to expire in 2036, broadens the production around synthetic hypericin. Our proprietary formulation of synthetic hypericin also has been granted a European patent for the treatment of psoriasis, EP 2571507, and complements the method of treatment claims covered by the previously issued U.S. patent 6001882, Photoactivated hypericin and the use thereof. Further, on January 7, 2020, Soligenix was also granted a U.S. patent (No. 10,526,268) titled “Systems and Methods for Producing Synthetic Hypericin”, which further expanded protection for the composition of purified synthetic hypericin. This patent is also expected to expire in 2036. Patent protection is also pursued worldwide with similar patents and expiry dates.

In addition to issued and pending patents, we also have “Orphan Drug” designations for HyBryteTM in the U.S. and the EU for CTCL, SGX203 in the U.S. for pediatric Crohn’s disease, as well as for RiVax® in the U.S. and EU. Our Orphan Drug designations provide for seven years of post-approval marketing exclusivity in the U.S. and ten years exclusivity in Europe. We have pending patent applications for this indication that, if granted, may extend our anticipated marketing exclusivity beyond the U.S. seven year or EU ten year post-approval exclusivity provided by Orphan Drug legislation.

In 2013, we expanded our patent portfolio to include innate defense regulation through the acquisition of the novel drug technology, known as SGX94. By binding to the pivotal regulatory protein p62, also known as sequestosome-1, SGX94 regulates the innate immune system to reduce inflammation, eliminate infection and enhance healing. As part of the acquisition, we acquired all rights, including composition of matter patents for SGX94 as well as other analogs and crystal structures of SGX94 with its protein target p62, including U.S. patent 8,124,721 (expiring 2028), 9,416,157 (expiring 2028) and 8,791,061 (expiring 2029), both in the U.S. and abroad. SGX94 was developed pursuant to discoveries made by Professors B. Brett Finlay and Robert Hancock of University of British Columbia (“UBC”). Soligenix also has rights to the background technology patents (U.S. patent numbers 7,507,787 [expiring 2024] and 7,687,454 [expiring 2026]). The U.S. Patent Office has also granted patents titled “Novel Peptides and Analogs for Use in the Treatment of Oral Mucositis”. The issued patents (U.S. patent numbers 9,850.279 and 10,253,068, both expiring in 2034) claim therapeutic use of dusquetide and related IDR analogs, and adds to composition of matter claims for dusquetide and related analogs that have been granted in the U.S. and worldwide.

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We have issued U.S. patent 8,263,582 that cover the use of oral BDP for treating inflammatory disorders of the gastrointestinal tract, which patent expired on March 15, 2022. We also have European patent EP 1392321 claiming the use of topically active corticosteroids in orally administered dosage forms that act concurrently to treat inflammation in the upper and lower gastrointestinal tract, as well as European patent EP 2242477 claiming the use of orally ingested BDP for treatment of interstitial lung disease. European patents EP 1392321 and EP 2242477 expired in March 2022 and expire on January 2029, respectively.

The subject of U.S. patent application number 12/633,631 filed December 8, 2009 and continued into patent application 15/495,798 filed April 24, 2017 and corresponding European patent application number 09836727.9, which was granted as patent 2373160 in October 2017 and pursued in multiple European countries, is the use of topically active BDP in radiation and chemotherapeutics injury. Additionally, we have numerous patent filings currently issued or pending in foreign jurisdictions covering this subject matter, including Australia, Canada, China, Hong Kong, Israel, Japan, South Korea and New Zealand.

