S-8 POS

As filed with the Securities and Exchange Commission on September 11, 2017

Registration No. 333-218134

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1 ON

FORM S-8 TO FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ALPINE IMMUNE SCIENCES, INC.

(Exact name of registrant as specified in its charter)

Delaware	20-8969493
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
201 Elliott Avenue West, Suite 230 Seattle, WA	98119
(Address of Principal Executive Offices)	(Zip Code)

ALPINE IMMUNE SCIENCES, INC. (now known as AIS Operating Co., Inc.)

AMENDED AND RESTATED 2015 STOCK PLAN,

AS AMENDED

(Full title of the plan)

Mitchell H. Gold, M.D.

Executive Chairman and Chief Executive Officer

201 Elliott Avenue West, Suite 230

Seattle, WA 98119

Tel: (206) 788-4545

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

(Copy to:)

Sam Zucker

Sidley Austin LLP

1001 Page Mill Road

Palo Alto, CA 94304

Tel: (650) 565-7000

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	☒  (Do not check if a smaller reporting company)	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.  ☒

CALCULATION OF REGISTRATION FEE

Title of Securities to Be Registered	Amount to Be Registered (1)	Proposed Maximum Offering Price per Share (2)	Proposed Maximum Aggregate Offering Price (2)	Amount of Registration Fee (2)
Common Stock, $0.001 par value per share	1,192,496(3)	N/A	N/A	N/A

(1) This Post-Effective Amendment No. 1 on Form S-8 to Form S-4 Registration Statement registers 1,192,496 shares of Alpine Immune Sciences, Inc.’s common stock, $0.001 par value per share (“Common Stock”), that may be issued pursuant to awards granted under the Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan, as amended (the “Plan”). Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the “Securities Act”), this registration statement also covers an indeterminate number of shares of Common Stock that may be offered or issued by reason of stock splits, stock dividends or similar transactions.

(2) The registration fee in respect of such shares of Common Stock was previously paid at the time of the original filing of the Registration Statement on Form S-4 relating to such Common Stock.

(3) Represents shares of Common Stock subject to previously granted options under the Plan that are outstanding as of the date this registration statement is being filed.

EXPLANATORY NOTE

Alpine Immune Sciences, Inc., a Delaware corporation, formerly known as Nivalis Therapeutics, Inc. (the “Registrant,” “we,” “us” or “our”), hereby amends its Registration Statement on Form S-4 (File No. 333-218134), declared effective on June 6, 2017 (the “Form S-4”), by filing this Post-Effective Amendment No. 1 on Form S-8 to Form S-4 Registration Statement relating to 1,192,496 shares of the Registrant’s common stock issuable upon the exercise of options granted pursuant to the terms of the Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan, as amended (the “Plan”). All such shares were previously registered on the Form S-4 but will be subject to issuance pursuant to this Post-Effective Amendment No. 1 on Form S-8 to Form S-4 Registration Statement. The Form S-4, as amended by this Post-Effective Amendment No. 1 on Form S-8 to Form S-4 Registration Statement, is referred to as the “Registration Statement.”

On July 24, 2017, the Registrant completed its business combination with what was then known as Alpine Immune Sciences, Inc. (“Old Alpine”) in accordance with the terms of the Agreement and Plan of Merger and Reorganization, dated as of April 18, 2017, by and among the Registrant, Nautilus Merger Sub, Inc. (“Merger Sub”), and Old Alpine (the “Merger Agreement”), pursuant to which Merger Sub merged with and into Old Alpine, with Old Alpine surviving as a wholly owned subsidiary of the Registrant (the “Merger”). Pursuant to the Merger Agreement, each option to purchase shares of Old Alpine common stock that was outstanding and unexercised immediately prior to the effective time of the Merger under the Plan, whether or not vested, was converted into and became an option to purchase shares of Registrant common stock and the Registrant assumed the Plan.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1. Plan Information.

The Registrant has sent or given or will send or give documents containing the information required by Part I of Form S-8, as specified in Rule 428(b)(1)(i) promulgated by the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Securities Act”). In accordance with the note to Part I of Form S-8 and Rule 428 of the Securities Act, the Registrant has not filed such document(s) with the SEC, but such document(s), along with the documents incorporated by reference into this Registration Statement pursuant to Item 3 of Part II hereof, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.

Item 2. Registrant Information and Employee Plan Annual Information.

Upon written or oral request, any of the documents incorporated by reference in Item 3 of Part II of this Registration Statement (which documents are incorporated by reference in the Section 10(a) prospectus) and other documents required to be delivered to eligible participants pursuant to Rule 428(b) are available without charge by contacting:

Alpine Immune Sciences, Inc.

Attn: Chief Financial Officer

201 Elliott Avenue West, Suite 230

Seattle, WA 98119

Tel: (206) 788-4545

-1-

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

The following documents and information previously filed or to be filed by us with the SEC are incorporated by reference in this registration statement:

• our Annual Report on Form 10-K for the year ended December 31, 2016 filed with the SEC on February 13, 2017;

• our prospectus filed with the SEC on June 6, 2017 pursuant to Rule 424(b)(3) under the Securities Act, relating to the Registration Statement on Form S-4, as amended (File No. 333-218134), which contains our unaudited financial statements as of and for the three months ended March 31, 2016 and 2017 and our audited financial statements as of and for the years ended December 31, 2016 and 2015;

• our Quarterly Report on Form 10-Q for the quarter ended March 31, 2017 filed with the SEC on May 2, 2017 and our Quarterly Report on Form 10-Q for the quarter ended June 30, 2017 filed with the SEC on July 21, 2017;

• our Current Reports on Form 8-K or Form 8-K/A, as applicable, filed with the SEC on January 4, 2017, January 12, 2017, February 13, 2017, February 23, 2017, April 18, 2017, April 28, 2017, May 1, 2017, May 17, 2017, June 2, 2017, July 20, 2017, and July 25, 2017; and

• the description of our Common Stock contained in Item 1 of Form 8-A filed on June 16, 2015 (File No. 333-204127) with the SEC, including any amendment or report filed for the purpose of updating such description.

All documents filed by us pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), subsequent to the date of this Registration Statement and prior to the filing of a post-effective amendment that indicates that all securities offered have been sold or that deregisters all securities remaining unsold, shall be deemed to be incorporated by reference into this Registration Statement and to be a part hereof from the date of filing of such documents.

Notwithstanding the foregoing, information furnished under Item 2.02 or 7.01 of any Current Report on Form 8-K, including the related exhibits, is not incorporated by reference in this Registration Statement or any related prospectus.

Any statement contained herein or in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

Item 4. Description of Securities.

Not applicable.

Item 5. Interests of Named Experts and Counsel.

Not applicable.

-2-

Item 6. Indemnification of Directors and Officers.

Subsection (a) of Section 145 of the General Corporation Law of the State of Delaware (the “DGCL”) empowers a corporation to indemnify any person who was or is a party or who is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe the person’s conduct was unlawful.

Subsection (b) of Section 145 of the DGCL empowers a corporation to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person acted in any of the capacities set forth above, against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Delaware Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Delaware Court of Chancery or such other court shall deem proper.

Section 145 of the DGCL further provides that to the extent a director or officer of a corporation has been successful on the merits or otherwise in the defense of any action, suit or proceeding referred to in subsections (a) and (b) of Section 145, or in defense of any claim, issue or matter therein, such person shall be indemnified against expenses (including attorneys’ fees) actually and reasonably incurred by such person in connection therewith; the indemnification provided for by Section 145 shall not be deemed exclusive of any other rights to which the indemnified party may be entitled; and the indemnification provided for by Section 145 shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of such person’s heirs, executors and administrators. Section 145 also empowers the corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of his status as such, whether or not the corporation would have the power to indemnify such person against such liabilities under Section 145.

Section 102(b)(7) of the DGCL provides that a corporation’s certificate of incorporation may contain a provision eliminating or limiting the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, provided that such provision shall not eliminate or limit the liability of a director (i) for any breach of the director’s duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from which the director derived an improper personal benefit.

The Registrant’s Amended and Restated Certificate of Incorporation provides that, to the fullest extent permitted by the DGCL, a director of the Registrant shall not be personally liable to the Registrant or its stockholders for monetary damages for breach of fiduciary duty as director. If the DGCL is amended to authorize corporate action further eliminating or limiting the personal liability of directors, then the liability of a director of the Registrant shall be eliminated or limited to the fullest extent permitted by the DGCL as so amended. Any repeal or modification of the above provisions in the Registrant’s Amended and Restated Certificate of Incorporation shall not adversely affect any right or protection of a director of the Registrant existing at the time of, or increase the liability of any director of the Registrant with respect to any acts or omissions of such director prior to, such repeal or modification.

The Registrant’s Amended and Restated Bylaws provide that the Registrant shall indemnify and hold harmless, to the fullest extent permitted by the DGCL as it presently exists or may be amended, any director or officer of the Registrant who was or is made or is threatened to be made a party or is otherwise involved in any action, suit or proceeding, whether civil, criminal, administrative or investigative (a “Proceeding) by reason of the fact that

-3-

he or she, or a person for whom he or she is the legal representative, is or was a director or officer of the Registrant or is or was serving at the request of the Registrant as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust, enterprise or non-profit entity, including service with respect to employee benefit plans, against all liability and loss suffered and expenses (including attorneys’ fees) reasonably incurred by such person in connection with any such Proceeding. Except as otherwise provided in the Registrant’s Amended and Restated Bylaws, the Registrant shall be required to indemnify a person in connection with a Proceeding initiated by such person only if the Proceeding was authorized in the specific case by the Registrant’s board of directors.

The Registrant’s Amended and Restated Bylaws also provide that the Registrant shall have the power to indemnify and hold harmless, to the extent permitted by applicable law as it presently exists or may be amended, any employee or agent of the Registrant who was or is made or is threatened to be made a party or is otherwise involved in any Proceeding by reason of the fact that he or she, or a person for whom he or she is the legal representative, is or was an employee or agent of the Registrant or is or was serving at the request of the Registrant as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust, enterprise or non-profit entity, including service with respect to employee benefit plans, against all liability and loss suffered and expenses reasonably incurred by such person in connection with any such Proceeding. The Registrant’s Amended and Restated Bylaws further provide that the Registrant shall to the fullest extent not prohibited by applicable law pay the expenses (including attorneys’ fees) incurred by any officer or director of the Registrant, and may pay the expenses incurred by any employee or agent of the Registrant, in defending any Proceeding in advance of its final disposition; provided, however, that, to the extent required by law, such payment of expenses in advance of the final disposition of the Proceeding shall be made only upon receipt of an undertaking by the person to repay all amounts advanced if it should be ultimately determined that the person is not entitled to be indemnified under this the Registrant’s Amended and Restated Bylaws or otherwise. The Registrant’s Amended and Restated Bylaws further provide that the rights to indemnification and to prepayment of expenses provided by, or granted pursuant to, the Registrant’s Amended and Restated Bylaws shall continue notwithstanding that the person has ceased to be a director or officer of the Registrant and shall inure to the benefit of the estate, heirs, executors, administrators, legatees and distributees of such person. The Registrant’s Amended and Restated Bylaws further provide that such rights shall not be exclusive of any other rights acquired by directors and officers, including by agreement.

