Pfizer announced in March that it has halted the development of its experimental oral hepatitis C (HCV) drug PF-00868554, or filibuvir. The drug was in mid-stage clinical testing. Filibuvir is a non-nucleoside polymerase inhibitor, a class of drugs designed to help eliminate HCV.
“We continue to prioritize our [research and development] capital allocation to drive the next wave of innovative medicines and vaccines that bring benefit to patients and value to health care systems around the world,” said Victoria Davis, a Pfizer spokeswoman.
Pfizer was one of several companies developing new, all oral regimens, alternatives to the existing standard of treatment for HCV--weekly injections of pegylated interferon (peg-IFN) and a daily ribavirin (RBV) oral pill. This regimen is not ideal, as nearly 50% of patients do not respond to it. In addition, those who do respond often experience debilitating side effects that can last the duration of the treatment—either 24 or 48 weeks. Pharmaceutical companies are experimenting with interferon-free regimens to see if they can eliminate some of the challenging side effects.
Source: The Wall Street Journal, March 8, 2013