ThermoVax® is the subject of U.S. patents 8,444,991 (expiring February 2030) and 8,808,710 (expiring March 2028) both issued on May 21, 2013 titled “Method of Preparing an Immunologically-Active Adjuvant-Bound Dried Vaccine Composition” and licensed to us by VitriVax, Inc. ThermoVax® is also U.S. patent application number 15/694.023 filed September 17, 2017 titled “Thermostable Vaccine Compositions and Methods of Preparing Same” and jointly invented by the UC and the Company. The patent application and the corresponding foreign filings are pending or granted and they address the use of adjuvants in conjunction with vaccines that are formulated to resist thermal inactivation. The license agreement covers thermostable alum-adjuvanted vaccines for ricin toxin and Ebola virus. An additional patent, covering vaccine combinations such as ricin toxin and anthrax, was filed in 2015 and granted on May 21, 2019 in the U.S. (No. 10,293,041, titled “Multivalent Stable Vaccine Composition and Methods of Making Same”) and is expected to expire in 2035. Patent protection is also pursued worldwide with similar patents and expiry dates

Additional vaccine thermostabilization patents specific for anti-viral vaccines, including filovirus and coronavirus have been filed but are not yet granted. If granted, expiry dates would range from 2040 to 2041. Patent protection is also pursued worldwide with similar patents and expiry dates.

HyBryteTM License Agreement

In September 2014, we acquired a worldwide exclusive license agreement with New York University and Yeda Research and Development Company Ltd. for the rights to a novel PDT that utilizes safe visible light for activation, which we refer to as HyBryteTM. To maintain this license, we are obligated to pay $25,000 in annual license fees. In addition, we will pay the licensors: (a) a royalty amount equal to 3% of all net sales of HyBryteTM made directly by us and/or any affiliates; (b) a royalty amount equal to 2.5% of all net sales of HyBryteTM made by our sublicensees, subject to stated maximums and (c) 20% of all payments, not based on net sales, received by us from our sublicensees. This license may be terminated by either party upon notice of a material breach by the other party that is not cured within the applicable cure period. The exclusive license includes rights to several issued U.S. patents, including U.S. patent numbers 6,867,235 and 7,122,518, among other domestic and foreign patent applications. U.S. Patent numbers 6,867,235 and 7,122,518 expired in January 2020 and is expected to expire in November 2023, respectively.

We acquired the license agreement for HyBryteTM and related intangible assets, including U.S. patent 8,629,302, properties and rights pursuant to an asset purchase agreement with Hy Biopharma Inc. (“Hy Biopharma”). As consideration for the assets acquired, we initially paid $275,000 in cash and issued 184,912 shares of common stock with a market value of $3,750,000, and in March 2020 we issued 1,956,182 shares of common stock at a value of $5,000,000 (based upon an effective per share price of $2.56) as a result of HyBryteTM demonstrating statistical significant treatment response in the Phase 3 clinical trial. Provided the final success-orientated milestone is attained, we will be required to make a payment of up to $5.0 million, if and when achieved, payable in our common stock.

SGX94 License Agreements

On December 18, 2012, we announced the acquisition of a first in class drug technology, known as SGX94 (dusquetide), representing a novel approach to modulation of the innate immune system. SGX94 is an IDR that regulates the innate immune system to reduce inflammation, eliminate infection and enhance tissue healing by binding to the pivotal regulatory protein p62, also known as sequestosome-1. As part of the acquisition, we acquired all rights, including composition of

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matter patents, preclinical and Phase 1 clinical study datasets for SGX94. We also assumed a license agreement with UBC to advance the research and development of the SGX94 technology. The license agreement with UBC provides us with exclusive worldwide rights to manufacture, distribute, market sell and/or license or sublicense products derived or developed from this technology. Under the license agreement we are obligated to pay UBC (i) an annual license maintenance fee of CAN $1,000, and (ii) milestone payments which could reach up to CAN $1.2 million. This license agreement (a) will automatically terminate if we file, or become subject to an involuntary filing, for bankruptcy, and (b) may be terminated by UBC in the event of, among other things, our insolvency, dissolution, grant of a security interest in the technology licensed to us pursuant to the license agreement, or material breach of or failure to perform material obligations under the license agreement or other research agreements between us and UBC.

