Biotech Fund Reveals $15 Million MoonLake Exit After Stock’s 90% Crash

On November 14, MPM BioImpact reported in a U.S. Securities and Exchange Commission filing that it sold out its MoonLake Immunotherapeutics position, reducing exposure by $14.8 million in the third quarter.

What happened

According to a U.S. Securities and Exchange Commission filing dated November 14, MPM BioImpact fully sold its stake in MoonLake Immunotherapeutics (NASDAQ:MLTX) during the third quarter. The fund disposed of 313,571 shares, eliminating a position that previously made up 2.6% of its assets under management. The move represented an estimated $14.8 million reduction based on quarterly average prices.

What Else to Know

Top holdings after the filing:

• NASDAQ:MDGL: $46.1 million (7.5% of AUM)
• NASDAQ:CGEM: $45.4 million (7.4% of AUM)
• NASDAQ:RNA: $33.1 million (5.4% of AUM)
• NASDAQ:TRVI: $31.2 million (5.1% of AUM)
• NASDAQ:EWTX: $27.9 million (4.6% of AUM)

As of Wednesday's market close, shares were priced at $13.80, down a staggering 74% from a year earlier and vastly underperforming the S&P 500, which is up 13% in the same period.

Company Overview

Company Snapshot

MoonLake Immunotherapeutics is a Switzerland-based clinical-stage biotechnology company that is developing Sonelokimab, an investigational Nanobody therapy targeting inflammatory diseases such as hidradenitis suppurativa, psoriatic arthritis, and axial spondyloarthritis. The company operates a clinical-stage biopharmaceutical model, investing in research and development to advance its pipeline through clinical trials, with future revenue potential dependent on successful product commercialization and regulatory approval. Primary customers will include healthcare providers, hospitals, and specialty clinics treating patients with chronic inflammatory conditions, with a focus on unmet medical needs in immunology.

Foolish Take

This transaction comes at a wildly volatile time for MoonLake, whose stock collapsed nearly 90% in a single day in late September after mixed Phase 3 results surfaced for its investigational nanobody, sonelokimab—an event that triggered a class-action lawsuit and wiped out billions in market value. Whether this fund exited before or after that shock remains unclear from the filing, but a full divestiture during such an inflection point underscores how quickly conviction can shift when sentiment and data conflict.

According to the latest SEC disclosure, the manager sold all 313,571 shares of MoonLake Immunotherapeutics in the third quarter—an estimated $14.8 million reversal that previously accounted for 2.6% of reportable assets. It also exited MBX Biosciences and Crinetics Pharmaceuticals during the same period, tightening exposure to high-volatility clinical names.

MoonLake, meanwhile, continues to advance sonelokimab. In its Q3 release, which came earlier this month, the company reported $380.5 million in cash—projecting runway into the second half of 2027—and highlighted new Phase 2 data and a scheduled December 15 meeting with the FDA to assess the adequacy of its evidence package for sonelokimab.

For long-term investors, the story serves as a warning of the risk in these types of investments, but for those holding on, the outlook now hinges less on the September shock and more on whether MoonLake can translate promising data into regulatory momentum.

Glossary

13F reportable assets: Assets a fund must disclose quarterly to the SEC, showing holdings in U.S. publicly traded securities.
Assets under management (AUM): The total market value of investments managed by a fund or investment firm.
Full exit: When an investor sells all shares of a particular holding, ending their position in that asset.
Exposure: The amount of capital or percentage of a portfolio invested in a particular asset or sector.
Stake: The ownership interest or number of shares held in a company by an investor or fund.
Clinical-stage: Refers to a biotechnology or pharmaceutical company developing drugs that are currently being tested in human clinical trials.
Nanobody: A small antibody fragment derived from camelids, used in developing targeted therapies for diseases.
Pipeline: The portfolio of drug candidates a biopharmaceutical company is developing, typically at various stages of research and trials.
Commercialization: The process of bringing a new product or therapy to market and generating sales.
Regulatory approval: Official authorization from government agencies allowing a drug or therapy to be marketed and sold.
Unmet medical needs: Health conditions for which current treatments are inadequate or unavailable.
TTM: The 12-month period ending with the most recent quarterly report.

Jonathan Ponciano has no position in any of the stocks mentioned. The Motley Fool recommends Cullinan Therapeutics. The Motley Fool has a disclosure policy.