In our October 15 Dispatch, we reported on an early breakthrough antiviral drug combination developed for oral treatment of patients infected with the hepatitis C virus (HCV). The experimental drug RG7128 was predicted to clear HCV infection in 8-12 weeks with minimal signs of the relatively (very) unpleasant side effects of current treatments, or drug resistance.
Whomever said less is more must not have been an HCV drug researcher. This week, we report on another new HCV drug — Vertex Pharmaceuticals’ telaprevir. The latest in the HCV drug pipeline, telaprevir has an added bonus that RG7128 does not: It treats HCV infection in African Americans, a group that traditionally doesn’t respond to other therapies, with a significantly higher success rate. Telaprivir is likely to be the first specific, small-molecule HCV inhibitor on the market, with approval expected later this year.
“African-Americans are less responsive to HCV treatment and exhibit a lower rate of viral clearance than Caucasians to traditional HCV therapy, so this is an impressive breakthrough,” notes ACSH’s Dr. Josh Bloom. “A new effective drug is needed since current therapies have low response rates and difficult-to-tolerate side effects, which is why many people don’t continue with treatment.”
Approximately three million people in the U.S. have HCV, which is generally acquired by sharing contaminated needles or through sexual transmission, especially among men who have sex with men.
“HCV has four times the global prevalence of AIDS,” Dr. Bloom reminds us. “It’s a latent, silent killer. People can have HCV for up to 25 years and not know about it until one day their liver cells run amok and they need a liver transplant."
“But the only downside of telaprevir is that patients need to take it in addition to the standard of care treatment, which sounds expensive, and the side effects remain a problem, despite the increased efficacy and reduced treatment time,” says ACSH’s Susan Ingber.
Still, Dr. Bloom says telaprevir is an amazing success story, and any new HCV drug will need to supplemented with traditional therapy, at least for a while.