Oral BDP License Agreement

On November 24, 1998, the Company, known at the time as Enteron Pharmaceuticals, Inc. (“Enteron”) and George B. McDonald (“Dr. McDonald”) entered into an exclusive license agreement for the rights to intellectual property, including know-how, relating to oral BDP. We have an exclusive license to commercially exploit the covered products worldwide, subject to Dr. McDonald’s right to make and use the technology for research purposes and the U.S. Government’s right to use the technology for government purposes. Pursuant to the license agreement, as amended, we are required to (i) reimburse Dr. McDonald for certain out-of-pocket expenses incurred by Dr. McDonald in connection with the patent applications and issued patents, (ii) pay Dr. McDonald $300,000 upon approval by the FDA of our first NDA incorporating oral BDP; (iii) pay Dr. McDonald royalty payments equal to 3% of net sales of the covered products and (iv) pay Dr. McDonald $400,000 in cash upon an approval of oral BDP by the European Medicines Agency.

Additionally, in the event that we sublicense our rights under the license agreement, we will be required to pay Dr. McDonald 10% of any sublicense fees and royalty payments paid by the sublicense to us.

The term of the license agreement expires upon the expiration of the licensed patent applications or patents. Dr. McDonald has the right to terminate the license agreement in its entirety or to terminate exclusivity under the agreement if we or its sublicenses have not commercialized or are not actively attempting to commercialize a covered product.

Additionally, the agreement terminates: (i) automatically upon us becoming insolvent; (ii) upon 30 days’ notice, if we breach any obligation under the agreement without curing such breach during the notice period; and (iii) upon 90 days’ notice by us. After any termination, we will have the right to sell our inventory for a period not to exceed three months following the date of termination, subject to the payment of the amounts owed under the agreement.

ThermoVax® License Agreement

On December 21, 2010, we executed a worldwide exclusive license agreement with the UC for ThermoVax®, which is the subject of U.S. patent number 8,444,991 issued on May 21, 2013 titled “Method of Preparing an Immunologically-Active Adjuvant-Bound Dried Vaccine Composition.” This patent and its corresponding foreign filings are licensed to us by the UC and they address the use of adjuvants in conjunction with vaccines that are formulated to resist thermal inactivation. U.S. Patent 8,444,991 is expected to expire in December 2031. The license agreement also covers thermostable vaccines for biodefense as well as other potential vaccine indications. In addition, we, in conjunction with UC, filed domestic and foreign patent applications claiming priority back to a provisional application filed on May 17, 2011 titled: “Thermostable Vaccine Compositions and Methods of Preparing Same.” In April 2018, the UC delivered a notice of termination of our license agreement based upon our failure to achieve one of the development milestones: initiation of the Phase 1 clinical trial of the heat stabilization technology by March 31, 2018. After negotiating with the UC, we and the UC agreed to extend the termination date to October 31, 2018 in order to allow us time to agree upon a potential agreement that would allow us to keep the rights to, and to continue to develop, the heat stabilization technology or a product candidate containing the heat stabilization technology in our field of use.

On October 31, 2018, in a series of related transactions, (a) we and the UC agreed to terminate the original license agreement, (b) the UC and VitriVax executed a worldwide exclusive license agreement for the heat stabilization technology for all fields of use, and (c) we and VitriVax executed a worldwide exclusive sublicense agreement, which was amended and restated in October 2020, for the heat stabilization technology for use in the fields of ricin and Ebola vaccines. We paid a $100,000 sublicense fee on the effective date of the sublicense agreement. Under the amended sublicense agreement to maintain the sublicense we are obliged to pay a minimum annual royalty of $20,000 until first commercial sale of a

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sublicensed product, upon which point, we will be required to pay an earned royalty of 2% of net sales subject to a minimum royalty of $50,000 each year. We are also required to pay royalties on any sub-sublicense income based on a declining percentage of all sub-sublicense income calculated within the contractual period until reaching a minimum of 15% after two years. In addition, we are required to pay VitriVax milestone fees of: (a) $25,000 upon initiation of a Phase 2 clinical trial of the sublicensed product, (b) $100,000 upon initiation of a Phase 3 clinical trial of the sublicensed product, (c) $100,000 upon regulatory approval of a sublicensed product, and (d) $1 million upon achieving $10 million in aggregate net sales of a sublicensed product in the U.S. or equivalent. To date none of these milestones have been met.

