Merck to Acquire Harpoon Therapeutics for $680M

Merck Acquires Pandion Therapeutics

February 25, 2021

Biotechnology

Merck will acquire Pandion Therapeutics for $60 per share in cash, representing an approximate total equity value of $1.85 billion, via a tender offer and subsequent merger. Pandion is a clinical-stage biotechnology company focused on precision immune modulators (TALON platform) with lead candidate PT101 targeting regulatory T cells for autoimmune diseases; the transaction is expected to close in the first half of 2021 subject to customary conditions.

Merck to Acquire Acceleron Pharma Inc for $11.5B

September 30, 2021

Biotechnology

Merck (through a subsidiary) entered into a definitive agreement to acquire Acceleron Pharma Inc for $180 per share in cash, for an approximate total equity value of $11.5 billion. The transaction will be completed via a tender offer followed by a merger, and is expected to close in the fourth quarter of 2021, subject to conditions including regulatory approvals and tender of at least a majority of outstanding shares.

Merck Acquires Prometheus Biosciences

June 16, 2023

Healthcare Services

Merck (MSD outside the United States and Canada) entered into a definitive agreement to acquire Prometheus Biosciences for $200 per share in cash, valuing the equity at approximately $10.8 billion. The acquisition was expected to close in the third quarter of 2023, and Merck later announced completion of the deal, making Prometheus a wholly owned subsidiary.

Johnson & Johnson Completes Acquisition of Halda Therapeutics for $3.05 Billion

December 29, 2025

Healthcare Services

Johnson & Johnson completed its acquisition of Halda Therapeutics OpCo, Inc. for $3.05 billion in cash. The deal brings Halda’s proprietary RIPTAC platform and its clinical-stage prostate cancer therapy HLD-0915, along with earlier-stage RIPTAC candidates for other solid tumors, into J&J’s oncology portfolio.

Gilead Sciences Acquires Immunomedics

September 13, 2020

Biotechnology

Gilead Sciences agreed to acquire Immunomedics for $88.00 per share in an all-cash transaction valuing Immunomedics at approximately $21 billion. The acquisition gives Gilead global rights (outside certain Asian territories) to Trodelvy, an FDA‑approved antibody‑drug conjugate for metastatic triple‑negative breast cancer, and accelerates Gilead’s expansion into oncology.

Halozyme Acquires Antares Pharma for $960M

April 13, 2022

Pharmaceuticals

Halozyme Therapeutics will acquire Antares Pharma for $5.60 per share in cash, valuing Antares at approximately $960 million. The deal, approved unanimously by both boards, is intended to expand Halozyme's drug delivery capabilities by adding Antares' auto-injector platform and commercial specialty products and is expected to be accretive to Halozyme's 2022 revenue and non-GAAP earnings.