Baker Brothers Life Sciences Buys 91,806 Madrigal Shares As Reported Stake Reaches 9.99%
Baker-managed funds also hold prefunded warrants and nonvoting preferred stock, with limits on conversion into common shares.
Baker Brothers Life Sciences bought 91,806 shares of Madrigal Pharmaceuticals, which develops treatments for the serious liver disease MASH, on Wednesday and Friday. The purchases prompted a Friday SEC ownership amendment reporting a 9.99% stake for Baker Bros. Advisors LP and the other reporting persons, with eligible warrants and options included.
Life Sciences Adds Common Shares
The buying covered five transactions across the two trade dates. Life Sciences used working capital to buy the shares directly from a broker-dealer in the over-the-counter market.
Baker Bros. Advisors controls investment decisions and voting for Life Sciences and 667. Together, those funds directly held 2,227,287 common shares: 2,032,124 at Life Sciences and 195,163 at 667.
The reported beneficial holding was 2,330,144 shares. That ownership measure includes securities eligible to become common shares and is distinct from the funds' direct common-stock holdings. The amendment said the purchases produced a change of more than 1% in beneficial ownership.
Warrants Carry A 9.99% Limit
The funds also held 2,705,790 prefunded warrants, instruments that can be exercised for common shares. Only 90,417 warrant shares counted in the reported ownership calculation, alongside 4,790 shares available through vested director options.
Warrant exercise is restricted by a 9.99% ownership ceiling. The funds can raise that ceiling to no more than 19.99% by notifying Madrigal, but an increase takes effect only on the 61st day after notice.
The funds' preferred-stock holdings comprised 1,969,797 Series A shares and 400,000 Series B shares. Both classes lack voting rights and convert one-for-one into common shares, subject to 4.99% ownership limits. Those limits currently prevent conversion of either class.
An Investment In Rezdiffra's Business
Madrigal's only approved product is Rezdiffra, a daily pill for adults with MASH and moderate to advanced liver scarring. MASH can progress to cirrhosis, liver failure and liver cancer.
Rezdiffra generated $958.4 million in product revenue in 2025. Sales began in the United States in April 2024 and Germany in September 2025; European approval spans the 27 European Union countries plus Iceland, Liechtenstein and Norway. Madrigal also licenses other MASH drug candidates, including an oral GLP-1 drug, ervogastat and six siRNA programs.
The funds described the holdings as investments. The reporting persons left open further buying or selling based on company prospects, security prices, market conditions and other investment opportunities. They also said they may consider financing suggestions to management and discussions with directors and other investors.
Any additional common shares obtained through the funds' warrants or preferred stock remain subject to the instruments' ownership limits.
Sources
- SCHEDULE 13D/A — Baker Bros. Advisors LP re: Madrigal Pharmaceuticals, Inc. (MDGL) — SEC EDGAR
- SCHEDULE 13D/A Exhibit 99.1 — EXHIBIT 99.1 — SEC EDGAR
- SCHEDULE 13D/A Exhibit 99.2 — EXHIBIT 99.2 — SEC EDGAR