RiVax® License Agreement

In June 2003, we executed a worldwide exclusive option to license patent applications with UTSW for the nasal, pulmonary and oral uses of a non-toxic ricin vaccine. In June 2004, we entered into a license agreement with UTSW for the injectable rights to the ricin vaccine and, in October 2004, we negotiated the remaining oral rights to the ricin vaccine. To maintain this license, we are obligated to pay $50,000 in annual license fees. Through this license, we have rights to the issued patent number 7,175,848 titled “Ricin A chain mutants lacking enzymatic activity as vaccines to protect against aerosolized ricin.” This patent includes methods of use and composition claims for RiVax®.

CoVaccine HTTM License Agreement

In April 2020, we executed an agreement for the exclusive worldwide license of CoVaccine HTTM, a novel vaccine adjuvant, from BTG, a division of Boston Scientific Corporation (NYSE: BSX), for the fields of SARS-CoV-2, the cause of COVID-19 and pandemic flu. The agreement was executed with Protherics Medicines Development, one of the companies that make up the BTG specialty pharmaceuticals business, which owns the CoVaccine HTTM intellectual property.

Research and Development Expenditures

We spent approximately $8.4 million and $9.8 million in the years ended December 31, 2021 and 2020, respectively, on research and development. The amounts we spent on research and development per product during the years ended December 31, 2021 and 2020 are set forth in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in this Annual Report on Form 10-K.

Human Capital

We are committed to a work environment that is welcoming, inclusive and encouraging. To achieve our plans and goals, it is imperative that we attract and retain top talent. In order to do so, we aim to have a safe and encouraging workplace, with opportunities for our employees to grow and develop professionally, supported by strong compensation, benefits, and other incentives. In addition to competitive base salaries, we offer every full-time employee a cash target bonus, a comprehensive benefits package and equity compensation.

As of December 31, 2021, we employed a total of 15 persons, including 2 part-time employee and 13 full-time employees, five of whom are MDs/PhDs. In addition to our employees, we contract with third-parties for the conduct of certain clinical development, manufacturing, accounting and administrative activities. We anticipate increasing the number of our employees. We have no collective bargaining agreements with our employees, and none are represented by labor unions. We consider our relationships with our employees to be good.

Throughout the COVID 19 pandemic, many of our employees have worked remotely. In September 2021 our employees returned to the Company’s facilities in-person. We implemented a number of significant safety measures based on current guidelines recommended by the Centers for Disease Control. These include, but are not limited to, social distancing, capacity limitations, mask requirements in common areas, weekly deep cleaning and daily sanitation procedures.

Available Investor Information

We file electronically with the Securities and Exchange Commission (“SEC”) our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) of 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). We make available through our website, free of charge, copies of these reports as soon as reasonably practicable after we electronically file or

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furnish them to the SEC. Our website is located at www.soligenix.com. You can also request copies of such documents by contacting the company at (609) 538-8200 or sending an email to info@soligenix.com.

Item 1A. Risk factors

An investment in our securities involves a high degree of risk. You should carefully consider the following information about these risks, together with the other information about these risks contained in this Annual Report, as well as the other information contained in this Annual Report generally, before deciding to buy our securities. Any of the risks we describe below could adversely affect our business, financial condition, operating results or prospects. The market prices for our securities could decline if one or more of these risks and uncertainties develop into actual events and you could lose all or part of your investment. Additional risks and uncertainties that we do not yet know of, or that we currently think are immaterial, may also impair our business operations. You should also refer to the other information contained in this Annual Report, including our financial statements and the related notes.

