Mersana Therapeutics (MRSN) Soars on Up to $285 Million Day One Biopharmaceuticals Buyout: All the Key News on November 13, 2025
Mersana Therapeutics (NASDAQ: MRSN) is back in the headlines in a big way today after announcing a definitive agreement to be acquired by Day One Biopharmaceuticals in a deal worth up to approximately $285 million. The news has sent MRSN shares rocketing higher and triggered immediate legal and regulatory attention, making this one of the most closely watched biotech deals of the day. GlobeNewswire+2Quiver Quantitative+2 Below is a complete roundup of today’s major developments around Mersana Therapeutics (MRSN) — structured and optimized for readers who find this via Google News or Discover. Today’s Mersana (MRSN) Headlines at a Glance –