The Registrant has entered into indemnification agreements with each of its directors and executive officers. The Registrant also has and intends to maintain director and officer liability insurance.

Item 7. Exemption from Registration Claimed.

Not applicable.

Item 8. Exhibits.

EXHIBITS

EXHIBIT NUMBER	DESCRIPTION
4.1	Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan, as amended
4.2	Form of Option Agreement under the Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan, as amended
23.1	Consent of Independent Registered Public Accounting Firm
23.2	Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm
24.1	Power of Attorney (included on the signature page of this registration statement)

Item 9. Undertakings.

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;

-4-

(ii) To reflect in the prospectus any facts or events arising after the effective date of the 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 the 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 SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

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

provided, however, that paragraphs (1)(i) and (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 SEC by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the 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. 

(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.

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 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 the 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. 

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 SEC 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.

-5-

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, 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 Post-Effective Amendment No. 1 on Form S-8 to Form S-4 Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Seattle, State of Washington, on September 11, 2017.

ALPINE IMMUNE SCIENCES, INC.
By:	/s/ Mitchell H. Gold, M.D.
Name:	Mitchell H. Gold, M.D.
Title:	Executive Chairman and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Mitchell H. Gold, M.D. and Paul Rickey, and each of them acting individually, as his or her true and lawful attorney-in-fact, 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 (unless revoked in writing), to sign any and all amendments (including post-effective amendments thereto) to this registration statement, and to file the same, with exhibits thereto and other documents in connection therewith, with the U.S. Securities and Exchange Commission, granting to such attorney-in-fact full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as full to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that such attorney-in-fact, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment No. 1 on Form S-8 to Form S-4 Registration Statement has been signed by the following persons in the capacities and on the date indicated.

/s/ Mitchell H. Gold, M.D.
Mitchell H. Gold, M.D.	Chief Executive Officer and Executive Chairman of the Board of Directors (principal executive officer)	September 11, 2017
/s/ Paul Rickey
Paul Rickey	Senior Vice President and Chief Financial Officer (principal financial and accounting officer)	September 11, 2017
/s/ Jay Venkatesan, M.D.
Jay Venkatesan, M.D.	President and Director	September 10, 2017
/s/ James Topper, M.D., Ph.D.
James Topper, M.D., Ph.D.	Director	September 11, 2017
/s/ Robert Conway
Robert Conway	Director	September 11, 2017
/s/ Peter Thompson, M.D.
Peter Thompson, M.D.	Director	September 10, 2017
/s/ Paul Sekhri
Paul Sekhri	Director	September 10, 2017

-6-

EXHIBIT INDEX

EXHIBIT NUMBER	DESCRIPTION
4.1	Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan, as amended
4.2	Form of Option Agreement under the Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan, as amended
23.1	Consent of Independent Registered Public Accounting Firm
23.2	Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm
24.1	Power of Attorney (included on the signature page of this registration statement)

EX-4.1

Exhibit 4.1

ALPINE IMMUNE SCIENCES, INC.

AMENDED AND RESTATED 2015 STOCK PLAN

As Amended through June 9, 2016 (the “Effective Date”)

BACKGROUND

A. Alpine Immune Sciences, Inc., a Delaware corporation (the “Company”), with the approval of its board of directors and stockholders, previously adopted the Alpine Immune Sciences, Inc. 2015 Stock Plan, as amended by that certain Amendment No. 1 to the Alpine Immune Sciences, Inc. 2015 Stock Plan (together, the “Old Plan”).

B. Effective as of the Effective Date, with the approval of its board of directors and stockholders, the Company now wishes to amend and restate the Old Plan to, among other things: (i) remove the default Double-Trigger Acceleration provision described in Section 14 of the Old Plan, and (ii) increase the number of shares of Common Stock reserved for issuance under the Old Plan from 1,250,000 to 2,394,935, all by amending and restating the Old Plan in its entirety, upon the terms set forth in this Amended and Restated Alpine Immune Sciences, Inc. 2015 Stock Plan (this “Plan”).

C. It is the intention that all Shares (including related Options or Stock Purchase Rights, each as defined in the Old Plan) that were issued or sold in accordance with the Old Plan prior to the Effective Date shall continue to be governed by the Old Plan and that all Shares (including related Options or Stock Purchase Rights, each as defined in this Plan) issued or sold on or after the Effective Date will now be governed by this Plan.

PLAN

1. Purposes of the Plan. The purposes of this Alpine Immune Sciences, Inc. Amended and Restated 2015 Stock Plan (this “Plan”) are to attract and retain the best available personnel for positions of substantial responsibility, to provide additional incentive to Employees and Consultants, and to promote the success of the Company’s business. Options granted under the Plan may be Incentive Stock Options or Nonstatutory Stock Options, as determined by the Administrator at the time of grant of an Option and subject to the applicable provisions of Section 422 of the Code and the regulations promulgated thereunder. Stock purchase rights may also be granted under the Plan. The Company intends that the Plan comply with Section 409A of the Code (including any amendments or replacements of such section), and the Plan shall be so construed.

2. Definitions. As used herein, the following definitions shall apply:

(a) “Administrator” means the Board or its Committee appointed pursuant to Section 4 of the Plan.

(b) “Affiliate” means an entity other than a Subsidiary (as defined below) which, together with the Company, is under common control of a third person or entity.

(c) “Applicable Laws” means the legal requirements relating to the administration of stock option and restricted stock purchase plans under applicable U.S. state corporate laws, U.S. federal and applicable state securities laws, the Code, any Stock Exchange rules or regulations, and the applicable laws of any other country or jurisdiction where Options or Stock Purchase Rights are granted under the Plan, as such laws, rules, regulations, and requirements shall be in place from time to time.

(d) “Board” means the board of directors of the Company.

(e) “Cause” for termination of a Participant’s Continuous Service Status will exist if the Participant is terminated for any of the following reasons: (i) Participant’s willful failure substantially to perform his or her duties and responsibilities to the Company or deliberate violation of a Company policy; (ii) Participant’s commission of any act of fraud, embezzlement, dishonesty, or any other willful misconduct that has caused or is reasonably expected to result in material injury to the Company; (iii) unauthorized use or disclosure by Participant of any proprietary information or trade secrets of the Company or any other party to whom the Participant owes an obligation of nondisclosure as a result of his or her relationship with the Company; or (iv) Participant’s willful breach of any of his or her obligations under any written agreement or covenant with the Company. The determination as to whether a Participant is being terminated for Cause shall be made in good faith by the Company and shall be final and binding on the Participant. The foregoing definition does not in any way limit the Company’s ability to terminate a Participant’s employment or consulting relationship at any time as provided in Section 5(d) below, and the term “Company” will be interpreted to include any Subsidiary, Parent, Affiliate, or successor thereto, if appropriate.

(f) “Change of Control” means a sale of all or substantially all of the Company’s assets, or any stock sale, merger, or consolidation of the Company with or into another corporation or business entity other than a stock sale, merger, or consolidation in which the holders of more than fifty percent (50%) of the shares of capital stock of the Company outstanding immediately prior to such transaction continue to hold (either by the voting securities remaining outstanding or by their being converted into voting securities of the surviving entity) more than fifty percent (50%) of the total voting power represented by the voting securities of the Company, or such surviving entity, outstanding immediately after such transaction; provided, however, that a bona fide equity financing by the Company will not be deemed to be a Change of Control.

(g) “Code” means the Internal Revenue Code of 1986, as amended from time to time.

(h) “Committee” means one or more committees or subcommittees of the Board appointed by the Board to administer the Plan in accordance with Section 4 below.

(i) “Common Stock” means the Common Stock of the Company.

(j) “Company” means Alpine Immune Sciences, Inc., a Delaware corporation.

(k) “Consultant” means any person, including an advisor, who is engaged by the Company or any Parent, Subsidiary, or Affiliate to render services and is compensated for such services, and any Director of the Company whether compensated for such services or not.

(l) “Continuous Service Status” means the absence of any interruption or termination of service as an Employee or Consultant. Continuous Service Status as an Employee or Consultant shall not be considered interrupted in the case of: (i) sick leave; (ii) military leave; (iii) any other leave of absence approved by the Administrator; provided, however, that such leave is for a period of not more than ninety (90) days, unless reemployment upon the expiration of such leave is guaranteed by contract or statute, or unless provided otherwise pursuant to Company policy adopted from time to time; or (iv) in the case of transfers between locations of the Company or between the Company, its Parents, Subsidiaries, Affiliates, or their respective successors. A change in status from an Employee to a Consultant or from a Consultant to an Employee will not constitute an interruption of Continuous Service Status.

(m) “Corporate Transaction” means a sale of all or substantially all of the Company’s assets, or a merger, consolidation, or other capital reorganization of the Company with or into another corporation or business entity and includes a Change of Control.

(n) “Director” means a member of the Board.

(o) “Employee” means any person employed by the Company or any Parent, Subsidiary, or Affiliate, with the status of employment determined based upon such factors as are deemed appropriate by the Administrator in its discretion, subject to any requirements of the Code or the Applicable Laws. The payment by the Company of a director’s fee to a Director shall not be sufficient to constitute “employment” of such Director by the Company.

(p) “Exchange Act” means the Securities Exchange Act of 1934, as amended from time to time.

(q) “Fair Market Value” means, as of any date, the fair market value of the Common Stock, as determined by the Administrator in good faith on such basis as it deems appropriate and applied consistently with respect to Participants, and subject to compliance with Section 409A of the Code. Whenever possible, the determination of Fair Market Value shall be based upon the closing price for the Shares as reported in The Wall Street Journal for the applicable date.

(r) “Incentive Stock Option” means an Option intended to qualify as an incentive stock option within the meaning of Section 422 of the Code, as designated in the applicable Option Agreement.