Summary of Risk Factors

Our business is subject to a number of risks and uncertainties that you should understand before making an investment decision. These risks include, but are not limited to, the following:

Risks Related to our Business

● There may be unforeseen challenges in developing our biodefense products.

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● We may not be able to utilize all of our net operating loss carryforwards.

Risks Related to our Intellectual Property

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Risks Related to our Securities

● The price of our common stock and warrants may be highly volatile.

Risks Related to our Business

We have had significant losses and anticipate future losses; if additional funding cannot be obtained, we may reduce or discontinue our product development and commercialization efforts.

We have experienced significant losses since inception and, at December 31, 2021, had an accumulated deficit of approximately $206 million. We expect to incur additional operating losses in the future and expect our cumulative losses to increase. As of December 31, 2021, we had approximately $26 million in cash and cash equivalents available, and as of March 22, 2022 we had approximately $23.1 million in cash and cash equivalents available. Based on our projected budgetary needs, funding from existing contracts and grants over the next year and sales pursuant to our At Market Issuance Sales Agreement (“B. Riley Sales Agreement”) with B. Riley Securities, Inc. (“B. Riley”), we expect to be able to maintain the current level of our operations through at least March 31, 2023.

In September 2014, we entered into a contract with the NIH for the development of RiVax® to protect against exposure to ricin toxin that would provide up to $24.7 million of funding in the aggregate over six years if options to extend the contract are exercised by the NIH. In 2017, we were awarded two separate grants from the NIH of approximately $1.5 million each to support our pivotal Phase 3 trials of HyBryteTM for the treatment of CTCL and SGX942 for the treatment of oral mucositis in head and neck cancer. In December 2020, we were awarded Direct to Phase II SBIR grant from NIAID of approximately $1.5 million to support manufacture, formulation (including thermostabilization) and characterization of COVID-19 and EVD vaccine candidates in conjunction with the CoVaccine HTTM adjuvant. Our biodefense grants have an overhead component that allows us an agency-approved percentage over our incurred costs. We estimate that the overhead component associated with our existing contracts and grants will fund some fixed costs for direct employees working on these contracts and grants as well as other administrative costs. As of December 31, 2021, we had approximately $1.35 million in awarded grant funding available.

Our product candidates are positioned for or are currently in clinical trials, and we have not yet generated any significant revenues from sales or licensing of these product candidates. From inception through December 31, 2021, we have expended approximately $108 million developing our current product candidates for pre-clinical research and development and clinical trials. We currently expect to spend approximately $12.9 million for the year ending December 31, 2022 in connection with the development of our therapeutic and vaccine products, licenses, employment agreements, and consulting agreements, of which approximately $1.30 million is expected to be reimbursed through our existing government contracts and grants.

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We have no control over the resources and funding NIH, BARDA and NIAID may devote to our programs, which may be subject to periodic renewal and which generally may be terminated by the government at any time for convenience. Any significant reductions in the funding of U.S. government agencies or in the funding areas targeted by our business could materially and adversely affect our biodefense program and our results of operations and financial condition. If we fail to satisfy our obligations under the government contracts, the applicable Federal Acquisition Regulations allow the government to terminate the agreement in whole or in part, and we may be required to perform corrective actions, including but not limited to delivering to the government any incomplete work. If NIH, BARDA or NIAID do not exercise future funding options under the contracts or grants, terminate the funding or fail to perform their responsibilities under the agreements or grants, it could materially impact our biodefense program and our financial results.

Unless and until we are able to generate sales or licensing revenue from one of our product candidates, we will require additional funding to meet these commitments, sustain our research and development efforts, provide for future clinical trials, and continue our operations. There can be no assurance we can raise such funds. If additional funds are raised through the issuance of equity securities, stockholders may experience dilution of their ownership interests, and the newly issued securities may have rights superior to those of the common stock. If additional funds are raised by the issuance of debt, we may be subject to limitations on our operations. If we cannot raise such additional funds, we may have to delay or stop some or all of our drug development programs.

