Part I [Business](index=5&type=section&id=Item%201.%20Business) Soligenix is a late-stage biopharmaceutical company with two segments: rare diseases (HyBryte™) and biodefense (RiVax®) - The company operates through two distinct business segments: **Specialized BioTherapeutics** for rare diseases and **Public Health Solutions** for biodefense and emerging infectious diseases[15](index=15&type=chunk) - A key strategic focus is to address the **FDA Refusal to File (RTF) letter** for lead candidate **HyBryte™** to advance it towards marketing approval for Cutaneous T-Cell Lymphoma (CTCL)[18](index=18&type=chunk)[49](index=49&type=chunk) - The **Public Health Solutions segment** is heavily reliant on **U.S. government funding** from agencies like NIAID, BARDA, and DTRA for its vaccine and therapeutic candidates[17](index=17&type=chunk) [Specialized BioTherapeutics Product Candidates](index=7&type=section&id=Specialized%20BioTherapeutics%20Product%20Candidates) The Specialized BioTherapeutics pipeline is led by **HyBryte™** for CTCL, which completed Phase 3 but faces FDA regulatory hurdles Specialized BioTherapeutics Pipeline Status | Product Candidate | Indication | Stage of Development | | :--- | :--- | :--- | | **HyBryte™ (SGX301)** | Cutaneous T-Cell Lymphoma | Phase 3 completed; NDA submitted Dec 2022; FDA RTF letter received Feb 2023 | | **SGX302** | Mild-to-Moderate Psoriasis | Phase 2a study initiated Dec 2022 | | **SGX942** | Oral Mucositis in Head and Neck Cancer | Phase 3 results did not meet primary endpoint for statistical significance; requires a second Phase 3 trial and partnership | | **SGX203** | Pediatric Crohn's disease | Phase 1/2 completed; Phase 3 initiation contingent upon partnership/funding | HyBryte™ Phase 3 FLASH Study Response Rates | Treatment Cycle | Duration | Response Rate (≥50% reduction in CAILS) | Comparison Group | p-value | | :--- | :--- | :--- | :--- | :--- | | Cycle 1 | 6 weeks | 16% | 4% (Placebo) | 0.04 | | Cycle 2 | 12 weeks | 40% | Placebo / 6-weeks treatment | <0.0001 | | Cycle 3 | 18 weeks | 49% | 12-weeks treatment (Cycle 2) | 0.046 | - In February 2023, the company received a **Refusal to File (RTF) letter** from the FDA for the HyBryte™ NDA, indicating the application was not sufficiently complete for substantive review[49](index=49&type=chunk) - The Phase 3 trial for SGX942 in oral mucositis did not meet its primary endpoint for statistical significance (p≤0.05), although it showed a clinically meaningful **56% reduction** in the median duration of severe oral mucositis, with further development contingent on securing a partner[73](index=73&type=chunk)[74](index=74&type=chunk) [Public Health Solutions Product Candidates](index=8&type=section&id=Public%20Health%20Solutions%20Product%20Candidates) This segment focuses on biodefense and infectious diseases, leveraging **ThermoVax®** for heat-stable vaccines like **RiVax®** Public Health Solutions Pipeline Status | Product Candidate | Indication | Stage of Development | | :--- | :--- | :--- | | **ThermoVax®** | Vaccine Thermostability Platform | Pre-clinical | | **RiVax®** | Vaccine against Ricin Toxin | Phase 1a/1b completed; Phase 1c initiated Dec 2019 but suspended Jan 2020 due to manufacturing issues | | **SGX943** | Therapeutic against Emerging Infectious Diseases | Pre-clinical | | **CiVax™** | Vaccine against COVID-19 | Pre-clinical | - The **ThermoVax® platform technology** aims to eliminate the need for a cold chain for vaccines by creating thermostable formulations, potentially reducing waste and distribution costs[88](index=88&type=chunk)[89](index=89&type=chunk) - The RiVax® Phase 1c study was suspended in January 2020 after the drug substance manufacturer, Emergent Manufacturing Operations Baltimore LLC (EMOB), notified the company that the active drug substance tested outside of established specifications[113](index=113&type=chunk) - The company filed a demand for arbitration against Emergent BioSolutions in July 2020, seeking over **$19 million** in damages related to manufacturing failures of RiVax®, with the panel finding breaches of contract but not awarding monetary damages, a decision Soligenix is challenging[115](index=115&type=chunk)[351](index=351&type=chunk) [Regulatory, Manufacturing, and Commercialization](index=21&type=section&id=Regulatory%2C%20Manufacturing%2C%20and%20Commercialization) The company navigates complex drug approval processes, utilizing **Orphan Drug** and **Fast Track** designations, outsourcing manufacturing, and seeking partnerships - The company utilizes regulatory pathways such as **Orphan Drug Designation** (granted for HyBryte™, SGX203, RiVax®) and **Fast Track Designation** (granted for HyBryte™, SGX942, RiVax®) to facilitate development and potentially gain market exclusivity[38](index=38&type=chunk)[82](index=82&type=chunk)[118](index=118&type=chunk)[139](index=139&type=chunk)[140](index=140&type=chunk) - Soligenix outsources all drug substance and product manufacturing to third-party suppliers