Health and Disability

Haemophilia A is a rare genetic disorder that prevents blood clotting. Patients receive lifesaving infusions of clotting factors, but development of inhibitors in many of those being treated interferes with efforts to control their bleeding.

With the market for haemophilia medications expected to grow to $11 billion next year, Roche's ACE910 drug is closely watched because it could change the way the disease is treated.

"FDA has granted breakthrough therapy designation for ACE910, recognising an unmet need for patients with inhibitors and the promise of these early data," Sandra Hornung, Roche's chief medical officer, said in a statement.