Roche believes ownership of danoprevir will speed development of combination therapies.

Roche is paying InterMune $175 million to acquire full worldwide development and commercialization rights to the Phase II-stage hepatitis C (HCV) drug, danoprevir (RG7227/ITMN-191). The firms had been co-developing the protease inhibitor under an agreement signed in 2006. Danoprevir is in Phase II clinical development both as monotherapy and in combination with Pegasys (pegylated interferon alfa-2a) and Copegus (ribavirin).

“Danoprevir has demonstrated strong early clinical efficacy even in difficult-to-treat patient populations,” states Dan Zabrowski, global head of Roche partnering. “Having full ownership of danoprevir increases our ability to rapidly develop combinations of our own hepatitis C compounds with molecules from other companies to maximize patient benefit.”

Roche’s existing marketed products for HCV include Roferon-A (interferon alfa 2a) and Pegasys (pegylated interferon alfa 2a), which is the standard of care for the disease, the firm claims. A nucleoside polymerase inhibitor, RG7128, is currently in Phase IIb trials for treating chronic HCV infection. RG7128 is being developed in partnership with Pharmasset.

Pegasys was Roche’s fourth best-selling pharmaceutical in the first six months of 2010 (to June 30), achieving sales of CHF 869 million (about $891 million), up 5% on the same period last year in local currencies, and representing 4% of the firm’s overall pharmaceutical sales.