and does not intend to develop its own manufacturing infrastructure[154](index=154&type=chunk) - The company has an exclusive license agreement with SciClone Pharmaceuticals for the development and commercialization of SGX942 in Greater China, South Korea, and Vietnam[161](index=161&type=chunk) [Patents and Proprietary Rights](index=28&type=section&id=Patents%20and%20Proprietary%20Rights) Soligenix's IP strategy relies on patents and regulatory exclusivities, with key patents for **HyBryte™**, **SGX94**, and **ThermoVax®** extending to 2040 - HyBryte™ (synthetic hypericin) is protected by a composition of matter patent (U.S. patent 8,629,302) expected to expire in **September 2030** and a manufacturing process patent (U.S. patent 10,053,513) expected to expire in **2036**[178](index=178&type=chunk) - The SGX94 (dusquetide) technology is covered by composition of matter patents including U.S. patent 8,124,721 (expiring **2028**) and 8,791,061 (expiring **2029**)[180](index=180&type=chunk) - The ThermoVax® heat stabilization technology is licensed from VitriVax, Inc. and is covered by U.S. patents 8,444,991 (expiring **February 2030**) and 8,808,710 (expiring **March 2028**)[184](index=184&type=chunk)[196](index=196&type=chunk) [Risk Factors](index=32&type=section&id=Item%201A.%20Risk%20Factors) The company faces significant risks including substantial losses, a **$219.6 million accumulated deficit**, going concern doubts, clinical/regulatory hurdles, and reliance on third-party manufacturers - The company has a history of significant losses, with an accumulated deficit of approximately **$219.6 million** as of December 31, 2022, and expects to incur future losses[216](index=216&type=chunk) - The company's operating losses, negative cash flows, and projected potential breach of a debt covenant raise substantial doubt about its ability to continue as a going concern, as noted in the independent auditor's report[224](index=224&type=chunk)[228](index=228&type=chunk) - The company is highly dependent on uncertain government funding for its Public Health Solutions business segment[246](index=246&type=chunk) - Soligenix relies on third-party suppliers for all manufacturing, and any disruption could delay or impair its ability to develop and market products[249](index=249&type=chunk)[250](index=250&type=chunk) - The company received a notice from Nasdaq in December 2022 for non-compliance with the minimum bid price and shareholders' equity requirements, with a reverse stock split helping regain bid price compliance, but shareholders' equity compliance still pending[325](index=325&type=chunk)[327](index=327&type=chunk)[329](index=329&type=chunk) [Properties](index=54&type=section&id=Item%202.%20Properties) Soligenix leases **6,200 square feet** of office space in Princeton, NJ, as its corporate headquarters, with the lease extended through October 2025 - The company leases approximately **6,200 square feet** of office space in Princeton, NJ, which serves as its corporate headquarters[345](index=345&type=chunk) - The current lease has been extended through **October 2025**, with monthly rent starting at approximately **$11,108** and increasing annually[345](index=345&type=chunk) [Legal Proceedings](index=54&type=section&id=Item%203.%20Legal%20Proceedings) The company initiated arbitration against **Emergent BioSolutions** over **RiVax®** manufacturing, with the panel finding breaches but no monetary damages, a decision Soligenix is challenging - In July 2020, Soligenix initiated arbitration against Emergent BioSolutions, alleging breach of contract and fraud concerning the manufacture of RiVax® bulk drug substance[347](index=347&type=chunk) - The arbitration panel's final decision in July 2022 found that Emergent had committed breaches of contract but did not award monetary damages to Soligenix[351](index=351&type=chunk) - On September 30, 2022, Soligenix filed a petition with the Delaware Court of Chancery to vacate the arbitration decision and remand the matter for rehearing[351](index=351&type=chunk) Part II [Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities](index=55&type=section&id=Item%205.%20Market%20for%20Registrant%27s%20Common%20Equity%2C%20Related%20Stockholder%20Matters%20and%20Issuer%20Purchases%20of%20Equity%20Securities) Soligenix's common stock trades on Nasdaq under **SNGX**, experiencing volatility, with **2,924,491 shares outstanding** and no plans for cash dividends Common Stock Price Range (2022) | Quarter | High ($) | Low ($) | | :--- | :--- | :--- | | First Quarter | 13.65 | 8.70 | | Second Quarter | 12.00 | 5.70 | | Third Quarter | 15.00 | 6.45 | | Fourth Quarter | 10.95 | 5.85 | - As of March 24, 2023, there were **2,924,491 shares** of common stock outstanding[359](index=359&type=chunk) - The company has never paid cash dividends and does not intend to in the foreseeable future[360](index=360&type=chunk) [Management's Discussion and Analysis of Financial Condition and Results of Operations](index=56&type=section&id=Item%207.