# EDGAR Filing Document

**Accession Number:** 0001821586
**File Stem:** 0000921895-25-002943
**Filing Date:** 2025-11
**Character Count:** 31685
**Document Hash:** 62dbf84b8de34ecfb1a29a69343c0735
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000921895-25-002943.hdr.sgml**: 20251110

**ACCESSION NUMBER**: 0000921895-25-002943

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20251110

**DATE AS OF CHANGE**: 20251110

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MoonLake Immunotherapeutics
- **CENTRAL INDEX KEY:** 0001821586
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-91803
- **FILM NUMBER:** 251467505

**BUSINESS ADDRESS:**
- **STREET 1:** DORFSTRASSE 29
- **CITY:** ZUG
- **STATE:** V8
- **ZIP:** 6300
- **BUSINESS PHONE:** 41 41 510 8022

**MAIL ADDRESS:**
- **STREET 1:** DORFSTRASSE 29
- **CITY:** ZUG
- **STATE:** V8
- **ZIP:** 6300

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Helix Acquisition Corp
- **DATE OF NAME CHANGE:** 20200818
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** BIOTECHNOLOGY VALUE FUND L P
- **CENTRAL INDEX KEY:** 0000918923
- **STANDARD INDUSTRIAL CLASSIFICATION:** INVESTMENT ADVICE [6282]
- **ORGANIZATION NAME:** 02 Finance
- **EIN:** 363924731
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A

**BUSINESS ADDRESS:**
- **STREET 1:** 44 MONTGOMERY STREET
- **STREET 2:** 40TH FL
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94104
- **BUSINESS PHONE:** 3125066500

**MAIL ADDRESS:**
- **STREET 1:** 44 MONTGOMERY STREET
- **STREET 2:** 40TH FL
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94104

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 4)**

**MoonLake Immunotherapeutics**

*(Name of Issuer)*

**Class A ordinary share, par value $0.0001 per share**

*(Title of Class of Securities)*

**61559X104**

*(CUSIP Number)*

**JAMES KRATKY**<br>BVF PARTNERS L.P.<br>44 Montgomery St., 40th Floor<br>San Francisco CA 94104<br>415-525-8830

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

**11/06/2025**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BIOTECHNOLOGY VALUE FUND L P** | Name of reporting person<br>**BIOTECHNOLOGY VALUE FUND L P** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**WC** | Source of funds (See Instructions)<br>**WC** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**10235089.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**10235089.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**10235089.00** | Aggregate amount beneficially owned by each reporting person<br>**10235089.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**14.3%** | Percent of class represented by amount in Row (11)<br>**14.3%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**PN** | Type of Reporting Person (See Instructions)<br>**PN** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BVF I GP LLC** | Name of reporting person<br>**BVF I GP LLC** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**10235089.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**10235089.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**10235089.00** | Aggregate amount beneficially owned by each reporting person<br>**10235089.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**14.3%** | Percent of class represented by amount in Row (11)<br>**14.3%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BIOTECHNOLOGY VALUE FUND II LP** | Name of reporting person<br>**BIOTECHNOLOGY VALUE FUND II LP** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**WC** | Source of funds (See Instructions)<br>**WC** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**8168838.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**8168838.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**8168838.00** | Aggregate amount beneficially owned by each reporting person<br>**8168838.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**11.4%** | Percent of class represented by amount in Row (11)<br>**11.4%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**PN** | Type of Reporting Person (See Instructions)<br>**PN** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BVF II GP LLC** | Name of reporting person<br>**BVF II GP LLC** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**8168838.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**8168838.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**8168838.00** | Aggregate amount beneficially owned by each reporting person<br>**8168838.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**11.4%** | Percent of class represented by amount in Row (11)<br>**11.4%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Biotechnology Value Trading Fund OS LP** | Name of reporting person<br>**Biotechnology Value Trading Fund OS LP** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**WC** | Source of funds (See Instructions)<br>**WC** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**CAYMAN ISLANDS** | Citizenship or place of organization<br>**CAYMAN ISLANDS** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**1287768.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**1287768.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**1287768.00** | Aggregate amount beneficially owned by each reporting person<br>**1287768.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**1.8%** | Percent of class represented by amount in Row (11)<br>**1.8%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**PN** | Type of Reporting Person (See Instructions)<br>**PN** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BVF Partners OS Ltd.** | Name of reporting person<br>**BVF Partners OS Ltd.** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**CAYMAN ISLANDS** | Citizenship or place of organization<br>**CAYMAN ISLANDS** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**1287768.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**1287768.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**1287768.00** | Aggregate amount beneficially owned by each reporting person<br>**1287768.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**1.8%** | Percent of class represented by amount in Row (11)<br>**1.8%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BVF GP HOLDINGS LLC** | Name of reporting person<br>**BVF GP HOLDINGS LLC** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**18403927.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**18403927.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**18403927.00** | Aggregate amount beneficially owned by each reporting person<br>**18403927.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**25.8%** | Percent of class represented by amount in Row (11)<br>**25.8%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BVF PARTNERS L P/IL** | Name of reporting person<br>**BVF PARTNERS L P/IL** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**19751284.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**19751284.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**19751284.00** | Aggregate amount beneficially owned by each reporting person<br>**19751284.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**27.7%** | Percent of class represented by amount in Row (11)<br>**27.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IA** | Type of Reporting Person (See Instructions)<br>**IA** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**BVF INC/IL** | Name of reporting person<br>**BVF INC/IL** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**19751284.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**19751284.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**19751284.00** | Aggregate amount beneficially owned by each reporting person<br>**19751284.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**27.7%** | Percent of class represented by amount in Row (11)<br>**27.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**LAMPERT MARK N** | Name of reporting person<br>**LAMPERT MARK N** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**X1** | Citizenship or place of organization<br>**X1** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**19751284.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**19751284.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**19751284.00** | Aggregate amount beneficially owned by each reporting person<br>**19751284.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**27.7%** | Percent of class represented by amount in Row (11)<br>**27.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