(s) “Involuntary Termination” means termination of a Participant’s Continuous Service Status under the following circumstances: (i) termination without Cause by the Company or a Subsidiary, Parent, Affiliate or successor thereto, as appropriate; or (ii) voluntary termination by the Participant within thirty (30) days following (A) a material reduction in the Participant’s job responsibilities, provided that neither a mere change in title alone nor reassignment following a Change of Control to a position that is substantially similar to the position held prior to the Change of Control shall constitute a material reduction in job responsibilities; (B) relocation by the Company or a Subsidiary, Parent, Affiliate, or successor thereto, as appropriate, of the Participant’s work site to a facility or location more than thirty (30) miles from the Participant’s principal work site for the Company at the time of the Change of Control; or (C) a reduction in Participant’s then-current base salary by at least five percent (5%); provided, however, that an across-the-board reduction in the salary level of all other employees or consultants in positions similar to the Participant’s by the same percentage amount as part of a general salary level reduction shall not constitute such a salary reduction.

(t) “Listed Security” means any security of the Company that is listed or approved for listing on a national securities exchange or designated or approved for designation as a national market system security on an interdealer quotation system by the National Association of Securities Dealers, Inc.

(u) “Named Executive” means any individual who, on the last day of the Company’s fiscal year, is the chief executive officer of the Company (or is acting in such capacity) or among the four most highly compensated officers of the Company (other than the chief executive officer). Such officer status shall be determined pursuant to the executive compensation disclosure rules under the Exchange Act.

(v) “Nonstatutory Stock Option” means an Option not intended to qualify as an Incentive Stock Option, as designated in the applicable Option Agreement.

(w) “Option” means a stock option granted pursuant to the Plan.

(x) “Option Agreement” means a written document, the form(s) of which shall be approved from time to time by the Administrator, reflecting the terms of an Option granted under the Plan and includes any documents attached to or incorporated into such Option Agreement, including, but not limited to, a notice of stock option grant and a form of exercise notice.

(y) “Option Exchange Program” means a program approved by the Administrator whereby outstanding Options are exchanged for Options with a lower exercise price or are amended to decrease the exercise price as a result of a decline in the Fair Market Value of the Common Stock.

(z) “Optioned Stock” means the Common Stock subject to an Option.

(aa) “Optionee” means an Employee or Consultant who receives an Option.

(bb) “Parent” means a “parent corporation,” whether now or hereafter existing, as defined in Section 424(e) of the Code, or any successor provision.

(cc) “Participant” means any holder of one or more Options or Stock Purchase Rights, or the Shares issuable or issued upon exercise of such awards, under the Plan.

(dd) “Plan” means this Alpine Immune Sciences, Inc. Amended and Restated 2015 Stock Plan.

(ee) “Reporting Person” means an officer, Director, or greater than ten percent (10%) stockholder of the Company within the meaning of Rule 16a-2 under the Exchange Act, who is required to file reports pursuant to Rule 16a-3 under the Exchange Act.

(ff) “Restricted Stock” means Shares of Common Stock acquired pursuant to a grant of a Stock Purchase Right under Section 10 below.

(gg) “Restricted Stock Purchase Agreement” means a written document, the form(s) of which shall be approved from time to time by the Administrator, reflecting the terms of a Stock Purchase Right granted under the Plan and includes any documents attached to such agreement.

(hh) “Rule 16b-3” means Rule 16b-3 promulgated under the Exchange Act, as amended from time to time, or any successor provision.

(ii) “Share” means a share of the Common Stock, as adjusted in accordance with Section 13 of the Plan.

(jj) “Stock Exchange” means any stock exchange or consolidated stock price reporting system on which prices for the Common Stock are quoted at any given time.

(kk) “Stock Purchase Right” means the right to purchase Common Stock pursuant to Section 10 below.

(ll) “Subsidiary” means a “subsidiary corporation,” whether now or hereafter existing, as defined in Section 424(f) of the Code, or any successor provision.

(mm) “Ten Percent Holder” means a person who owns stock representing more than ten percent (10%) of the voting power of all classes of stock of the Company or any Parent or Subsidiary.

3. Stock Subject to the Plan. Subject to the provisions of Section 13 of the Plan, the maximum aggregate number of Shares that may be sold under the Plan is two million three hundred ninety-four thousand nine hundred thirty-five (2,394,935) Shares of Common Stock. The Shares may be authorized, but unissued, or reacquired Common Stock. If an award should expire or become unexercisable for any reason without having been exercised in full, or is surrendered pursuant to an Option Exchange Program, the unpurchased Shares that were subject thereto shall, unless the Plan shall have been terminated, become available for future grant under the Plan. In addition, any Shares of Common Stock which are retained by the Company upon exercise of an award in order to satisfy the exercise or purchase price for such award or any withholding taxes due with respect to such exercise or purchase shall be treated as not issued and shall continue to be available under the Plan. Shares issued under the Plan and later repurchased by the Company pursuant to any repurchase right which the Company may have shall not be available for future grant under the Plan.

4. Administration of the Plan.

(a) General. The Plan shall be administered by the Board or a Committee, or a combination thereof, as determined by the Board. The Plan may be administered by different administrative bodies with respect to different classes of Participants and, if permitted by the Applicable Laws, the Board may authorize one or more officers to make awards under the Plan.

(b) Committee Composition. If a Committee has been appointed pursuant to this Section 4, such Committee shall continue to serve in its designated capacity until otherwise directed by the Board. From time to time the Board may increase the size of any Committee and appoint additional members thereof, remove members (with or without cause) and appoint new members in substitution therefor, fill vacancies (however caused) and remove all members of a Committee and thereafter directly administer the Plan, all to the extent permitted by the Applicable Laws and, in the case of a Committee administering the Plan in accordance with the requirements of Rule 16b-3 or Section 162(m) of the Code, to the extent permitted or required by such provisions.

(c) Powers of the Administrator. Subject to the provisions of the Plan and in the case of a Committee, the specific duties delegated by the Board to such Committee, the Administrator shall have the authority, in its discretion:

(i) to determine the Fair Market Value of the Common Stock, in accordance with Section 2(q) of the Plan; provided, however, that such determination shall be applied consistently with respect to Participants under the Plan;

(ii) to select the Employees and Consultants to whom Options and Stock Purchase Rights may from time to time be granted;

(iii) to determine whether and to what extent Options and Stock Purchase Rights are granted;

(iv) to determine the number of Shares of Common Stock to be covered by each award granted;

(v) to approve the form(s) of agreement(s) used under the Plan;

(vi) to determine the terms and conditions, not inconsistent with the terms of the Plan, of any award granted hereunder, which terms and conditions include but are not limited to the exercise or purchase price, the time or times when awards may be exercised (which may be based on performance criteria), any vesting acceleration or waiver of forfeiture restrictions, and any restriction or limitation regarding any Option, Optioned Stock, Stock Purchase Right, or Restricted Stock, based in each case on such factors as the Administrator, in its sole discretion, shall determine;

(vii) to determine whether and under what circumstances an Option may be settled in cash under Section 9 (c) instead of Common Stock;

(viii) to implement an Option Exchange Program on such terms and conditions as the Administrator in its discretion deems appropriate; provided, however, that no amendment or adjustment to an Option that would materially and adversely affect the rights of any Optionee shall be made without the prior written consent of the Optionee;

(ix) to adjust the vesting of an Option held by an Employee or Consultant as a result of a change in the terms or conditions under which such person is providing services to the Company;

(x) to construe and interpret the terms of the Plan and awards granted under the Plan, which constructions, interpretations, and decisions shall be final and binding on all Participants;

(xi) to make any adjustment or amendment to the Plan or to an outstanding award with or without a Participant’s consent if such adjustment or amendment is necessary to avoid the Company’s incurring adverse accounting charges; and

(xii) in order to fulfill the purposes of the Plan and without amending the Plan, to modify grants of Options or Stock Purchase Rights to Participants who are foreign nationals or employed outside of the United States in order to recognize differences in local law, tax policies, or customs.

5. Eligibility.

(a) Recipients of Grants. Nonstatutory Stock Options and Stock Purchase Rights may be granted to Employees and Consultants. Incentive Stock Options may be granted only to Employees; provided, however, that Employees of Affiliates shall not be eligible to receive Incentive Stock Options.

(b) Type of Option. Each Option shall be designated in the Option Agreement as either an Incentive Stock Option or a Nonstatutory Stock Option.

(c) ISO $100,000 Limitation. Notwithstanding any designation under Section 5(b), to the extent that the aggregate Fair Market Value of Shares with respect to which Options designated as Incentive Stock Options are exercisable for the first time by any Optionee during any calendar year (under all plans of the Company or any Parent or Subsidiary) exceeds One Hundred Thousand Dollars ($100,000), such excess Options shall be treated as Nonstatutory Stock Options. For purposes of this Section 5(c), Incentive Stock Options shall be taken into account in the order in which they were granted, and the Fair Market Value of the Shares subject to an Incentive Stock Option shall be determined as of the date of the grant of such Option.

(d) No Employment Rights. The Plan shall not confer upon any Participant any right with respect to continuation of an employment or consulting relationship with the Company, nor shall it interfere in any way with such Participant’s right or the Company’s right to terminate his or her employment or consulting relationship at any time, with or without Cause.

6. Term of Plan. The Plan shall become effective upon its adoption by the Board of Directors. It shall continue in effect for a term of ten (10) years unless sooner terminated under Section 15 of the Plan.

7. Term of Option. The term of each Option shall be the term stated in the Option Agreement; provided, however, that the term shall be no more than ten (10) years from the date of grant thereof or such shorter term as may be provided in the Option Agreement; and provided further however, that, in the case of an Incentive Stock Option granted to a person who at the time of such grant is a Ten Percent Holder, the term of the Option shall be five (5) years from the date of grant thereof or such shorter term as may be provided in the Option Agreement.

8. Option Exercise Price and Consideration.

(a) Exercise Price. The per Share exercise price for the Shares to be issued pursuant to exercise of an Option shall be such price as is determined by the Administrator, subject to compliance with Section 409A of the Code, and set forth in the Option Agreement, but shall be subject to the following:

(i) In the case of an Incentive Stock Option

(A) granted to an Employee who at the time of grant is a Ten Percent Holder, the per Share exercise price shall be no less than one hundred ten percent (110%) of the Fair Market Value per Share on the date of grant; or

(B) granted to any other Employee, the per Share exercise price shall be no less than one hundred percent (100%) of the Fair Market Value per Share on the date of grant.