%20Management%27s%20Discussion%20and%20Analysis%20of%20Financial%20Condition%20and%20Results%20of%20Operations) In 2022, Soligenix reported a **net loss of $13.8 million**, revenues of **$0.95 million**, and a **49% decrease in cash to $13.4 million**, raising substantial doubt about its going concern Financial Results Comparison (2022 vs. 2021) | Metric | 2022 | 2021 | | :--- | :--- | :--- | | **Net Loss** | $13,798,339 | $12,550,973 | | **Total Revenues** | $948,911 | $824,268 | | **Research & Development Expenses** | $7,944,089 | $8,185,850 | | **General & Administrative Expenses** | $6,692,904 | $5,008,738 | - The increase in net loss was primarily driven by a **34% increase in G&A expenses**, largely due to legal and consulting costs associated with the arbitration against Emergent[381](index=381&type=chunk)[387](index=387&type=chunk) - As of December 31, 2022, cash and cash equivalents were **$13.4 million**, a **49% decrease** from **$26.0 million** at year-end 2021, with the company having a working capital deficit of **$2.7 million**[394](index=394&type=chunk) - Management has concluded that there is substantial doubt about the company's ability to continue as a going concern, with sufficient cash to fund operations only into the third quarter of 2023[396](index=396&type=chunk)[547](index=547&type=chunk) [Controls and Procedures](index=66&type=section&id=Item%209A.%20Controls%20and%20Procedures) Management concluded that the company's disclosure controls and internal control over financial reporting were **effective** as of December 31, 2022 - Management concluded that the company's disclosure controls and procedures were effective as of the end of the period covered by the report (December 31, 2022)[431](index=431&type=chunk) - Based on an assessment using the COSO framework, management concluded that the company's internal control over financial reporting was effective as of December 31, 2022[436](index=436&type=chunk) Part III [Directors, Executive Officers and Corporate Governance](index=67&type=section&id=Item%2010.%20Directors%2C%20Executive%20Officers%20and%20Corporate%20Governance) The company's leadership includes Dr. Christopher J. Schaber as CEO, with a five-member Board (four independent) and three committees: Audit, Compensation, and Nominating and Corporate Governance - Dr. Christopher J. Schaber serves as Chairman of the Board, Chief Executive Officer, and President[442](index=442&type=chunk) - The Board of Directors has determined that Gregg A. Lapointe, Diane L. Parks, Robert J. Rubin, and Jerome B. Zeldis are independent directors[497](index=497&type=chunk) - The Board maintains an Audit Committee, a Compensation Committee, and a Nominating and Corporate Governance Committee, each with a written charter[457](index=457&type=chunk) [Executive Compensation](index=72&type=section&id=Item%2011.%20Executive%20Compensation) The Summary Compensation Table details executive pay, with CEO Christopher J. Schaber's total compensation at **$711,185** in 2022, and directors receiving cash and stock option grants 2022 Summary Compensation for Named Executive Officers | Name | Position | Salary ($) | Bonus ($) | Option Awards ($) | Total ($) | | :--- | :--- | :--- | :--- | :--- | :--- | | **Christopher J. Schaber** | CEO & President | 499,496 | 107,891 | 73,059 | 711,185 | | **Jonathan Guarino** | CFO & Senior VP | 231,132 | 42,436 | 51,042 | 355,350 | | **Oreola Donini** | CSO & Senior VP | 280,800 | 51,555 | 27,259 | 364,242 | | **Richard C. Straube** | CMO & Senior VP | 182,174 | 32,901 | 27,259 | 242,334 | - Independent directors receive an annual cash retainer of **$35,000**, with additional fees for committee chairs and members, and stock option grants valued at **$30,000** upon re-election[486](index=486&type=chunk) [Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters](index=76&type=section&id=Item%2012.%20Security%20Ownership%20of%20Certain%20Beneficial%20Owners%20and%20Management%20and%20Related%20Stockholder%20Matters) As of March 24, 2023, directors and executive officers as a group beneficially owned **4.1%** of common stock, with **5,812,991 shares** available for future equity grants - As of March 24, 2023, all directors and executive officers as a group beneficially owned **125,616 shares**, representing **4.1%** of the outstanding common stock[488](index=488&type=chunk) - No individual or entity was reported as beneficially owning **5% or more** of the company's common stock[487](index=487&type=chunk) - As of December 31, 2022, there were **5,812,991 shares** available for future issuance under the company's equity compensation plans approved by security holders[490](index=490&type=chunk)[493](index=493&type=chunk) [Principal Accountant Fees and Services](index=79&type=section&id=Item%2014.