LONDON – Bayer AG is making a major move into gene therapy with the $4 billion acquisition of one of the pioneers of the field, Asklepios Biopharmaceutical Inc. The deal will give the German pharma access to an adeno-associated viral vector platform that has generated multiple commercial and clinical stage assets across a broad range of indications from rare diseases to chronic conditions. The in-house portfolio includes treatments for Pompe and Parkinson’s diseases and congestive heart failure. Asklepios (Askbio) also has spun out programs in hemophilia and Duchenne muscular dystrophy.