(ii) In the case of a Nonstatutory Stock Option

(A) granted prior to the date, if any, on which the Common Stock becomes a Listed Security to a person who is at the time of grant is a Ten Percent Holder, the per Share exercise price shall be no less than one hundred ten percent (110%) of the Fair Market Value per Share on the date of grant if required by the Applicable Laws and, if not so required, shall be such price as is determined by the Administrator;

(B) granted prior to the date, if any, on which the Common Stock becomes a Listed Security to any other eligible person, the per Share exercise price shall be no less than the Fair Market Value per Share on the date of grant if required by the Applicable Laws and, if not so required, shall be such price as is determined by the Administrator.

(C) granted on or after the date, if any, on which the Common Stock becomes a Listed Security to any eligible person, the per share Exercise Price shall be such price as determined by the Administrator provided that if such eligible person is, at the time of the grant of such Option, a Named Executive of the Company, the per share Exercise Price shall be no less than one hundred percent (100%) of the Fair Market Value on the date of grant if such Option is intended to qualify as performance-based compensation under Section 162(m) of the Code.

(iii) Notwithstanding the foregoing, Options may be granted with a per Share exercise price other than as required above pursuant to a merger or other corporate transaction.

(b) Permissible Consideration. The consideration to be paid for the Shares to be issued upon exercise of an Option, including the method of payment, shall be determined by the Administrator (and, in the case of an Incentive Stock Option, shall be determined at the time of grant) and may consist entirely of (1) cash; (2) check; (3) delivery of Optionee’s full recourse promissory note with such interest, security, and redemption provisions as the Administrator determines to be appropriate; (4) cancellation of indebtedness; (5) other Shares that have a Fair Market Value on the date of surrender equal to the aggregate exercise price of the Shares as to which the Option is exercised; provided, however, that in the case of Shares acquired, directly or indirectly, from the Company, such Shares must have been owned by the Optionee for more than six (6) months on the date of surrender (or such other period as may be required to avoid the Company’s incurring an adverse accounting charge); (6) delivery of a properly executed exercise notice together with such other documentation as the Administrator and a securities broker approved by the Company shall require to effect exercise of the Option and prompt delivery to the Company of the sale or loan proceeds required to pay the exercise price and any applicable withholding taxes; or (7) any combination of the foregoing methods of payment. In making its determination as to the type of consideration to accept, the Administrator shall consider if acceptance of such consideration may be reasonably expected to benefit the Company and the Administrator may, in its sole discretion, refuse to accept a particular form of consideration at the time of any Option exercise.

9. Exercise of Option.

(a) General.

(i) Exercisability. Any Option granted hereunder shall be exercisable at such times and under such conditions as determined by the Administrator, consistent with the term of the Plan and reflected in the Option Agreement, including vesting requirements and/or performance criteria with respect to the Company and/or the Optionee; provided, however, that, if required by the Applicable Laws, any Option granted prior to the date, if any, upon which the Common Stock becomes a Listed Security shall become exercisable at the rate of at least twenty percent (20%) per year over five (5) years from the date the Option is granted. In the event that any of the Shares issued upon exercise of an Option (which exercise occurs prior to the date, if any, upon which the Common Stock becomes a Listed Security) should be subject to a right of repurchase in the Company’s favor, such repurchase right shall, if required by the Applicable Laws, lapse at the rate of at least twenty percent (20%) per year over five (5) years from the date the Option is granted. Notwithstanding the above, in the case of an Option granted to an officer, Director, or Consultant of the Company or any Parent, Subsidiary, or Affiliate of the Company, the Option may become fully exercisable, or a repurchase right, if any, in favor of the Company shall lapse, at any time or during any period established by the Administrator. The Administrator shall have the discretion to determine whether and to what extent the vesting of Options shall be tolled during any unpaid leave of absence; provided, however, that in the absence of such determination, vesting of Options shall be tolled during any such leave.

(ii) Minimum Exercise Requirements. An Option may not be exercised for a fraction of a Share. The Administrator may require that an Option be exercised as to a minimum number of Shares, provided that such requirement shall not prevent an Optionee from exercising the full number of Shares as to which the Option is then exercisable.

(iii) Procedures for and Results of Exercise. An Option shall be deemed exercised when written notice of such exercise has been given to the Company in accordance with the terms of the Option by the person entitled to exercise the Option and the Company has received full

payment for the Shares with respect to which the Option is exercised. Full payment may, as authorized by the Administrator, consist of any consideration and method of payment allowable under Section 8(b) of the Plan; provided, however, that the Administrator may, in its sole discretion, refuse to accept any form of consideration at the time of any Option exercise.

Exercise of an Option in any manner shall result in a decrease in the number of Shares that thereafter may be available, both for purposes of the Plan and for sale under the Option, by the number of Shares as to which the Option is exercised.

(iv) Rights as Stockholder. Until the issuance of the Shares (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company), no right to vote or receive dividends or any other rights as a stockholder shall exist with respect to the Optioned Stock, notwithstanding the exercise of the Option. No adjustment will be made for a dividend or other right for which the record date is prior to the date the stock certificate is issued, except as provided in Section 13 of the Plan.

(b) Termination of Employment or Consulting Relationship. Upon termination of an Optionee’s employment or consulting relationship with the Company, the Company will have the right, in its sole discretion, to repurchase an Optionee’s vested and exercised Shares by providing Optionee written notice within six (6) months of the expiration of such Optionee’s ability to exercise an Option as set forth in Sections 9(b)(i-iii) below (the “Repurchase Right”). If the Company exercises its Repurchase Right, it will pay such Optionee a price equal to the Fair Market Value of his or her vested and exercised Shares as of the date of such Optionee’s termination of employment or consulting relationship with the Company (the “Repurchase Price”). The Company will pay the Repurchase Price to the Optionee in twenty-four (24) equal monthly installments beginning on the date the Company exercises its Repurchase Right. Except as otherwise set forth in this Section 9(b), the Administrator shall establish and set forth in the applicable Option Agreement the terms and conditions upon which an Option shall remain exercisable, if at all, following termination of an Optionee’s Continuous Service Status, which provisions may be waived or modified by the Administrator at any time. To the extent that the Optionee is not entitled to exercise an Option at the date of his or her termination of Continuous Service Status, or if the Optionee (or other person entitled to exercise the Option) does not exercise the Option to the extent so entitled within the time specified in the Option Agreement or below (as applicable), the Option shall terminate and the Optioned Stock underlying the unexercised portion of the Option shall revert to the Plan. In no event may any Option be exercised after the expiration of the Option term as set forth in the Option Agreement (and subject to Section 7).

The following provisions (1) shall apply to the extent an Option Agreement does not specify the terms and conditions upon which an Option shall terminate upon termination of an Optionee’s Continuous Service Status, and (2) establish the minimum post-termination exercise periods that may be set forth in an Option Agreement:

(i) Termination other than Upon Disability or Death or for Cause. In the event of termination of an Optionee’s Continuous Service Status, such Optionee may exercise an Option for ninety (90) days following such termination to the extent the Optionee was entitled to exercise it at the date of such termination. No termination shall be deemed to occur and this Section 9(b)(i) shall not apply if (i) the Optionee is a Consultant who becomes an Employee, or (ii) the Optionee is an Employee who becomes a Consultant.

(ii) Disability of Optionee. In the event of termination of an Optionee’s Continuous Service Status as a result of his or her disability (including a disability within the meaning of Section 22(e)(3) of the Code), such Optionee may exercise an Option at any time within six (6) months following such termination to the extent the Optionee was entitled to exercise it at the date of such termination.

(iii) Death of Optionee. In the event of the death of an Optionee during the period of Continuous Service Status since the date of grant of the Option, or within thirty (30) days following termination of Optionee’s Continuous Service Status, the Option may be exercised by Optionee’s estate or by a person who acquired the right to exercise the Option by bequest or inheritance at any time within twelve (12) months following the date of death, but only to the extent of the right to exercise that had accrued at the date of death or, if earlier, the date the Optionee’s Continuous Service Status terminated.

(c) Buyout Provisions. The Administrator may at any time offer to buy out for a payment in cash or Shares an Option previously granted under the Plan based on such terms and conditions as the Administrator shall establish and communicate to the Optionee at the time that such offer is made.

10. Stock Purchase Rights.

(a) Rights to Purchase. When the Administrator determines that it will offer Stock Purchase Rights under the Plan, it shall advise the offeree in writing of the terms, conditions, and restrictions related to the offer, including the number of Shares that such person shall be entitled to purchase, the price to be paid, and the time within which such person must accept such offer. In the case of a Stock Purchase Right granted prior to the date, if any, on which the Common Stock becomes a Listed Security and if required by the Applicable Laws at that time, the purchase price of Shares subject to such Stock Purchase Rights shall not be less than one hundred percent (100%) of the Fair Market Value of the Shares as of the date of the offer. If the Applicable Laws do not impose the requirements set forth in the preceding sentence and with respect to any Stock Purchase Rights granted after the date, if any, on which the Common Stock becomes a Listed Security, the purchase price of Shares subject to Stock Purchase Rights shall be as determined by the Administrator. The offer to purchase Shares subject to Stock Purchase Rights shall be accepted by execution of a Restricted Stock Purchase Agreement in the form determined by the Administrator.

(b) Repurchase Option. Unless the Administrator determines otherwise, the Restricted Stock Purchase Agreement shall grant the Company a repurchase option exercisable upon the voluntary or involuntary termination of the purchaser’s employment with the Company for any reason (including death or disability). The purchase price for Shares repurchased pursuant to the Restricted Stock Purchase Agreement shall be the original purchase price paid by the purchaser and may be paid by cancellation of any indebtedness of the purchaser to the Company. The repurchase option shall lapse at such rate as the Administrator may determine, provided that with respect to a Stock Purchase Right granted prior to the date, if any, on which the Common Stock becomes a Listed Security to a purchaser who is not an officer, Director or Consultant of the Company or of any Parent or Subsidiary of the Company, it shall lapse at a minimum rate of twenty percent (20%) per year if required by the Applicable Laws.

(c) Other Provisions. The Restricted Stock Purchase Agreement shall contain such other terms, provisions, and conditions not inconsistent with the Plan as may be determined by the Administrator in its sole discretion. In addition, the provisions of Restricted Stock Purchase Agreements need not be the same with respect to each purchaser.

(d) Rights as a Stockholder. Once the Stock Purchase Right is exercised, the purchaser shall have the rights equivalent to those of a stockholder, and shall be a stockholder when his or

her purchase is entered upon the records of the duly authorized transfer agent of the Company. No adjustment will be made for a dividend or other right for which the record date is prior to the date the Stock Purchase Right is exercised, except as provided in Section 13 of the Plan.