If we are unable to develop our product candidates, our ability to generate revenues and viability as a company will be significantly impaired.

In order to generate revenues and profits, our organization must, along with corporate partners and collaborators, positively research, develop and commercialize our technologies or product candidates. Our current product candidates are in various stages of clinical and pre-clinical development and will require significant further funding, research, development, pre-clinical and/or clinical testing, regulatory approval and commercialization, and are subject to the risks of failure inherent in the development of products based on innovative or novel technologies. Specifically, each of the following is possible with respect to any of our product candidates:

● we may not be able to maintain our current research and development schedules;

● we may encounter problems in clinical trials; or

If any of the risks set forth above occur, or if we are unable to obtain the necessary regulatory approvals as discussed below, we may be unable to develop our technologies and product candidates and our business will be seriously harmed. Furthermore, for reasons including those set forth below, we may be unable to commercialize or receive royalties from the sale of any other technology we develop, even if it is shown to be effective, if:

● we are not able to manufacture the product reliably;

● others have brought to market similar or superior products; or

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We expect a number of factors to cause our operating results to fluctuate on a quarterly and annual basis, which may make it difficult to predict our future performance.

We are a late-stage biopharmaceutical company. Our operations to date have been primarily limited to developing our technology and undertaking pre-clinical studies and clinical trials of our product candidates in our two active business segments, Specialized BioTherapeutics and Public Health Solutions. We have not yet obtained regulatory approvals for any of our product candidates. Consequently, any predictions made about our future success or viability may not be as accurate as they could be if we had commercialized products. Our financial condition has varied significantly in the past and will continue to fluctuate from quarter-to-quarter or year-to-year due to a variety of factors, many of which are beyond our control. Factors relating to our business that may contribute to these fluctuations include other factors described elsewhere in this Annual Report and also include:

● our ability to obtain additional funding to develop our product candidates;

● our ability to repay existing debt in accordance with its terms;

● delays in the commencement, enrollment and timing of clinical trials;

● market acceptance of our product candidates;

● competition from existing products or new products that may emerge;

● our ability to discover and develop additional product candidates;

● potential product liability claims;

● potential liabilities associated with hazardous materials; and

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● our ability to obtain and maintain adequate insurance policies.

Accordingly, the results of any quarterly or annual periods should not be relied upon as indications of future operating performance.

We have no approved products on the market and therefore do not expect to generate any revenues from product sales in the foreseeable future, if at all.

To date, we have no approved product on the market and have not generated any significant product revenues. We have funded our operations primarily from sales of our securities and from government contracts and grants. We have not received, and do not expect to receive for at least the next several years, if at all, any revenues from the commercialization of our product candidates. To obtain revenues from sales of our product candidates, we must succeed, either alone or with third parties, in developing, obtaining regulatory approval for, manufacturing and marketing drugs with commercial potential or successfully obtain government procurement or stockpiling agreements. We may never succeed in these activities, and we may not generate sufficient revenues to continue our business operations or achieve profitability.

Our business is subject to extensive governmental regulation, which can be costly, time consuming and subjects us to unanticipated delays.

Our business is subject to very stringent federal, foreign, state and local government laws and regulations, including the Federal Food, Drug and Cosmetic Act, the Environmental Protection Act, the Occupational Safety and Health Act, and state and local counterparts to these acts. These laws and regulations may be amended, additional laws and regulations may be enacted, and the policies of the FDA and other regulatory agencies may change.

SNGX US Equity

SNGX · 10-K · period ended 2021-12-31

Item 1. Business

Item 1A. Risk factors

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SNGX · 10-K · period ended 2021-12-31

Item 1. Business

Item 1A. Risk factors

SNGX US Equity