SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

[Rule 13d-101]

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO § 21.16d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO § 240.13D-2(a)

(Amendment No. 5)*

Alpine Immune Sciences, Inc.

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

02083G100

(CUSIP Number)

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

August 15, 2018

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box ☐.

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See § 240.13d-7 for other parties to whom copies are to be sent.

(Continued on following pages)
(Page 1 of 16 Pages)

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

SCHEDULE 13D

SCHEDULE 13D

SCHEDULE 13D

SCHEDULE 13D

SCHEDULE 13D

(1) Comprised of 197,523 shares held by Deerfield Special Situations Fund, L.P., 76,015 shares held by Deerfield Private Design Fund, L.P., 122,350 shares held by Deerfield Private Design International, L.P., 137,306 shares held by Deerfield Private Design Fund II, L.P., and 157,343 shares held by Deerfield Private Design International II, L.P.

SCHEDULE 13D

(2) Comprised of 197,523 shares held by Deerfield Special Situations Fund, L.P., 76,015 shares held by Deerfield Private Design Fund, L.P., 122,350 shares held by Deerfield Private Design International, L.P., 137,306 shares held by Deerfield Private Design Fund II, L.P., and 157,343 shares held by Deerfield Private Design International II, L.P.

SCHEDULE 13D

(3) Comprised of 197,523 shares held by Deerfield Special Situations Fund, L.P., 76,015 shares held by Deerfield Private Design, L.P., 122,350 shares held by Deerfield Private Design International, L.P., 137,306 shares held by Deerfield Private Design Fund II, L.P., and 157,343 shares held by Deerfield Private Design International II, L.P.

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This Amendment No. 5 (this “Amendment”) to Schedule 13D amends the Schedule 13D filed on July 28, 2017 by (i) Deerfield Mgmt, L.P. (“Deerfield Mgmt”), (ii) Deerfield Special Situations Fund, L.P. (“Deerfield Special Situations Fund”), (iii) Deerfield Management Company, L.P. (“Deerfield Management”), (iv) Deerfield Private Design Fund, L.P. (“Deerfield Private Design”), (v) Deerfield Private Design International, L.P. (“Deerfield Private Design International”), (vi) Deerfield Private Design Fund II, L.P. (“Deerfield Private Design II”), (vii) Deerfield Private Design International II, L.P. (“Deerfield Private Design International II”) and (viii) James E. Flynn, a natural person (“Flynn” and collectively with Deerfield Mgmt, Deerfield Special Situations Fund, Deerfield Management, Deerfield Private Design, Deerfield Private Design International, Deerfield Private Design II and Deerfield Private Design International II, the “Reporting Persons”), with respect to the securities of Alpine Immune Sciences, Inc. (formerly, Nivalis Therapeutics, Inc.) (the “Issuer”), as amended by Amendment Nos. 1, 2, 3 and 4 thereto, filed on September 20, 2016, April 25, 2017, July 28, 2017 and August 22, 2017, respectively (as amended, the “Schedule 13D”). Deerfield Special Situations Fund, Deerfield Private Design, Deerfield Private Design International, Deerfield Private Design II and Deerfield Private Design International II are collectively referred to herein as the “Funds.”

Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the Scheduled 13D.

Item 5. Interest in Securities of the Issuer.

Items 5(a), (b), (c) and (e) of the Schedule 13D are hereby amended and restated as follows:

(a)        

(1)       Deerfield Mgmt

Number of shares: 690,537 (comprised of shares held by Deerfield Special Situations Fund, Deerfield Private Design, Deerfield Private Design International, Deerfield Private Design II and Deerfield Private Design International II)

Percentage of shares: 4.99%

(2)       Deerfield Management

Number of shares: 690,537 (comprised of shares held by Deerfield Special Situations Fund, Deerfield Private Design, Deerfield Private Design International, Deerfield Private Design II and Deerfield Private Design International II)

Percentage of shares: 4.99%

(3)       Deerfield Special Situations Fund

Number of shares: 197,523

Percentage of shares: 1.43%

(4)      Deerfield Private Design

Number of shares: 76,015

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Percentage of shares: 0.55%

(5)       Deerfield Private Design International

Number of Shares: 122,350

Percentage of Shares: 0.88%

(6)       Deerfield Private Design II

Number of Shares: 137,306

Percentage of Shares: 0.99%

(7)       Deerfield Private Design International II

Number of Shares: 157,343

Percentage of Shares: 1.14%

(8)        Flynn

Number of shares: 690,537 (comprised of shares held by Deerfield Special Situations Fund, Deerfield Private Design, Deerfield Private Design International, Deerfield Private Design II and Deerfield Private Design International II)

Percentage of shares: 4.99%

(b)       

(1)       Deerfield Mgmt

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 690,537

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 690,537

(2)       Deerfield Management

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 690,537

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 690,537

(3)       Deerfield Special Situations Fund

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 197,523

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 197,523

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(4)       Deerfield Private Design

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 76,015

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 76,015

(5)       Deerfield Private Design International

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 122,350

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 122,350

(6)       Deerfield Private Design II

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 137,306

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 137,306

(7)       Deerfield Private Design International II

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 157,343

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 157,343

(8)       Flynn

Sole power to vote or direct the vote: 0

Shared power to vote or direct the vote: 690,537

Sole power to dispose or to direct the disposition: 0

Shared power to dispose or direct the disposition: 690,537

Flynn is the sole member of the general partner of each of Deerfield Mgmt and Deerfield Management. Deerfield Mgmt is the general partner, and Deerfield Management is the investment advisor, of Deerfield Special Situations Fund, Deerfield Private Design, Deerfield Private Design International, Deerfield Private Design II and Deerfield Private Design International II.

(c) Transactions in the Common Stock effected by the Reporting Persons in the last sixty (60) days are set forth on Schedule A to this Amendment. All of the transactions reflected in Schedule A to this Amendment were effected in open market transactions on the Nasdaq Global Market in the ordinary course of the applicable Reporting Person’s business.

(e)  As of August 17, 2018, the Reporting Persons ceased to beneficially own more than five percent of the Common Stock.

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SIGNATURE

After reasonable inquiry and to the best of their knowledge and belief, the undersigned certify that the information set forth in this statement is true, complete and correct.

Dated: August 20, 2018

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Schedule A

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* Each price per share reported in the “Price per Share” column of this Schedule A is a weighted average price, except with respect to trades on August 8, 2018. The Reporting Persons undertake to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in the “Price Range” column of this Schedule A.

** The shares were sold in multiple transactions at prices within the price range indicated (unless otherwise indicated).