Global Healthcare Fund Acquires Additional $30 Million in U.S. Rare Disease Biotech Stocks

On January 23, according to a U.S. Securities and Exchange Commission filing, Frazier Life Sciences X—a fund managed by Patrick J. Heron, a director of rare-disease biopharma Mirum Pharmaceuticals, Inc. (NASDAQ: MIRM)—acquired Mirum common shares through a private transaction and open-market purchases. The filing states the fund now indirectly holds approximately $24 million worth of shares—about $15 million in merger consideration for Bluejay Therapeutics and roughly $9 million in additional market purchases, equivalent to around KRW 30 billion. After this transaction, Frazier-affiliated funds’ indirect stake in Mirum has grown to roughly 4 million shares, significantly increasing their economic interest in the company.

On January 26, Mirum officially announced the completion of its acquisition of Bluejay Therapeutics, securing global rights to brelovitug, a late-stage clinical antibody therapy targeting chronic hepatitis D virus (HDV) disease. At the same time, the company closed a private placement raising approximately $268.5 million (about KRW 350 billion) from existing and new healthcare investors, ensuring funding for post-acquisition development and commercialization.

Mirum is a U.S. biotechnology company with approved treatments for rare liver diseases, including Livmarli for Alagille syndrome and progressive familial intrahepatic cholestasis, as well as bile-acid metabolism disorder therapies Cholbam and Ctexli. The company concentrates its pipeline on rare diseases—such as cholestatic liver disorders and HDV—where treatment options remain limited.