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X0202 SCHEDULE 13D/A 0000921895-22-001288 0000918923 XXXXXXXX LIVE 5 Class A ordinary share, par value $0.0001 per share 03/31/2026 false 0001821586 61559X104 MoonLake Immunotherapeutics DORFSTRASSE 29 ZUG V8 6300 JAMES KRATKY 415-525-8830 BVF PARTNERS L.P. 44 Montgomery St., 40th Floor San Francisco CA 94104 0000918923 N BIOTECHNOLOGY VALUE FUND L P a WC N DE 0.00 8302735.00 0.00 8302735.00 8302735.00 N 11.6 PN 0001803805 N BVF I GP LLC a AF N DE 0.00 8302735.00 0.00 8302735.00 8302735.00 N 11.6 OO 0001102444 N BIOTECHNOLOGY VALUE FUND II LP a WC N DE 0.00 6599722.00 0.00 6599722.00 6599722.00 N 9.2 PN 0001803806 N BVF II GP LLC a AF N DE 0.00 6599722.00 0.00 6599722.00 6599722.00 N 9.2 OO 0001660683 N Biotechnology Value Trading Fund OS LP a WC N E9 0.00 1039238.00 0.00 1039238.00 1039238.00 N 1.4 PN 0001660684 N BVF Partners OS Ltd. a AF N E9 0.00 1039238.00 0.00 1039238.00 1039238.00 N 1.4 CO 0001803809 N BVF GP HOLDINGS LLC a AF N DE 0.00 14902457.00 0.00 14902457.00 14902457.00 N 20.8 OO 0001055947 N BVF PARTNERS L P/IL a AF N DE 0.00 16001284.00 0.00 16001284.00 16001284.00 N 22.3 IA PN 0001056807 N BVF INC/IL a AF N DE 0.00 16001284.00 0.00 16001284.00 16001284.00 N 22.3 CO 0001233840 N LAMPERT MARK N a AF N X1 0.00 16001284.00 0.00 16001284.00 16001284.00 N 22.3 IN 0001920549 N Loy Spike a OO N X1 18985.00 0.00 18985.00 0.00 18985.00 N 0.03 IN Class A ordinary share, par value $0.0001 per share MoonLake Immunotherapeutics DORFSTRASSE 29 ZUG V8 6300 Item 3 is hereby amended and restated to read as follows: The Shares beneficially owned by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Account were purchased with working capital. The aggregate cost basis of the 8,302,735 Shares directly beneficially owned by BVF is approximately $27,709,362, including brokerage commissions. The aggregate cost basis of the 6,599,722 Shares directly beneficially owned by BVF2 is approximately $21,077,776, including brokerage commissions. The aggregate cost basis of the 1,039,238 Shares directly beneficially owned by Trading Fund OS is approximately $3,277,670, including brokerage commissions. The aggregate cost basis of the 59,589 Shares held in the Partners Managed Account is approximately $595,890, including brokerage commissions. The Shares beneficially owned by Mr. Loy were awarded to him by the Issuer in connection with his service as a director. Item 5(a) is hereby amended and restated to read as follows: The aggregate percentage of Shares reported owned by each person named herein is based on 71,727,875 Shares outstanding as of February1, 2026, which is the total number of Shares outstanding as reported in the Issuer's Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 25, 2026. As of the date hereof, (i) BVF beneficially owned 8,302,735 Shares, representing percentage ownership of approximately 11.6% of the Shares outstanding, (ii) BVF2 beneficially owned 6,599,722 Shares, representing percentage ownership of approximately 9.2% of the Shares outstanding, (iii) Trading Fund OS beneficially owned 1,039,238 Shares, representing percentage ownership of approximately 1.4% of the Shares outstanding, and (iv) 59,589 Shares were held in the Partners Managed Account, representing percentage ownership of less than 1% of the Shares outstanding. BVF GP, as the general partner of BVF, may be deemed to beneficially own the 8,302,735 Shares beneficially owned by BVF, representing percentage ownership of approximately 11.6% of the Shares outstanding. BVF2 GP, as the general partner of BVF2, may be deemed to beneficially own the 6,599,722 Shares beneficially owned by BVF2, representing percentage ownership of approximately 9.2% of the Shares outstanding. Partners OS, as the general partner of Trading Fund OS, may be deemed to beneficially own the 1,039,238 Shares beneficially owned by Trading Fund OS, representing percentage ownership of approximately 1.4% of the Shares outstanding. BVF GPH, as the sole member of each of BVF GP and BVF2 GP, may be deemed to beneficially own the 14,902,457 