S-8 1 tm2621644d1_s8.htm FORM S-8

As filed with the Securities and Exchange Commission on August 5, 2026.

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

PROTAGONIST THERAPEUTICS, INC.

(Exact name of Registrant as specified in its charter)

Delaware	2834	98-0505495

(State or other jurisdiction of incorporation or organization)	(Primary Standard Industrial Classification Code Number)	(I.R.S. Employer Identification Number)

7707 Gateway Boulevard, Suite 140

Newark, California 94560

(510) 474-0170

(Address, including zip code and telephone number, of Registrant’s principal executive offices)

Protagonist Therapeutics, Inc. 2026 Equity Incentive Plan

(Full title of the plan)

Dinesh V. Patel, Ph.D.

President and Chief Executive Officer

7707 Gateway Boulevard, Suite 140

Newark, California 94560

(510) 474-0170

(Name, address, including zip code and telephone number, including area code, of agent for service)

Copies to:

Ryan Murr

Gibson, Dunn & Crutcher LLP

One Embarcadero Center

Suite 2600

San Francisco, California 94111

415-393-8200

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

Large accelerated filer	x	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 7(a)(2)(B) of the Securities Act. ¨

EXPLANATORY NOTE

Protagonist Therapeutics, Inc. (the “Registrant”) is filing this Registration Statement on Form S-8 (this “Registration Statement”) for the purpose of registering 650,000 shares of common stock, $0.00001 par value per share (the “Common Stock”), issuable to eligible persons under the Registrant’s 2026 Equity Incentive Plan.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

The information required by this Part I has been omitted from this Registration Statement pursuant to the Note to Part I of Form S-8.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.

Incorporation of Documents by Reference.

The following documents filed by the Registrant with the Securities and Exchange Commission (the “Commission”) are incorporated by reference herein and shall be deemed to be a part hereof:

The Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 filed with the Commission on February 25, 2026;

The Registrant’s Quarterly Reports on Form 10-Q for the fiscal quarters ended March 31, 2026 and June 30, 2026 filed with the Commission on May 5, 2026 and August 5, 2026;

The Registrant’s Current Report on Form 8-K filed with the Commission on June 18, 2026; and

The description of the Common Stock contained in the Registrant’s Registration Statement on Form 8-A/A filed with the Commission under Section 12(b) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), on August 9, 2016, as updated by Exhibit 4.2 to the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 filed with the Commission on February 21, 2025, together with any amendments or reports filed for the purpose of updating such description.

In addition, all documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date hereof, but prior to the filing of a post-effective amendment to this Registration Statement that indicates that all securities offered hereby have been sold or that deregisters all such securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing of such documents. Notwithstanding the foregoing, unless specifically stated to the contrary in such filing, none of the information that the Registrant discloses under Items 2.02 or 7.01 of any Current Report on Form 8-K that it may from time to time furnish to the Commission will be incorporated by reference into, or otherwise be included in or deemed to be a part of, this Registration Statement.

For purposes of this Registration Statement, any document or any statement contained in a document incorporated or deemed to be incorporated herein by reference shall be deemed to be modified or superseded to the extent that a subsequently filed document or a statement contained herein or in any other subsequently filed document that also is or is deemed to be incorporated herein by reference modifies or supersedes such document or such statement in such document. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement. Subject to the foregoing, all information in this Registration Statement is so qualified in its entirety by the information appearing in the documents incorporated herein by reference.

Item 4.

Description of Securities.

Not applicable.

Item 5.

Interests of Named Experts and Counsel.

Not applicable.

Item 6.

Indemnification of Directors and Officers.

Section 145 of the Delaware General Corporation Law authorizes a court to award, or a corporation’s board of directors to grant, indemnity to directors and officers in terms sufficiently broad to permit such indemnification under certain circumstances for liabilities, including reimbursement for expenses incurred, arising under the Securities Act of 1933, as amended (the “Securities Act”).

The Registrant’s amended and restated certificate of incorporation and amended and restated bylaws provide that the Registrant will indemnify its directors and officers, and may indemnify its employees and other agents, to the fullest extent permitted by the Delaware General Corporation Law. However, Delaware law prohibits the Registrant’s certificate of incorporation from limiting the liability of the Registrant’s directors for the following:

· any breach of the director’s duty of loyalty to the Registrant or its stockholders;

· acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;

· unlawful payment of dividends or unlawful stock repurchases or redemptions; and

· any transaction from which the director derived an improper personal benefit.

