By Colin Kellaher 



  Bristol Myers Squibb Co. on Monday said it agreed to buy Forbius, a clinical-stage protein-engineering company that designs and develops biotherapeutics for the treatment of cancer and fibrotic diseases. 


  Financial details weren't disclosed, but the New York biopharmaceutical company said it would make an upfront payment for Forbius, along with future success-based milestone payments. 


  Bristol Myers said Forbius has developed a portfolio of inhibitors of TGF-beta 1 & 3, which are key mediators of immunosuppression and fibrosis. 


  Bristol Myers said it plans to initially focus research and development efforts of AVID200, Forbius's lead investigational asset in oncology, adding that it may consider advancing the asset in other disease areas, such as fibrosis. 


  Prior to closing, expected in the fourth quarter, Forbius will transfer its non-TGF-beta assets to a newly formed private company, which will be retained by its existing shareholders. 


  Write to Colin Kellaher at colin.kellaher@wsj.com