11. Taxes.

(a) As a condition of the exercise of an Option or Stock Purchase Right granted under the Plan, the Participant (or in the case of the Participant’s death, the person exercising the Option or Stock Purchase Right) shall make such arrangements as the Administrator may require for the satisfaction of any applicable federal, state, local or foreign withholding tax obligations that may arise in connection with the exercise of the Option or Stock Purchase Right and the issuance of Shares. The Company shall not be required to issue any Shares under the Plan until such obligations are satisfied. If the Administrator allows the withholding or surrender of Shares to satisfy a Participant’s tax withholding obligations under this Section 11 (whether pursuant to Section 11(c), (d) or (e), or otherwise), the Administrator shall not allow Shares to be withheld in an amount that exceeds the minimum statutory withholding rates for federal and state tax purposes, including payroll taxes.

(b) In the case of an Employee and in the absence of any other arrangement, the Employee shall be deemed to have directed the Company to withhold or collect from his or her compensation an amount sufficient to satisfy such tax obligations from the next payroll payment otherwise payable after the date of an exercise of the Option or Stock Purchase Right.

(c) This Section 11(c) shall apply only after the date, if any, upon which the Common Stock becomes a Listed Security. In the case of Participant other than an Employee (or in the case of an Employee where the next payroll payment is not sufficient to satisfy such tax obligations, with respect to any remaining tax obligations), in the absence of any other arrangement and to the extent permitted under the Applicable Laws, the Participant shall be deemed to have elected to have the Company withhold from the Shares to be issued upon exercise of the Option or Stock Purchase Right that number of Shares having a Fair Market Value determined as of the applicable Tax Date (as defined below) equal to the amount required to be withheld. For purposes of this Section 11, the Fair Market Value of the Shares to be withheld shall be determined on the date that the amount of tax to be withheld is to be determined under the Applicable Laws (the “Tax Date”).

(d) If permitted by the Administrator, in its discretion, a Participant may satisfy his or her tax withholding obligations upon exercise of an Option or Stock Purchase Right by surrendering to the Company Shares that have a Fair Market Value determined as of the applicable Tax Date equal to the amount required to be withheld. In the case of shares previously acquired from the Company that are surrendered under this Section 11(d), such Shares must have been owned by the Participant for more than six (6) months on the date of surrender (or such other period of time as is required for the Company to avoid adverse accounting charges).

(e) Any election or deemed election by a Participant to have Shares withheld to satisfy tax withholding obligations under Section 11(c) or (d) above shall be irrevocable as to the particular Shares as to which the election is made and shall be subject to the consent or disapproval of the Administrator. Any election by a Participant under Section 11(d) above must be made on or prior to the applicable Tax Date.

(f) In the event an election to have Shares withheld is made by a Participant and the Tax Date is deferred under Section 83 of the Code because no election is filed under Section 83(b) of the Code, the Participant shall receive the full number of Shares with respect to which the Option or Stock Purchase Right is exercised but such Participant shall be unconditionally obligated to tender back to the Company the proper number of Shares on the Tax Date.

12. Non-Transferability of Options and Stock Purchase Rights.

(a) General. Except as set forth in this Section 12, Options and Stock Purchase Rights may not be sold, pledged, assigned, hypothecated, transferred, or disposed of in any manner other than by will or by the laws of descent or distribution. The designation of a beneficiary by an Optionee will not constitute a transfer. An Option or Stock Purchase Right may be exercised, during the lifetime of the holder of an Option or Stock Purchase Right, only by such holder or a transferee permitted by this Section 12.

(b) Limited Transferability Rights. Notwithstanding anything else in this Section 12, prior to the date, if any, on which the Common Stock becomes a Listed Security, the Administrator may in its discretion grant Nonstatutory Stock Options that may be transferred by instrument to an inter vivos or testamentary trust in which the Options are to be passed to beneficiaries upon the death of the trustor (settlor) or by gift to “Immediate Family” (as defined below), on such terms and conditions as the Administrator deems appropriate. Following the date, if any, on which the Common Stock becomes a Listed Security, the Administrator may in its discretion grant transferable Nonstatutory Stock Options pursuant to Option Agreements specifying the manner in which such Nonstatutory Stock Options are transferable. “Immediate Family” means any child, stepchild, grandchild, parent, stepparent, grandparent, spouse, sibling, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or sister-in-law, and shall include adoptive relationships.

13. Adjustments Upon Changes in Capitalization, Merger or Certain Other Transactions.

(a) Changes in Capitalization. Subject to any required action by the stockholders of the Company, the number of Shares of Common Stock covered by each outstanding Option or Stock Purchase Right, and the number of Shares of Common Stock that have been authorized for issuance under the Plan but as to which no Options or Stock Purchase Rights have yet been granted or that have been returned to the Plan upon cancellation or expiration of an Option or Stock Purchase Right, as well as the price per Share of Common Stock covered by each such outstanding Option or Stock Purchase Right, shall be proportionately adjusted for any increase or decrease in the number of issued Shares of Common Stock resulting from a stock split, reverse stock split, stock dividend, combination, recapitalization, or reclassification of the Common Stock, or any other increase or decrease in the number of issued Shares of Common Stock effected without receipt of consideration by the Company; provided, however, that conversion of any convertible securities of the Company shall not be deemed to have been “effected without receipt of consideration.” Such adjustment shall be made by the Administrator, whose determination in that respect shall be final, binding, and conclusive. Except as expressly provided herein, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no adjustment by reason thereof shall be made with respect to, the number or price of Shares of Common Stock subject to an Option or Stock Purchase Right.

(b) Dissolution or Liquidation. In the event of the dissolution or liquidation of the Company, each Option and Stock Purchase Right will terminate immediately prior to the consummation of such action, unless otherwise determined by the Administrator.

(c) Corporate Transaction. In the event of a Corporate Transaction, outstanding Options and Shares acquired under the Plan shall be subject to the agreement of the Corporate Transaction, which need not treat all outstanding Options in an identical manner. Such agreement,

without the Optionees’ consent, may dispose of Options that are not exercisable as of the effective date of such Corporate Transaction in any manner permitted by applicable law, including (without limitation) the cancellation of such Options without the payment of any consideration. Such agreement, without the Optionees’ consent, shall provide for one or more of the following with respect to Options that are exercisable as of the effective date of such Corporate Transaction.

(i) The continuation of such Options by the Company (if the Company is the surviving corporation).

(ii) The assumption of such Options by the surviving corporation or its parent in a manner that complies with Section 424(a) of the Code (whether or not such Options are Incentive Stock Options).

(iii) The substitution by the surviving corporation or its parent of new options for such Options in a manner that complies with Section 424(a) of the code (whether or not such Options are Incentive Stock Options).

(iv) The cancellation of such Options and a payment to the Optionees equal to the excess of (A) the Fair Market Value of the Shares subject to such Options as of the effective date of such Corporate Transaction over (B) their Exercise Price. Such payment shall be made in the form of cash, cash equivalents, or securities of the surviving corporation or its parent with a Fair Market Value equal to the required amount.

(v) The cancellation of such Options.

With the consent of the Administrator, or if appropriate, the consent of the Company’s successor entity, Options and Shares acquired under the Plan may be subject to additional acceleration of vesting and exercisability upon or after a Corporate Transaction as may be provided in any Stock Option Agreement (including in any notice of stock option grant), Restricted Stock Purchase Agreement, or as may be provided in any other written agreement between the Company or any or successor thereto, if appropriate, but in the absence of such provision, no such acceleration shall occur. Any exercise of such Options prior to the closing date of such Corporate Transaction may be contingent on the closing of such Corporate Transaction.

(d) Certain Distributions. In the event of any distribution to the Company’s stockholders of securities of any other entity or other assets (other than dividends payable in cash or stock of the Company) without receipt of consideration by the Company, the Administrator may, in its discretion, appropriately adjust the price per Share of Common Stock covered by each outstanding Option or Stock Purchase Right to reflect the effect of such distribution.

14. Time of Granting Options and Stock Purchase Rights. The date of grant of an Option or Stock Purchase Right shall, for all purposes, be the date on which the Administrator makes the determination granting such Option or Stock Purchase Right, or such other date as is determined by the Administrator; provided, however, that in the case of any Incentive Stock Option, the grant date shall be the later of the date on which the Administrator makes the determination granting such Incentive Stock Option or the date of commencement of the Optionee’s employment relationship with the Company. Notice of the determination shall be given to each Employee or Consultant to whom an Option or Stock Purchase Right is so granted within a reasonable time after the date of such grant.

15. Amendment and Termination of the Plan.

(a) Authority to Amend or Terminate. The Board may at any time amend, alter, suspend or discontinue the Plan, but no amendment, alteration, suspension or discontinuation (other than an adjustment pursuant to Section 13 above) shall be made that would materially and adversely affect the rights of any Optionee or holder of Stock Purchase Rights under any outstanding grant, without his or her consent. In addition, to the extent necessary and desirable to comply with the Applicable Laws, the Company shall obtain stockholder approval of any Plan amendment in such a manner and to such a degree as required.

(b) Effect of Amendment or Termination. No amendment or termination of the Plan shall materially and adversely affect Options or Stock Purchase Rights already granted, unless mutually agreed otherwise between the Optionee or holder of the Stock Purchase Rights and the Administrator, which agreement must be in writing and signed by the Optionee or holder and the Company.

(c) Accounting Issues. Notwithstanding anything else to the contrary in this Section 15, the Administrator may at any time amend or adjust the Plan or an outstanding award issued under the Plan without the consent of the affected Participant(s) if such amendment or adjustment is necessary to avoid the Company’s incurring adverse accounting charges.

16. Conditions Upon Issuance of Shares. Notwithstanding any other provision of the Plan or any agreement entered into by the Company pursuant to the Plan, the Company shall not be obligated, and shall have no liability for failure, to issue or deliver any Shares under the Plan unless such issuance or delivery would comply with the Applicable Laws, with such compliance determined by the Company in consultation with its legal counsel. As a condition to the exercise of an Option or Stock Purchase Right, the Company may require the person exercising the award to represent and warrant at the time of any such exercise that the Shares are being purchased only for investment and without any present intention to sell or distribute such Shares if, in the opinion of counsel for the Company, such a representation is required by law.

17. Reservation of Shares. The Company, during the term of this Plan, will at all times reserve and keep available such number of Shares as shall be sufficient to satisfy the requirements of the Plan.

18. Agreements. Options and Stock Purchase Rights shall be evidenced by Option Agreements and Restricted Stock Purchase Agreements, respectively, in such form(s) as the Administrator shall from time to time approve.

