SCHEDULE: Biotechnology Value Fund Group Updates Mirum Pharma Stake

Biotechnology Value Fund and its affiliates reported a collective 3.0% passive ownership stake in Mirum Pharmaceuticals, Inc. as of September 30, 2025.

Summary

• Biotechnology Value Fund L.P. (BVF) and its affiliated entities, including BVF I GP LLC, Biotechnology Value Fund II L.P. (BVF2), BVF II GP LLC, Biotechnology Value Trading Fund OS LP (Trading Fund OS), BVF Partners OS Ltd., BVF GP Holdings LLC (BVF GPH), BVF Partners L.P. (Partners), BVF Inc., and Mark N. Lampert, collectively reported beneficial ownership of Mirum Pharmaceuticals, Inc. common stock.
• As of September 30, 2025, the aggregate beneficial ownership by Partners, BVF Inc., and Mr. Lampert is 1,495,290 shares, representing approximately 3.0% of the outstanding shares.
• This 3.0% stake includes shares held by BVF (1.5%), BVF2 (1.2%), Trading Fund OS (0.2%), and 29,791 shares held in a Partners Managed Account.
• The percentages are based on 50,237,647 shares outstanding as of August 1, 2025, as disclosed in Mirum Pharmaceuticals' Form 10-Q filed on August 6, 2025.
• The reporting persons certified that the securities were not acquired and are not held for the purpose of changing or influencing control of the issuer, other than activities solely in connection with a nomination under §§ 240.14a-11.

Sentiment

Score: 6

Explanation: The filing is a routine disclosure of passive beneficial ownership by an institutional investor group. While not directly impacting company operations, the continued stake by a specialized biotech fund can be viewed as a moderately positive signal of investor confidence.

Positives

• A specialized biotechnology investment fund group maintains a significant, albeit passive, ownership stake in Mirum Pharmaceuticals, which could be interpreted as a vote of confidence in the company's long-term prospects.

Negatives

• No specific negative information regarding Mirum Pharmaceuticals, Inc. is contained within this beneficial ownership disclosure.

Risks

• The filing itself does not detail specific risks related to Mirum Pharmaceuticals, Inc.'s operations or financial health. It is a disclosure of beneficial ownership.

Future Outlook

This Schedule 13G filing does not contain any forward-looking statements or guidance from Mirum Pharmaceuticals, Inc. or the reporting persons regarding the issuer's future performance.

Industry Context

The filing indicates continued interest from a specialized biotechnology investment fund in Mirum Pharmaceuticals, a company operating within the biotechnology sector. Such institutional ownership is common in the industry, particularly for companies with promising pipelines or market positions.

Stakeholder Impact

• Shareholders: The disclosure provides transparency regarding a significant institutional investor's stake, which can influence market perception and trading activity.
• Company Management: Awareness of a significant, albeit passive, institutional shareholder may influence strategic decisions, though the filing explicitly states no intent to control.

Key Dates

Keywords

Mirum Pharmaceuticals, Biotechnology Value Fund, BVF, MRUM, Beneficial Ownership, Institutional Investor, SEC Filing, Schedule 13G, Biotech, Pharmaceuticals