Flexus Biosciences, Backed by Amgen, Acquired For $1.25 Billion

Flexus Biosciences, which is backed by Thousand Oaks-based Amgen, has been acquired by Bristo-Myers Squibb in a deal worth $1.25 billion. Flexus--which is based in the Bay Area--counts Amgen veterans Terry Rosen and Steve Young among its founders. Flexus Biosciences was venture backed by Kleiner Perkins Caufield and Byers, The Column Group, Celgene, and Amgen, and had just announced a $38M Series B financing in December. Rosen was Vice President, Therapeutic Discovery (TD) at Amgen prior to co-founding Flexus Biosciences.