19. Stockholder Approval. If required by the Applicable Laws, continuance of the Plan shall be subject to approval by the stockholders of the Company within twelve (12) months before or after the date the Plan is adopted. Such stockholder approval shall be obtained in the manner and to the degree required under the Applicable Laws.

20. Information and Documents to Optionees and Purchasers. Prior to the date, if any, upon which the Common Stock becomes a Listed Security and if required by the Applicable Laws, the Company shall provide financial statements at least annually to each Optionee and to each individual who acquired Shares pursuant to the Plan, during the period such Optionee or purchaser has one or more Options or Stock Purchase Rights outstanding, and in the case of an individual who acquired Shares pursuant to the Plan, during the period such individual owns such Shares. The Company shall not be required to provide such information if the issuance of Options or Stock Purchase Rights under the Plan is limited to key employees whose duties in connection with the Company assure their access to equivalent information.

AMENDMENT NO. 1 TO THE ALPINE IMMUNE SCIENCES, INC.

AMENDED AND RESTATED 2015 STOCK PLAN

This Amendment No. 1 to the Alpine Immune Sciences, Inc. Amended and Restated 2015 Stock Plan (this “Amendment”) is made effective as of March 29, 2017 by Alpine Immune Sciences, Inc., a Delaware corporation (the “Company”) to amend that certain Alpine Immune Sciences, Inc. Amended and Restated 2015 Stock Plan (the “Plan”). Capitalized terms used herein and not defined shall have the meanings given to them in the Plan.

RECITALS

WHEREAS: The board of directors (the “Board”) and stockholders (the “Stockholders”) of the Company, have approved the existing Plan; and

WHEREAS: the Board, on March 29, 2017, and the Stockholders, on April 11, 2017, have each approved an amendment to the Plan to increase the maximum aggregate number of Shares that may be sold under the Plan by 1,050,669 Shares (from 2,394,935 Shares to 3,445,604 Shares), as set forth below in this Amendment.

AMENDMENT

NOW, THEREFORE, the Plan is hereby amended as follows:

1. The first sentence of Section 3 of the Plan is hereby amended and restated in its entirety to read as follows:

“Subject to the provisions of Section 13 of the Plan, the maximum aggregate number of Shares that may be sold under the Plan is three million four hundred forty-five thousand six hundred four (3,445,604) Shares.”

2. Except as modified herein, the provisions of the Plan shall remain unchanged and in full force and effect.

***

EX-4.2

Exhibit 4.2

ALPINE IMMUNE SCIENCES, INC.

AMENDED AND RESTATED 2015 STOCK PLAN

STOCK OPTION AGREEMENT

1. Grant of Option. Alpine Immune Sciences, Inc., a Delaware corporation (the “Company”), hereby grants to             (the “Optionee”), an option (this “Option”) to purchase a total number of shares of Common Stock (the “Shares”) set forth in the Notice of Stock Option Grant, at the exercise price per share set forth in the Notice of Stock Option Grant (the “Exercise Price”) subject to the terms, definitions, and provisions of the Alpine Immune Sciences, Inc. Amended and Restated 2015 Stock Plan (the “Plan”) adopted by the Company, which is incorporated herein by reference. Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Option.

If designated an Incentive Stock Option in the Notice of Stock Option Grant, this Option is intended to qualify as an Incentive Stock Option as defined in Section 422 of the Code.

2. Exercise of Option. This Option shall be exercisable during its Term in accordance with the Vesting Schedule set out in the Notice of Stock Option Grant and with the provisions of Section 9 of the Plan as follows:

(a) Right to Exercise.

(i) This Option may not be exercised for a fraction of a share.

(ii) In the event of Optionee’s death, disability, or other termination of employment, the exercisability of the Option is governed by Sections 5, 6, and 7 below, subject to the limitation contained in Section 2(a)(i).

(iii) In no event may this Option be exercised after the date of expiration of the Term of this Option as set forth in the Notice of Stock Option Grant.

(b) Method of Exercise. This Option shall be exercisable by execution and delivery of the Exercise Notice and Restricted Stock Purchase Agreement attached hereto as Exhibit A (the “Exercise Agreement”) or of any other form of written notice approved for such purpose by the Company which shall state the election to exercise the Option, the number of Shares in respect of which the Option is being exercised, and such other representations and agreements as to the holder’s investment intent with respect to such shares of Common Stock as may be required by the Company pursuant to the provisions of the Plan. Such written notice shall be signed by Optionee and shall be delivered in person or by certified mail to the Secretary of the Company. The written notice shall be accompanied by payment of the Exercise Price. This Option shall be deemed to be exercised upon receipt by the Company of such written notice accompanied by the Exercise Price.

No Shares will be issued pursuant to the exercise of an Option unless such issuance and such exercise shall comply with all relevant provisions of applicable law and the requirements of any stock exchange upon which the Shares may then be listed. Assuming such compliance, for income tax purposes the Shares shall be considered transferred to Optionee on the date on which the Option is exercised with respect to such Shares.

3. Method of Payment. Payment of the Exercise Price shall be by any of the following, or a combination thereof, at the election of Optionee:

(a) cash or check;

(b) cancellation of indebtedness;

(c) surrender of other shares of Common Stock of the Company which (i) in the case of Shares acquired pursuant to the exercise of a Company option, have been owned by Optionee for more than six (6) months on the date of surrender, and (ii) have a fair market value on the date of surrender equal to the Exercise Price of the Shares as to which the Option is being exercised;

(d) if there is a public market for the Shares and they are registered under the Securities Act of 1933, as amended from time to time, delivery of a properly executed exercise notice together with irrevocable instructions to a broker to deliver promptly to the Company the amount of sale or loan proceeds required to pay the exercise price; or

(e) non-recourse indebtedness secured by the Shares, so long as such indebtedness is approved by the Administrator.

4. Restrictions on Exercise. This Option may not be exercised until such time as the Plan has been approved by the stockholders of the Company, or if the issuance of such Shares upon such exercise or the method of payment of consideration for such shares would constitute a violation of any applicable federal or state securities or other law or regulation, including any rule under Part 207 of Title 12 of the Code of Federal Regulations as promulgated by the Federal Reserve Board. As a condition to the exercise of this Option, the Company may require Optionee to make any representation and warranty to the Company as may be required by any applicable law or regulation.

5. Termination of Relationship. In the event of termination of Optionee’s Continuous Status as an Employee or Consultant, Optionee may, to the extent otherwise so entitled at the date of such termination (the “Termination Date”), exercise this Option during the Termination Period set forth in the Notice of Stock Option Grant. To the extent that Optionee was not entitled to exercise this Option at such Termination Date, or if Optionee does not exercise this Option within the Termination Period, the Option shall terminate. The Company will have the right, in its sole discretion, to repurchase any of the Optionee’s exercised Shares (to the extent so entitled) as set forth in the Plan.

6. Disability of Optionee. Notwithstanding the provisions of Section 5 above, in the event of termination of Continuous Status as an Employee or Consultant as a result of Optionee’s total and permanent disability (as defined in Section 22(e)(3) of the Code), Optionee may, but only within six (6) months from the Termination Date (but in no event later than the Expiration Date set forth in the Notice of Stock Option Grant), exercise this Option to the extent Optionee was entitled to exercise it as of such Termination Date. To the extent that Optionee was not entitled to exercise the Option as of the Termination Date, or if Optionee does not exercise such Option (to the extent so entitled) within the time specified in this Section 6(a), the Option shall terminate. The Company will have the right, in its sole discretion, to repurchase any of the Optionee’s exercised Shares (to the extent so entitled) as set forth in the Plan.

7. Death of Optionee. In the event of the death of Optionee (a) during the Term of this Option and while an Employee or Consultant of the Company and having been in Continuous Status as an Employee or Consultant since the date of grant of the Option, or (b) within thirty (30) days after Optionee’s Termination Date, the Option may be exercised at any time within twelve (12) months following the date of death (but in no event later than the Expiration Date set forth in the Notice of Stock Option Grant), by Optionee’s estate or by a person who acquired the right to exercise the Option by bequest or inheritance, but only to the extent of the right to exercise that had accrued at the Termination Date. The Company will have the right, in its sole discretion, to repurchase any of the Optionee’s exercised Shares (to the extent so entitled) as set forth in the Plan.

8. Non-Transferability of Option. This Option may not be transferred in any manner otherwise than by will or by the laws of descent or distribution and may be exercised during the lifetime of Optionee only by him or her. The terms of this Option shall be binding upon the executors, administrators, heirs, successors and assigns of Optionee.

9. Term of Option. This Option may be exercised only within the Term set forth in the Notice of Stock Option Grant, subject to the limitations set forth in Section 7 of the Plan.

10. Tax Consequences. Set forth below is a brief summary as of the date of this Option of certain of the federal tax consequences of exercise of this Option and disposition of the Shares under the laws in effect as of the Date of Grant. THIS SUMMARY IS NECESSARILY INCOMPLETE AND DOES NOT ADDRESS STATE TAX IMPLICATIONS OF OPTIONS GRANTED UNDER THE PLAN. IN ADDITION, THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE IN WAYS THAT COULD MAKE THE FOLLOWING DISCLOSURE OBSOLETE. OPTIONEE SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE SHARES.

(a) Exercise of Incentive Stock Option. If this Option qualifies as an Incentive Stock Option, there will be no regular federal income tax liability upon the exercise of the Option, although the excess, if any, of the fair market value of the Shares on the date of exercise over the Exercise Price will be treated as an adjustment to the alternative minimum tax for federal tax purposes and may subject Optionee to the alternative minimum tax in the year of exercise.

(b) Exercise of Nonstatutory Stock Option. If this Option does not qualify as an Incentive Stock Option, there may be a regular federal income tax liability upon the exercise of the Option. Optionee will be treated as having received compensation income (taxable at ordinary income tax rates) equal to the excess, if any, of the fair market value of the Shares on the date of exercise over the Exercise Price. If Optionee is an employee, the Company will be required to withhold from Optionee’s compensation or collect from Optionee and pay to the applicable taxing authorities an amount equal to a percentage of this compensation income at the time of exercise.

