Blueprint Medicines Corporation (NASDAQ: BPMC), a leader in discovering and developing targeted kinase medicines for patients with genomically defined diseases, today announced that it has commenced an underwritten public offering of $150,000,000 in shares of its common stock. In addition, Blueprint Medicines expects to grant the underwriters a 30-day option to purchase up to an additional of $22,500,000 in shares of its common stock in connection with the public offering. All shares of common stock will be offered by Blueprint Medicines.

Blueprint Medicines expects to use the net proceeds of the offering to fund clinical trials for BLU-285 in GIST and SM, to fund clinical trials for BLU-554 in HCC, to fund the completion of its current Phase 1 clinical trial for BLU-667 in non-small cell lung cancer, medullary thyroid cancer and other advanced solid tumors and the initiation of additional clinical trials for BLU-667 in RET-driven cancers, and the balance, if any, to fund working capital, and other general corporate purposes, including ongoing research and pre-commercial planning activities. For both BLU-285 and BLU-554, the clinical trials may include the expansion of the current Phase 1 clinical trials for its targeted indications, registration clinical trials or indication expansion clinical trials.

Goldman, Sachs & Co., Morgan Stanley and Cowen and Company are acting as joint book-running managers for the offering. Raymond James is acting as co-manager for the offering. The offering is subject to market and other conditions, and there can be no assurance as to whether or when the offering may be completed or as to the actual size or terms of the offering.

About Blueprint Medicines

Blueprint Medicines is developing a new generation of targeted and potent kinase medicines to improve the lives of patients with genomically defined diseases. Its approach is rooted in a deep understanding of the genetic blueprint of cancer and other diseases driven by the abnormal activation of kinases. Blueprint Medicines is advancing four programs in clinical development for subsets of patients with gastrointestinal stromal tumors, hepatocellular carcinoma, systemic mastocytosis, non-small cell lung cancer, medullary thyroid cancer and other advanced solid tumors, as well as multiple programs in research and preclinical development.