| **CUSIP No.** | **61559X104** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Loy Spike** | Name of reporting person<br>**Loy Spike** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**X1** | Citizenship or place of organization<br>**X1** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**18985.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**18985.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**18985.00** | Aggregate amount beneficially owned by each reporting person<br>**18985.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**0.03%** | Percent of class represented by amount in Row (11)<br>**0.03%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Class A ordinary share, par value $0.0001 per share

**(b) Name of Issuer:**
MoonLake Immunotherapeutics

**(c) Address of Issuer's Principal Executive Offices:**
DORFSTRASSE 29, ZUG, V8, 6300

This Amendment No. 4 to the Schedule 13D is being filed due to a change in the percentage of the outstanding number of Shares owned by the Reporting Persons solely due to an increase in the number of Shares outstanding.

**Item 5. Interest in Securities of the Issuer**

**(a)**
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 71,373,579 Shares outstanding as of November 6, 2025, which is the total number of Shares outstanding following the closing of the Issuer's offering as reported in the Issuer's Prospectus Supplement filed with the Securities and Exchange Commission on November 5, 2025.

**(b)**
Item 5(b) is hereby amended and restated to read as follows:

As of the date hereof, (i) BVF beneficially owned 10,235,089 Shares, representing percentage ownership of approximately 14.3% of the Shares outstanding, (ii) BVF2 beneficially owned 8,168,838 Shares, representing percentage ownership of approximately 11.4% of the Shares outstanding, (iii) Trading Fund OS beneficially owned 1,287,768 Shares, representing percentage ownership of approximately 1.8% 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 10,235,089 Shares beneficially owned by BVF, representing percentage ownership of approximately 14.3% of the Shares outstanding.

BVF2 GP, as the general partner of BVF2, may be deemed to beneficially own the 8,168,838 Shares beneficially owned by BVF2, representing percentage ownership of approximately 11.4% of the Shares outstanding.

Partners OS, as the general partner of Trading Fund OS, may be deemed to beneficially own the 1,287,768 Shares beneficially owned by Trading Fund OS, representing percentage ownership of approximately 1.8% 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 18,403,927 Shares beneficially owned in the aggregate by BVF and BVF2, representing percentage ownership of approximately 25.8% 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 19,751,284 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 27.7% of the Shares outstanding.

BVF Inc., as the general partner of Partners, may be deemed to beneficially own the 19,751,284 Shares beneficially owned by Partners, representing percentage ownership of approximately 27.7% of the Shares outstanding.

Mr. Lampert, as a director and officer of BVF Inc., may be deemed to beneficially own the 19,751,284 Shares beneficially owned by BVF Inc., representing percentage ownership of approximately 27.7% 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%.

**(c)**
Item 5(c) is hereby amended and restated to read as follows:

The Reporting Persons have not entered into any transactions in the securities of the Issuer during the past sixty days.

**Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.**

Item 6 is hereby amended to add the following:

On June 5, 2025, Mr. Loy was granted stock options in connection with his service as a director of the Issuer that represent a right to purchase 6,682 Shares. Such options (a) will vest in full on the earlier of (i) June 5, 2026 and (ii) the date of the Issuer's next annual general meeting of shareholders, subject to Mr. Loy's continued service to the Issuer, (b) have an exercise price of $48.83 per Share and (c) expire on June 5, 2035.

### SIGNATURE

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

**Reporting Person:** BIOTECHNOLOGY VALUE FUND L P

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BVF I GP LLC

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BIOTECHNOLOGY VALUE FUND II LP

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BVF II GP LLC

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** Biotechnology Value Trading Fund OS LP

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BVF Partners OS Ltd.

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BVF GP HOLDINGS LLC

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BVF PARTNERS L P/IL

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** BVF INC/IL

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert, Authorized Signatory

**Date:** 11/10/2025

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

**Reporting Person:** LAMPERT MARK N

**Signature:** /s/ Mark N. Lampert

**Name/Title:** Mark N. Lampert

**Date:** 11/10/2025

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

**Reporting Person:** Loy Spike

**Signature:** /s/ Spike Loy

**Name/Title:** Spike Loy

**Date:** 11/10/2025