(c) Disposition of Shares. In the case of a Nonstatutory Stock Option, if Shares are held for at least one (1) year, any gain realized on disposition of the Shares will be treated as long-term capital gain for federal income tax purposes. In the case of an Incentive Stock Option, if Shares transferred pursuant to the Option are held for at least one (1) year after exercise and are disposed of at least two (2) years after the Date of Grant, any gain realized on disposition of the Shares will also be treated as long-term capital gain for federal income tax purposes. If Shares purchased under an Incentive Stock Option are disposed of within such one (1)-year period or within two (2) years after the Date of Grant, any gain realized on such disposition will be treated as compensation income (taxable at ordinary income rates) to the extent of the difference between the Exercise Price and the lesser of (i) the fair market value of the Shares on the date of exercise, or (ii) the sale price of the Shares.

(d) Notice of Disqualifying Disposition of Incentive Stock Option Shares. If the Option granted to Optionee herein is an Incentive Stock Option, and if Optionee sells or otherwise disposes of any of the Shares acquired pursuant to the Incentive Stock Option on or before the later of (i) the date two (2) years after the Date of Grant, or (ii) the date one (1) year after the date of exercise, Optionee shall immediately notify the Company in writing of such disposition. Optionee acknowledges and agrees that he or she may be subject to income tax withholding by the Company on the compensation income recognized by Optionee from the early disposition by payment in cash or out of the current earnings paid to Optionee.

11. Withholding Tax Obligations. Optionee understands that, upon exercising a Nonstatutory Stock Option, he or she will recognize income for tax purposes in an amount equal to the excess of the then fair market value of the Shares over the Exercise Price. However, the timing of this income recognition may be deferred for up to six (6) months if Optionee is subject to Section 16 of the Securities Exchange Act of 1934, as amended from time to time (the “Exchange Act”). If Optionee is an employee, the Company will be required to withhold from Optionee’s compensation, or collect from Optionee and pay to the applicable taxing authorities an amount equal to a percentage of this compensation income. Additionally, Optionee may at some point be required to satisfy tax withholding obligations with respect to the disqualifying disposition of an Incentive Stock Option. Optionee shall satisfy his or her tax withholding obligation arising upon the exercise of this Option by one or some combination of the following methods: (a) by cash payment, (b) out of Optionee’s current compensation, (c) if permitted by the Administrator, in its discretion, by surrendering to the Company Shares which (i) in the case of Shares previously acquired from the Company, have been owned by Optionee for more than six months on the date of surrender, and (ii) have a fair market value on the date of surrender equal to the minimum statutory withholding amount, or (d) by electing to have the Company withhold from the Shares to be issued upon exercise of the Option that number of Shares having a fair market value equal to the minimum statutory withholding amount. For this purpose, the fair market value of the Shares to be withheld shall be determined on the date that the amount of tax to be withheld is to be determined (the “Tax Date”).

If Optionee is subject to Section 16 of the Exchange Act (an “Insider”), any surrender of previously owned Shares to satisfy tax withholding obligations arising upon exercise of this Option must comply with the applicable provisions of Rule 16b-3 promulgated under the Exchange Act (“Rule 16b-3”).

All elections by Optionee to have Shares withheld to satisfy tax withholding obligations shall be made in writing in a form acceptable to the Administrator and shall be subject to the following restrictions:

(a) the election must be made on or prior to the applicable Tax Date;

(b) once made, the election shall be irrevocable as to the particular Shares of the Option as to which the election is made; and

(c) all elections shall be subject to the consent or disapproval of the Administrator.

12. Market Standoff Agreement. In connection with the initial public offering of the Company’s securities and upon request of the Company or the underwriters managing any underwritten offering of the Company’s securities, Optionee hereby agrees not to sell, make any short sale of, loan, grant any option for the purchase of, or otherwise dispose of any Shares (other than those included in the registration) without the prior written consent of the Company or such underwriters, as the case may be, for such period of time (not to exceed one hundred eighty (180) days) from the effective date of such registration as may be requested by the Company or such managing underwriters and to execute an agreement reflecting the foregoing as may be requested by the underwriters at the time of the public offering.

[Signature Page Follows]

This Agreement may be executed in two or more counterparts, each of which shall be deemed an original and all of which together shall constitute one document.

ALPINE IMMUNE SCIENCES, INC.,

a Delaware corporation

By:

Name:

Its:

OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO THE OPTION HEREOF IS EARNED ONLY BY CONTINUING EMPLOYMENT OR CONSULTANCY AT THE WILL OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS OPTION OR ACQUIRING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT NOTHING IN THIS AGREEMENT, NOR IN THE COMPANY’S STOCK PLAN WHICH IS INCORPORATED HEREIN BY REFERENCE, SHALL CONFER UPON OPTIONEE ANY RIGHT WITH RESPECT TO CONTINUATION OF EMPLOYMENT OR CONSULTANCY BY THE COMPANY, NOR SHALL IT INTERFERE IN ANY WAY WITH OPTIONEE’S RIGHT OR THE COMPANY’S RIGHT TO TERMINATE OPTIONEE’S EMPLOYMENT OR CONSULTANCY AT ANY TIME, WITH OR WITHOUT CAUSE.

Optionee acknowledges receipt of a copy of the Plan and represents that he or she is familiar with the terms and provisions thereof, and hereby accepts this Option subject to all of the terms and provisions thereof. Optionee has reviewed the Plan and this Option in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Option and fully understands all provisions of the Option. Optionee hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan or this Option.

Dated:
	Optionee

EXHIBIT A

ALPINE IMMUNE SCIENCES, INC.

AMENDED AND RESTATED 2015 STOCK PLAN

EXERCISE NOTICE AND RESTRICTED STOCK PURCHASE AGREEMENT

This Exercise Notice and Restricted Stock Purchase Agreement (“Agreement”) is made as of             , by and between Alpine Immune Sciences, Inc., a Delaware corporation (the “Company”), and             (“Purchaser”). To the extent any capitalized terms used in this Agreement are not defined, they shall have the meaning ascribed to them in the Amended and Restated 2015 Stock Plan.

1. Exercise of Option. Subject to the terms and conditions hereof, Purchaser hereby elects to exercise his or her option to purchase             shares of the Common Stock (the “Shares”) of the Company under and pursuant to the Company’s Amended and Restated 2015 Stock Plan (the “Plan”) and the Stock Option Agreement dated             , (the “Option Agreement”). The purchase price for the Shares shall be $            per Share for a total purchase price of $            . The term “Shares” refers to the purchased Shares and all securities received in replacement of the Shares or as stock dividends or splits, all securities received in replacement of the Shares in a recapitalization, merger, reorganization, exchange, or the like, and all new, substituted, or additional securities or other properties to which Purchaser is entitled by reason of Purchaser’s ownership of the Shares.

2. Time and Place of Exercise. The purchase and sale of the Shares under this Agreement shall occur at the principal office of the Company simultaneously with the execution and delivery of this Agreement in accordance with the provisions of Section 2(b) of the Option Agreement. On such date, the Company will deliver to Purchaser a certificate representing the Shares to be purchased by Purchaser (which shall be issued in Purchaser’s name) against payment of the exercise price therefor by Purchaser by (a) check made payable to the Company, (b) cancellation of indebtedness of the Company to Purchaser, (c) delivery of shares of the Common Stock of the Company in accordance with Section 3 of the Option Agreement, or (d) by a combination of the foregoing.

3. Limitations on Transfer. In addition to any other limitation on transfer created by applicable securities laws, Purchaser shall not assign, encumber, or dispose of any interest in the Shares except in compliance with the provisions below and applicable securities laws.

(a) Right of First Refusal. Before any Shares held by Purchaser or any transferee of Purchaser (either being sometimes referred to herein as the “Holder”) may be sold or otherwise transferred (including transfer by gift or operation of law), the Company or its assignee(s) shall have a right of first refusal to purchase the Shares on the terms and conditions set forth in this Section 3(a) (the “Right of First Refusal”).

(i) Notice of Proposed Transfer. The Holder of the Shares shall deliver to the Company a written notice (the “Notice”) stating: (i) the Holder’s bona fide intention to sell or otherwise transfer such Shares; (ii) the name of each proposed purchaser or other transferee (“Proposed Transferee”); (iii) the number of Shares to be transferred to each Proposed Transferee; and (iv) the terms and conditions of each proposed sale or transfer. The Holder shall offer the Shares at the same price (the “Offered Price”) and upon the same terms (or terms as similar as reasonably possible) to the Company or its assignee(s).

(ii) Exercise of Right of First Refusal. At any time within thirty (30) days after receipt of the Notice, the Company and/or its assignee(s) may, by giving written notice to the Holder, elect to purchase all, but not less than all, of the Shares proposed to be transferred to any one or more of the Proposed Transferees, at the purchase price determined in accordance with subsection (iii) below.

(iii) Purchase Price. The purchase price (“Purchase Price”) for the Shares purchased by the Company or its assignee(s) under this Section 3(a) shall be the Offered Price. If the Offered Price includes consideration other than cash, the cash equivalent value of the non-cash consideration shall be determined by the board of directors of the Company in good faith.

(iv) Payment. Payment of the Purchase Price shall be made, at the option of the Company or its assignee(s), in cash (by check), by cancellation of all or a portion of any outstanding indebtedness of the Holder to the Company (or, in the case of repurchase by an assignee, to the assignee), or by any combination thereof within thirty (30) days after receipt of the Notice or in the manner and at the times set forth in the Notice.

(v) Holder’s Right to Transfer. If all of the Shares proposed in the Notice to be transferred to a given Proposed Transferee are not purchased by the Company and/or its assignee(s) as provided in this Section 3(a), then the Holder may sell or otherwise transfer such Shares to that Proposed Transferee at the Offered Price or at a higher price; provided, however, that such sale or other transfer is consummated within sixty (60) days after the date of the Notice and provided further that any such sale or other transfer is effected in accordance with any applicable securities laws and the Proposed Transferee agrees in writing that the provisions of this Section 3 shall continue to apply to the Shares in the hands of such Proposed Transferee. If the Shares described in the Notice are not transferred to the Proposed Transferee within such period, or if the Holder proposes to change the price or other terms to make them more favorable to the Proposed Transferee, a new Notice shall be given to the Company, and the Company and/or its assignees shall again be offered the Right of First Refusal before any Shares held by the Holder may be sold or otherwise transferred.

(vi) Exception for Certain Family Transfers. Anything to the contrary contained in this Section 3(a) notwithstanding, the transfer of any or all of the Shares during Purchaser’s lifetime or on Purchaser’s death by will or intestacy to Purchaser’s Immediate Family or a trust for the benefit of Purchaser’s Immediate Family shall be exempt from the provisions of this Section 3(a). “Immediate Family” as used herein shall mean spouse, lineal descendant or antecedent, father, mother, brother, or sister. In such case, the transferee or other recipient shall receive and hold the Shares so transferred subject to the provisions of this Section, and there shall be no further transfer of such Shares except in accordance with the terms of this Section 3.