Shares beneficially owned in the aggregate by BVF and BVF2, representing percentage ownership of approximately 20.8% of the Shares outstanding. Partners, as the investment manager of BVF, BVF2, Trading Fund OS and the Partners Managed Account and the sole member of Partners OS, may be deemed to beneficially own the 16,001,284 Shares beneficially owned in the aggregate by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Account, representing percentage ownership of approximately 22.3% of the Shares outstanding. BVF Inc., as the general partner of Partners, may be deemed to beneficially own the 16,001,284 Shares beneficially owned by Partners, representing percentage ownership of approximately 22.3% of the Shares outstanding. Mr. Lampert, as a director and officer of BVF Inc., may be deemed to beneficially own the 16,001,284 Shares beneficially owned by BVF Inc., representing percentage ownership of approximately 22.3% of the Shares outstanding. As of the date hereof, Mr. Loy beneficially owned 18,985 Shares, which consist of Shares issuable upon the exercise of certain options that are exercisable within sixty days hereof, representing percentage ownership of less than 1%. The foregoing should not be construed in and of itself as an admission by any Reporting Person as to beneficial ownership of any Shares owned by another Reporting Person. BVF GP disclaims beneficial ownership of the Shares beneficially owned by BVF. BVF2 GP disclaims beneficial ownership of the Shares beneficially owned by BVF2. Partners OS disclaims beneficial ownership of the Shares beneficially owned by Trading Fund OS. BVF GPH disclaims beneficial ownership of the Shares beneficially owned by BVF and BVF2. Each of Partners, BVF Inc. and Mr. Lampert disclaims beneficial ownership of the Shares beneficially owned by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Account. Mr. Loy disclaims beneficial ownership of the Shares reported herein that he does not directly own. Item 5(b) is hereby amended and restated to read as follows: Each of BVF, BVF2 and Trading Fund OS shares with Partners voting and dispositive power over the Shares each such entity beneficially owns. BVF shares with BVF GP voting and dispositive power over the Shares beneficially owned by BVF. BVF2 shares with BVF2 GP voting and dispositive power over the Shares beneficially owned by BVF2. Each of BVF GP and BVF2 GP shares with BVF GPH voting and dispositive power over the Shares each such entity beneficially owns. Trading Fund OS shares with Partners OS voting and dispositive power over the Shares beneficially owned by Trading Fund OS. Partners, BVF Inc. and Mr. Lampert share voting and dispositive power over the Shares they may be deemed to beneficially own with BVF, BVF GP, BVF2, BVF2 GP, Trading Fund OS, Partners OS and BVF GPH and held in the Partners Managed Account. Item 5(c) is hereby amended and restated to read as follows: On March 31, 2026, (i) BVF sold 1,932,354 Shares at a price of $16.79 per Share, (ii) BVF2 sold 1,569,116 Shares at a price of $16.79 per Share, and (iii) Trading Fund OS sold 248,530 Shares at a price of $16.79 per Share. Except as set forth herein, none of the Reporting Persons has entered into any transactions in the securities of the Issuer during the past 60 days. BIOTECHNOLOGY VALUE FUND L P /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BVF I GP LLC /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BIOTECHNOLOGY VALUE FUND II LP /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BVF II GP LLC /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 Biotechnology Value Trading Fund OS LP /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BVF Partners OS Ltd. /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BVF GP HOLDINGS LLC /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BVF PARTNERS L P/IL /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 BVF INC/IL /s/ Mark N. Lampert Mark N. Lampert, Authorized Signatory 04/02/2026 LAMPERT MARK N /s/ Mark N. Lampert Mark N. Lampert 04/02/2026 Loy Spike /s/ Spike Loy Spike Loy 04/02/2026