As I wrote here a year ago, Abbott seems to be the company to watch in the race the hepatitis C finish line where a potential $20 billion market awaits.
Recent data from a phase IIb trial are astounding. Abbott's four drug, interferon-free cocktail is turning hepatitis C into the New York Yankees -- impotent and powerless. There are a number of other companies getting close (Gilead, in particular), but I wouldn't bet against the folks from Chicago.
The four-drug cocktail they are testing has all the right ingredients:
A protease inhibitor, which, if approved will be the third drug in this class.
A polymerase inhibitor, which blocks viral replication by a different mechanism -- preventing the viral RNA from being duplicated, minimizing resistance and increasing efficacy.
Ribavirin--an old drug that inhibits viral replication (by an unknown mechanism) and is used in conjunction with interferon.
Ritonavir-- a clever addition that was originally developed as an HIV protease inhibitor for AIDS. It was not especially good, but it was subsequently discovered that ritonavir increased the blood levels of other HIV protease inhibitors by blocking their metabolism. Ritonavir is referred to as a booster, and just happens to work in a similar manner with hepatitis C protease inhibitors.
The Abbott clinical results read like science fiction. Consider that, as of two years ago, hepatitis C treatment consisted of interferon (a god-awful drug, if ever there were one) and ribavirin. After six months of torture, fewer than half of patients were cured.
How things have changed.
In treatment-naive patients, 76 out of 77 patients attained a sustained virological response (SVR12), defined as having virus levels below the limit of detection for 12 weeks after the cessation of therapy. An SVR24--having undetectable virus levels for 24 weeks-- is now considered to be a cure.
But perhaps more significantly, 93 percent of patients that had previously failed interferon-ribavirin treatment--the most difficult to treat--also attained a SVR12. Prior to this, these patients had to be re-treated with ribavirin and a different type of interferon, with about a 30 percent response rate. There were few other options, with a liver transplant--problematic in its own right--being the last resort.
Of course, phase III trials, with many more patients, are required to confirm the present results, and about half of all drug candidates that get through phase II fail. But based on the magnitude of response so far, I would put my money here. This is an amazing pharmaceutical success story.