424B3 1 sngx-20260807x424b3.htm 424B3

Prospectus Supplement No. 2

(To Prospectus dated March 31, 2026)

Filed Pursuant to Rule 424(b)(3)

Registration Statement No. 333-271049

408,640 shares of Common Stock Underlying Previously Issued Common Warrants

This Prospectus Supplement No. 2 (this “Prospectus Supplement”) supplements the prospectus dated March 31, 2026 (the “Final Prospectus”), relating to the offer and sale by us of 408,640 shares of common stock underlying common warrants previously issued by us.

This Prospectus Supplement contains the Quarterly Report on Form 10-Q for the quarter ended June 30, 2026 that we filed with the U.S. Securities and Exchange Commission on August 7, 2026. This Prospectus Supplement should be read in conjunction with, and may not be utilized without, the Final Prospectus, which is to be delivered with this Prospectus Supplement. This Prospectus Supplement is qualified by reference to the Final Prospectus except to the extent that the information in this Prospectus Supplement updates and supersedes the information contained in the Final Prospectus, including any supplements or amendments thereto.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Prospectus Supplement No. 2 dated August 7, 2026.

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, 2026

☐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		41-1505029
(State or other jurisdiction of		(I.R.S. Employer
incorporation or organization)		Identification Number)


29 EMMONS DRIVE, SUITE B-10 PRINCETON, NJ		08540
(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 $.001 per share	SNGX	The Nasdaq Capital Market

Indicate by check whether the registrant (1) 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 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, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.


Large accelerated filer	☐	Accelerated filer	☐
Non-accelerated filer	☒	Smaller reporting company	☒
		Emerging growth company	☐

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

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

As of July 31, 2026, 21,765,479 shares of the registrant’s common stock (par value, $.001 per share) were outstanding.

Table of Contents

SOLIGENIX, INC.

Index

		Description		Page

Part I		FINANCIAL INFORMATION		1

Item 1		Condensed Consolidated Financial Statements (unaudited)		1
		Condensed Consolidated Balance Sheets as of June 30, 2026 and December 31, 2025		1
		Condensed Consolidated Statements of Operations for the Three and Six Months Ended June 30, 2026 and 2025		2
		Condensed Consolidated Statements of Changes in Shareholders’ Equity for the Six Months Ended June 30, 2026 and 2025		3
		Condensed Consolidated Statements of Changes in Shareholders’ Equity for the Three Months Ended June 30, 2026 and 2025		4
		Condensed Consolidated Statements of Cash Flows for the Six Months Ended June 30, 2026 and 2025		5
		Notes to Condensed Consolidated Financial Statements		6
Item 2		Management’s Discussion and Analysis of Financial Condition and Results of Operations		18
Item 3		Quantitative and Qualitative Disclosures About Market Risk		41
Item 4		Controls and Procedures		41

Part II		OTHER INFORMATION		42

Item 1		Legal Proceedings		42
Item 1A		Risk Factors		42
Item 2		Unregistered Sales of Equity Securities and Use of Proceeds		44
Item 5		Other Information		44
Item 6		Exhibits		45

SIGNATURES				46

Table of Contents

PART I - FINANCIAL INFORMATION

ITEM 1 - FINANCIAL STATEMENTS

Soligenix, Inc. and Subsidiaries

Condensed Consolidated Balance Sheets


		June 30,			December 31,
		2026			2025
Assets		(unaudited)
Current assets:
Cash and cash equivalents		$	9,811,141		$	7,936,153
Deferred issuance cost			5,194			18,543
Prepaid expenses and other current assets			355,451			894,311
Total current assets			10,171,786			8,849,007
Security deposit			22,777			22,777
Furniture and equipment, net			6,577			8,772
Right-of-use lease assets			298,330			354,965
Total assets		$	10,499,470		$	9,235,521

Liabilities and shareholders' equity
Current liabilities:
Accounts payable		$	1,407,298		$	1,115,497
Accrued expenses			2,059,974			1,981,630
Accrued compensation			84,052			488,125
Lease liabilities, current			120,515			114,023
Total current liabilities			3,671,839			3,699,275
Non-current liabilities:
Lease liabilities, net of current portion			182,074			244,121
Total liabilities			3,853,913			3,943,396

Commitments and contingencies (Note 5)

Shareholders’ equity:
Preferred stock, 350,000 shares authorized; none issued or outstanding at June 30, 2026 and December 31, 2025			—			—
Common stock, $0.001 par value; 75,000,000 shares authorized; 21,637,479 and 10,086,130 shares issued and outstanding at June 30, 2026 and December 31, 2025, respectively			21,637			10,086
Additional paid-in capital			256,441,582			250,287,382
Accumulated other comprehensive income			45,789			45,789
Accumulated deficit			(249,863,451)			(245,051,132)
Total shareholders’ equity			6,645,557			5,292,125
Total liabilities and shareholders’ equity		$	10,499,470		$	9,235,521

The accompanying notes are an integral part of these condensed consolidated financial statements.

Table of Contents

Soligenix, Inc. and Subsidiaries

Condensed Consolidated Statements of Operations

For the Three and Six Months Ended June 30, 2026 and 2025

(Unaudited)


			Three Months Ended				Six Months Ended
			June 30,				June 30,
		2026		2025			2026		2025
Revenues:
Grant revenue		$	—	$	—		$	—	$	—
Total revenues			—		—			—		—
Cost of revenues			—		—			—		—
Gross profit			—		—			—		—
Operating expenses:
Research and development			974,091		1,677,014			2,756,391		3,618,694
General and administrative			1,125,372		1,086,865			2,227,910		2,171,693
Total operating expenses			2,099,463		2,763,879			4,984,301		5,790,387
Loss from operations			(2,099,463)		(2,763,879)			(4,984,301)		(5,790,387)
Other income (expense):
Foreign currency transaction gain (loss)			68		(8,045)			(1,448)		(8,833)
Interest income, net			53,598		69,823