The Registrant has entered into indemnification agreements with each of its directors and officers. These agreements provide for the indemnification of such persons for all reasonable expenses and liabilities incurred in connection with any action or proceeding brought against them by reason of the fact that they are or were serving in such capacity.

The Registrant may maintain insurance policies that indemnify its directors and officers against various liabilities arising under the Securities Act and the Exchange Act that might be incurred by any director or officer in his or her capacity as such. The Registrant has obtained director and officer liability insurance to cover liabilities directors and officers may incur in connection with their services to the Registrant.

Item 7.

Exemption from Registration Claimed.

Not applicable.

ITEM 8.

EXHIBITS

Exhibit Number		Description
4.1 (1)		Amended and Restated Certificate of Incorporation of Protagonist Therapeutics, Inc.
4.2 (2)		Certificate of Amendment to the Amended and Restated Certificate of Incorporation of Protagonist Therapeutics, Inc.
4.3 (3)		Amended and Restated Bylaws of Protagonist Therapeutics, Inc.
4.4 (4)		Specimen stock certificate evidencing the shares of Common Stock.
5.1*		Opinion of Gibson, Dunn & Crutcher LLP.
23.1*		Consent of Gibson, Dunn & Crutcher LLP (included in Exhibit 5.1).
23.2*		Consent of independent registered public accounting firm.
24.1*		Power of Attorney (included on the signature page of this Form S-8).
99.1 (5)		Protagonist Therapeutics, Inc. 2026 Equity Incentive Plan.
107.1*		Calculation of Filing Fee Table.

(1)	Filed as Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (File No. 001-37852), filed with the Commission on August 16, 2016, and incorporated herein by reference.
(2)	Filed as Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (File No. 001-37852), filed with the Commission on June 26, 2024, and incorporated herein by reference.
(3)	Filed as Exhibit 3.2(b) to the Registrant’s Registration Statement on Form S-1/A (File No. 333-212476), filed with the Commission on August 1, 2016, and incorporated herein by reference.
(4)	Filed as Exhibit 4.1 to the Registrant’s Registration Statement on Form S-1/A (File No. 333-212476), filed with the Commission on August 1, 2016, and incorporated herein by reference.
(5)	Filed as Exhibit 10.1 to the Registrant’s Current Report on Form 8-K (File No. 001-37852), filed with the Commission on June 18, 2026, and incorporated herein by reference.
*	Filed herewith.

Item 9. Undertakings.

(a) The undersigned Registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) To reflect in the prospectus any facts or events arising after the effective date of this Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this Registration Statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the “Calculation of Filing Fee Tables” in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in this Registration Statement or any material change to such information in this Registration Statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in this Registration Statement;

(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; and

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in this Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

SIGNATURES

Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Newark, State of California, on this 5th day of August, 2026.

PROTAGONIST THERAPEUTICS, INC.

By:	/s/ Dinesh V. Patel, Ph.D.
	Dinesh V. Patel, Ph.D.
	President and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Dinesh V. Patel, Ph.D. and Asif Ali, and each or any one of them, as his or her true and lawful attorney-in-fact and agent, each with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or his substitutes or substitute, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ Dinesh V. Patel, Ph.D.	President, Chief Executive Officer and Director	August 5, 2026
Dinesh V. Patel, Ph.D.	(Principal Executive Officer)

/s/ Asif Ali	Chief Financial Officer	August 5, 2026
Asif Ali	(Principal Financial and Accounting Officer)

/s/ Harold E. Selick, Ph.D.	Chairman of the Board of Directors	August 5, 2026
Harold E. Selick, Ph.D.

/s/ Bryan Giraudo	Director	August 5, 2026
Bryan Giraudo

/s/ Sarah O’Dowd	Director	August 5, 2026
Sarah O’Dowd

/s/ William D. Waddill	Director	August 5, 2026
William D. Waddill

/s/ Lewis T. Williams, M.D., Ph.D.	Director	August 5, 2026
Lewis T. Williams, M.D., Ph.D.