%20Principal%20Accountant%20Fees%20and%20Services) EisnerAmper LLP, the independent auditor, billed **$167,265** in 2022 and **$180,561** in 2021, primarily for audit services, all pre-approved Accountant Fees (EisnerAmper LLP) | Fee Type | 2022 ($) | 2021 ($) | | :--- | :--- | :--- | | Audit Fees | 153,930 | 167,041 | | Tax Fees | 13,335 | 13,520 | | **Total** | **167,265** | **180,561** | Part IV [Exhibits and Financial Statement Schedules](index=79&type=section&id=Item%2015.%20Exhibits%20and%20Financial%20Statement%20Schedules) This section lists consolidated financial statements and a comprehensive list of exhibits, including corporate documents and material contracts - This section contains the consolidated financial statements for the years ended December 31, 2022 and 2021[506](index=506&type=chunk) - A list of exhibits is provided, incorporating by reference key corporate documents, material contracts like the Loan and Security Agreement with Pontifax, and executive employment agreements[510](index=510&type=chunk)[511](index=511&type=chunk)[512](index=512&type=chunk) Consolidated Financial Statements [Report of Independent Registered Public Accounting Firm](index=109&type=section&id=Report%20of%20Independent%20Registered%20Public%20Accounting%20Firm) EisnerAmper LLP issued an opinion on the financial statements, including a **Going Concern** paragraph due to recurring losses, and identified clinical trial expense accrual as a critical audit matter - The auditor's report contains an explanatory paragraph expressing substantial doubt about the Company's ability to continue as a going concern due to recurring losses from operations[649](index=649&type=chunk) - The accrual for clinical trial expenses was identified as a Critical Audit Matter, reflecting the significant judgment and subjectivity required by management in estimating these costs[653](index=653&type=chunk)[654](index=654&type=chunk) [Financial Statements Data](index=86&type=section&id=Financial%20Statements%20Data) As of December 31, 2022, total assets were **$14.3 million**, total liabilities **$16.8 million**, and a shareholders' deficit of **$2.5 million**, with a **net loss of $13.8 million** Consolidated Balance Sheet Highlights (As of Dec 31) | Metric | 2022 | 2021 | | :--- | :--- | :--- | | Cash and cash equivalents | $13,359,615 | $26,043,897 | | Total Assets | $14,279,717 | $26,869,927 | | Total Current Liabilities | $16,516,873 | $6,291,176 | | Total Liabilities | $16,750,500 | $16,147,329 | | Total Shareholders' Equity (Deficit) | ($2,470,826) | $10,722,598 | Consolidated Statement of Operations Highlights (Year Ended Dec 31) | Metric | 2022 | 2021 | | :--- | :--- | :--- | | Total Revenues | $948,911 | $824,268 | | Loss from Operations | ($14,238,904) | ($13,098,960) | | Net Loss | ($13,798,339) | ($12,550,973) | | Basic and Diluted Net Loss Per Share | ($4.81) | ($4.69) |

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Quarterly Period Ended September 30, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ____________ to ____________ Commission File No. 001-14778 SOLIGENIX, INC. (Exact name of registrant as specified in its charter) DELAWARE 41-15050 ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Quarterly Period Ended June 30, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ____________ to ____________ Commission File No. 000-16929 SOLIGENIX, INC. (Exact name of registrant as specified in its charter) DELAWARE 41-1505029 (S ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Quarterly Period Ended March 31, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ____________ to ____________ Commission File No. 000-16929 SOLIGENIX, INC. (Exact name of registrant as specified in its charter) DELAWARE 41-1505029 ( ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. For the Fiscal Year Ended December 31, 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) | Delaware | 41- ...

For the Quarterly Period Ended September 30, 2021 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY 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 j ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Quarterly Period Ended June 30, 2021 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ____________ to ____________ Commission File No. 000-16929 SOLIGENIX, INC. (Exact name of registrant as specified in its charter) (State or other jurisd ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Quarterly Period Ended March 31, 2021 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ____________ to ____________ Commission File No. 000-16929 SOLIGENIX, INC. (Exact name of registrant as specified in its charter) DELAWARE 41-1505029 (State or other jur ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. For the Fiscal Year Ended December 31, 2020 ☐ 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) | Delaware | 41-1505029 | | --- | --- | ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Quarterly Period Ended September 30, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ____________ to ____________ Commission File No. 000-16929 SOLIGENIX, INC. (Exact name of registrant as specified in its charter) DELAWARE 41-1505029 (State or other ...