It’s been an unusually good week for people with hepatitis C — even those for whom current treatments have failed.
Not one, but two effective new hep C treatments got a strong endorsement from an FDA advisory panel. Both drugs — Merck’s Victrelis (boceprevir) and Vertex’s telaprevir (no brand name at this writing) should soon get full FDA approval.
Right now, only about half of people who undergo hep C treatment get cured (defined as a “sustained viral response,” or hep C virus levels too low to detect). Cure rates are particularly low for people infected with the strain of the virus most common in the U.S. For reasons that are not entirely clear, black people also have lower cure rates.
About two-thirds of people are cured when either of the new drugs is added to current treatment. The telaprevir combination takes six months — half the time of current treatment — while Victrelis treatment lasts eight to 12 months.
As usual in the world of hepatitis C treatment, there are serious downsides to both drugs. The biggest downside is that people who take them still have to take the standard treatment of alpha interferon and ribavirin. Taking these drugs is like having a bad case of the flu that lasts for months.
Unfortunately, the combination of standard treatment with either of the new drugs is even harder to take. Each drug adds to the anemia from the interferon/ribavirin combo. Some 40% of people taking Victrelis get so anemic they need expensive doses of the anti-anemia drugt erythropoietin. And a nasty rash is a common side effect with telaprevir.
The two drugs work in essentially the same way. Both are protease inhibitors, which means they attack a hepatitis C virus (HCV) enzyme that is essential for the virus to make new copies of itself. Each of the drugs brings virus replication to a near halt.
But when used alone, HCV quickly becomes resistant to each of the new drugs. That’s why they have to be given in combination.
So which is better, Victrelis or telaprevir? The FDA panel was careful not to speculate — and don’t hold your breath for a head-to-head study. Both drug companies plan big marketing campaigns. Financial analysts currently speculate that Vertex will grab a bigger market share.
Meanwhile, people with hep C wonder when they’ll see the really big breakthrough everyone is waiting for — a drug combination that works for nearly everyone and which does not require either interferon or ribavirin.
Such treatments are in the pipeline. Some experts say they may come in as few as two or three years, while others say it will be a decade before they’re finally here. What is for sure is that telaprevir and Victrelis are just the first in what is hoped will be a long line of treatment options for people with the deadly hepatitis C virus.