Three Rivers Pharmaceuticals, a privately held firm based in Pennsylvania, obtained the right to sell Infergen in China, beginning March 31, 2009. Infergen, also known as consensus interferon, is a bio-optimized, selective and potent type 1 interferon alpha indicated for patients with chronic hepatitis C. Unlike most forms of interferon, it is not administrated in conjunction with ribavirin. Financial details of the deal were not disclosed.

In December 2007, Three Rivers paid $70.8 million plus up to $20.5 million in two noncontingent payments for the US and Canadian rights to Infergen from Valeant (NYSE: VRX). Infergen was developed by Amgen (NSDQ: AMGN) and approved by the FDA in 1997. The China rights came as part of a package that Three Rivers negotiated for a worldwide license to distribute the drug, with the exception of Japan. Outside of China (and Japan), control of the drug transfers to Three Rivers immediately.

Three Rivers said it would seek marketing partners to distribute the drug outside the US.

Infergen is indicated for the treatment of chronic hepatitis C virus (HCV) infection in patients 18 years of age or older with compensated liver disease who have anti-HCV serum antibodies or the presence of HCV RNA.

Three Rivers also markets ribavirin products and an injected antifungal.