Undisclosed Merger Triggers Major Accumulation… Life Sciences Fund Increases Stake in Mirum Pharma

Patrick J. Heron, reported as an insider of Mirum Pharmaceuticals, Inc. (NASDAQ: MIRM), disclosed on January 23 that he acquired a substantial amount of Mirum common stock in the name of his funds through a private transaction in connection with the merger with Bluejay Therapeutics, as well as through a separate share purchase. First, Frazier Life Sciences X, L.P. was allocated approximately $15 million (KRW 200 billion) worth of shares under the Code J transaction as merger consideration. It then further increased its indirect holding by purchasing an additional $9 million (KRW 120 billion) of stock in a Code P transaction.

According to the filing, Frazier Life Sciences X, L.P. now indirectly holds several hundred thousand shares of Mirum common stock, while a separate entity, Frazier Life Sciences IX, L.P., owns several million shares. Heron noted that the partnership’s economic interest in these shares is limited; nonetheless, the filing clearly shows that both funds’ economic exposure to Mirum has expanded significantly through the merger consideration and the subsequent share purchase.

Mirum has drawn the attention of U.S. biotech and pharmaceutical investors thanks to its development pipeline in areas such as rare liver diseases and its recent M&A activity. The Frazier Life Sciences–affiliated funds, for which Patrick J. Heron serves as a partner, specialize in biotech and healthcare investments and are known for their long-term approach to enhancing the clinical and pipeline value of their portfolio companies.