(b) Involuntary Transfer.

(i) Company’s Right to Purchase upon Involuntary Transfer. In the event, at any time after the date of this Agreement, of any transfer by operation of law or other involuntary transfer (including death or divorce, but excluding a transfer to Immediate Family as set forth in Section 3(a)(vi) above) of all or a portion of the Shares by the record holder thereof, the Company shall have an option to purchase all of the Shares transferred at the greater of the purchase price paid by Purchaser pursuant to this Agreement or the fair market value of the Shares on the date of transfer. Upon such a transfer, the person acquiring the Shares shall promptly notify the Secretary of the Company of such transfer. The right to purchase such Shares shall be provided to the Company for a period of thirty (30) days following receipt by the Company of written notice by the person acquiring the Shares.

(ii) Price for Involuntary Transfer. With respect to any stock to be transferred pursuant to Section 3(b)(i), the price per Share shall be a price set by the Board of Directors of the Company that will reflect the current value of the stock in terms of present earnings and future prospects of the Company. The Company shall notify Purchaser or his or her executor of the price so determined within thirty (30) days after receipt by it of written notice of the transfer or proposed transfer of Shares. However, if the Purchaser does not agree with the valuation as determined by the board of directors of the Company, the Purchaser shall be entitled to have the valuation determined by an independent appraiser to be mutually agreed upon by the Company and the Purchaser and whose fees shall be borne equally by the Company and the Purchaser.

(c) Assignment. The right of the Company to purchase any part of the Shares may be assigned in whole or in part to any stockholders or stockholders of the Company or other persons or organizations.

(d) Restrictions Binding on Transferees. All transferees of Shares or any interest therein will receive and hold such Shares or interest subject to the provisions of this Agreement. Any sale or transfer of the Company’s Shares shall be void unless the provisions of this Agreement are satisfied.

(e) Termination of Rights. The right of first refusal granted the Company by Section 3(a) above and the option to repurchase the Shares in the event of an involuntary transfer granted the Company by Section 3(b) above shall terminate upon the first sale of Common Stock of the Company to the general public pursuant to a registration statement filed with and declared effective by the Securities and Exchange Commission under the Securities Act. Upon termination of the right of first refusal described in Section 3(a) above, a new certificate or certificates representing the Shares not repurchased shall be issued, on request, without the legend referred to in Section 5(a)(ii) herein and delivered to Purchaser.

5. Investment and Taxation Representations. In connection with the purchase of the Shares, Purchaser represents to the Company the following:

(a) Purchaser is aware of the Company’s business affairs and financial condition and has acquired sufficient information about the Company to reach an informed and knowledgeable decision to acquire the securities. Purchaser is purchasing these securities for investment for his or her own account only and not with a view to, or for resale in connection with, any “distribution” thereof within the meaning of the Securities Act.

(b) Purchaser understands that the securities have not been registered under the Securities Act by reason of a specific exemption therefrom, which exemption depends upon, among other things, the bona fide nature of Purchaser’s investment intent as expressed herein.

(c) Purchaser understands that the Shares are “restricted securities” under applicable U.S. federal and state securities laws and that, pursuant to these laws, Purchaser must hold the Shares indefinitely unless they are registered with the Securities and Exchange Commission and qualified by state authorities, or an exemption from such registration and qualification requirements is available. Purchaser acknowledges that the Company has no obligation to register or qualify the Shares for resale. Purchaser further acknowledges that if an exemption from registration or qualification is available, it may be conditioned on various requirements including, but not limited to, the time and manner of sale, the holding period for the Shares, and requirements relating to the Company which are outside of the Purchaser’s control, and which the Company is under no obligation and may not be able to satisfy.

(d) Purchaser understands that Purchaser may suffer adverse tax consequences as a result of Purchaser’s purchase or disposition of the Shares. Purchaser represents that Purchaser has consulted any tax consultants Purchaser deems advisable in connection with the purchase or disposition of the Shares and that Purchaser is not relying on the Company for any tax advice.

6. Restrictive Legends and Stop-Transfer Orders.

(a) Legends. The certificate or certificates representing the Shares shall bear the following legends (as well as any legends required by applicable state and federal corporate and securities laws):

(i) THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), AND HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF. NO SUCH SALE OR DISPOSITION MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN OPINION OF COUNSEL IN A FORM SATISFACTORY TO FOR THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE ACT.

(ii) THE SHARES REPRESENTED BY THIS CERTIFICATE MAY BE TRANSFERRED ONLY IN ACCORDANCE WITH THE TERMS OF AN AGREEMENT BETWEEN THE COMPANY AND THE STOCKHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY.

(b) Stop-Transfer Notices. Purchaser agrees that, in order to ensure compliance with the restrictions referred to herein, the Company may issue appropriate “stop transfer” instructions to its transfer agent, if any, and that, if the Company transfers its own securities, it may make appropriate notations to the same effect in its own records.

(c) Refusal to Transfer. The Company shall not be required (i) to transfer on its books any Shares that have been sold or otherwise transferred in violation of any of the provisions of this Agreement, or (ii) to treat as owner of such Shares or to accord the right to vote or pay dividends to any purchaser or other transferee to whom such Shares shall have been so transferred.

7. No Employment Rights. Nothing in this Agreement shall affect in any manner whatsoever the right or power of the Company, or a parent or subsidiary of the Company, to terminate Purchaser’s employment, for any reason, with or without cause.

8. Market Stand-off Agreement. In connection with the initial public offering of the Company’s securities and upon request of the Company or the underwriters managing any underwritten offering of the Company’s securities, Purchaser agrees not to sell, make any short sale of, loan, grant any option for the purchase of, or otherwise dispose of any Shares (other than those included in the registration) without the prior written consent of the Company or such underwriters, as the case may be, for such period of time (not to exceed one hundred eighty (180) days) from the effective date of such registration as may be requested by the Company or such managing underwriters and to execute an agreement reflecting the foregoing as may be requested by the underwriters at the time of the public offering.

9. Miscellaneous.

(a) Governing Law. This Agreement and all acts and transactions pursuant hereto and the rights and obligations of the parties hereto shall be governed, construed and interpreted in accordance with the laws of the State of Delaware, without giving effect to principles of conflicts of law.

(b) Entire Agreement; Enforcement of Rights. This Agreement sets forth the entire agreement and understanding of the parties relating to the subject matter herein and merges all prior discussions between them. No modification of or amendment to this Agreement, nor any waiver of any rights under this Agreement, shall be effective unless in writing signed by the parties to this Agreement. The failure by either party to enforce any rights under this Agreement shall not be construed as a waiver of any rights of such party.

(c) Severability. If one (1) or more provisions of this Agreement are held to be unenforceable under applicable law, the parties agree to renegotiate such provision in good faith. In the event that the parties cannot reach a mutually agreeable and enforceable replacement for such provision, then (i) such provision shall be excluded from this Agreement, (ii) the balance of the Agreement shall be interpreted as if such provision were so excluded and (iii) the balance of the Agreement shall be enforceable in accordance with its terms.

(d) Construction. This Agreement is the result of negotiations between and has been reviewed by each of the parties hereto and their respective counsel, if any; accordingly, this Agreement shall be deemed to be the product of all of the parties hereto, and no ambiguity shall be construed in favor of or against any one of the parties hereto.

(e) Notices. Any notice required or permitted by this Agreement shall be in writing and shall be deemed sufficient when delivered personally or sent by telegram or fax or forty-eight (48) hours after being deposited in the U.S. mail, as certified or registered mail, with postage prepaid, and addressed to the party to be notified at such party’s address as set forth below or as subsequently modified by written notice.

(f) Counterparts. This Agreement may be executed in two (2) or more counterparts, each of which shall be deemed an original and all of which together shall constitute one (1) instrument.

(g) Successors and Assigns. The rights and benefits of this Agreement shall inure to the benefit of, and be enforceable by the Company’s successors and assigns. The rights and obligations of Purchaser under this Agreement may only be assigned with the prior written consent of the Company.

(h) Other Agreements. Purchaser covenants and agrees to sign and become a party to the Company’s then-current form of Voting Agreement, Stockholder’s Agreement, and any similar agreements to the extent applicable, as requested by the Company.

The parties have executed this Exercise Notice and Restricted Stock Purchase Agreement as of the date first set forth above.

COMPANY:

ALPINE IMMUNE SCIENCES, INC.,

a Delaware corporation

By:

Name:

Its:

Address:

PURCHASER:

NAME:

(Signature)

(Print Name)

Address:                                                                         

I,             , spouse of Purchaser, have read and hereby approve the foregoing Agreement. In consideration of the Company’s granting my spouse the right to purchase the Shares as set forth in the Agreement, I hereby agree to be irrevocably bound by the Agreement and further agree that any community property or other such interest shall hereby by similarly bound by the Agreement. I hereby appoint my spouse as my attorney-in-fact with respect to any amendment or exercise of any rights under the Agreement.

Spouse of Purchaser

EX-23.1

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Post-Effective Amendment No. 1 on Form S-8 to Form S-4 pertaining to the Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan of our report dated May 18, 2017, with respect to the financial statements of Alpine Immune Sciences, Inc. included in the Registration Statement on Form S-4 (File No. 333-218134) and related proxy statement/prospectus/information statement of Nivalis Therapeutics, Inc, filed with the Securities and Exchange Commission.

We also consent to the reference to our firm under the caption “Experts” and to the use of our report dated May 18, 2017, included in the Registration Statement on Form S-4 (File No. 333-218134) and related proxy statement/prospectus/information statement of Nivalis Therapeutics, Inc. for the registration of shares of its common stock.

/s/ Ernst & Young LLP

Seattle, Washington

September 7, 2017

EX-23.2

Exhibit 23.2

Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Post-Effective Amendment No. 1 on Form S-8 to Form S-4 pertaining to the Alpine Immune Sciences, Inc. (now known as AIS Operating Co., Inc.) Amended and Restated 2015 Stock Plan of our report dated February 13, 2017, with respect to the financial statements of Nivalis Therapeutics, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2016, filed with the Securities and Exchange Commission.

We also consent to the reference to our firm under the caption “Experts” and to the use of our report dated February 13, 2017, included in the Proxy Statement of Nivalis Therapeutics, Inc. that is made a part of the Registration Statement (Form S-4 No. 333-218134) and Prospectus of Nivalis Therapeutics, Inc. for the registration of shares of its common stock.

/s/ Ernst & Young LLP

Denver, Colorado

September 7, 2017