SCHEDULE 13G/A: Baker Bros. Advisors Maintain Significant 8.9% Stake in Rhythm Pharmaceuticals

Baker Bros. Advisors and its affiliates have filed an Amendment No. 7 to Schedule 13G, reporting a continued beneficial ownership of 8.9% of Rhythm Pharmaceuticals, Inc.'s common stock as of March 31, 2025.

Summary

• Baker Bros. Advisors LP, Baker Bros. Advisors (GP) LLC, Julian C. Baker, and Felix J. Baker (collectively, the "Reporting Persons") filed an Amendment No. 7 to their Schedule 13G for Rhythm Pharmaceuticals, Inc.
• As of March 31, 2025, the Reporting Persons beneficially own an aggregate of 5,604,483 shares of Rhythm Pharmaceuticals, Inc. Common Stock.
• This represents 8.9% of the outstanding Common Stock, based on 63,223,727 shares outstanding as of February 24, 2025, as reported in the Issuer's Form 10-K filed on February 28, 2025.
• The ownership is primarily held by Baker Brothers Life Sciences, L.P. (5,134,192 shares or 8.1%) and 667, L.P. (470,291 shares or 0.8%).
• The Reporting Persons also hold Series A Convertible Preferred stock, which is convertible into Common Stock on a 1-for-20.8333 basis, but conversion is currently restricted by a 4.99% beneficial ownership limitation.
• The purpose of the acquisition and holding of these securities is stated as being in the ordinary course of business, not for changing or influencing control of the issuer, except for activities related to nominations under Rule 14a-11.

Sentiment

Score: 7

Explanation: The filing indicates a stable, significant long-term investment by a prominent life sciences investor, which is generally positive. The limitations on preferred stock conversion are a minor negative but expected for such instruments.

Positives

• Continued significant investment by Baker Bros. Advisors, a prominent life sciences investor, indicating ongoing confidence in Rhythm Pharmaceuticals.
• The holding of Series A Convertible Preferred stock provides potential for future equity conversion, although currently restricted by beneficial ownership limitations.

Negatives

• The beneficial ownership limitation of 4.99% on the Series A Convertible Preferred stock prevents immediate conversion, potentially limiting the investor's flexibility.

Risks

• The number of shares of Common Stock that may be issued upon conversion of the Series A Convertible Preferred by the holders may change depending upon changes in the outstanding Common Stock.
• The current beneficial ownership limitation (Maximum Percentage) of 4.99% prevents the Funds from converting any Series A Convertible Preferred stock at this time.

Future Outlook

The document indicates that the Funds may, by written notice to the Issuer, increase or decrease the Maximum Percentage applicable to the Series A Convertible Preferred conversion to any other percentage not exceeding 19.99%, with such increase becoming effective 61 days after notice.

Industry Context

This filing reflects the continued investment strategy of Baker Bros. Advisors, a specialized life sciences investment firm, in the biotechnology and pharmaceutical sector. Their significant stake in Rhythm Pharmaceuticals, a company focused on rare genetic diseases of obesity, underscores their long-term interest in companies with promising therapeutic pipelines.

Stakeholder Impact

• Shareholders: Provides transparency regarding a significant institutional investor's stake and their long-term commitment, potentially signaling confidence.
• Company Management: Awareness of a large, active investor's position and their stated intent regarding control and nominations.

Next Steps

• The Funds may, by written notice to the Issuer, increase or decrease the Maximum Percentage applicable to the Series A Convertible Preferred conversion to any other percentage not exceeding 19.99%.

Key Dates

Recommendation

Keywords

Rhythm Pharmaceuticals, Baker Bros. Advisors, Schedule 13G, Common Stock, Beneficial Ownership, Institutional Investor, Biotechnology, Pharmaceuticals, SEC Filing, Equity Stake, Series A Convertible Preferred Stock