An Abbott hepatitis drug has proven effective in small trials. (Tribune file / April 4, 2012)
9:24 a.m. CDT, April 4, 2012
A combination of experimental oral hepatitis C treatments being developed by Abbott Laboratories led to cure rates of more than 90 percent in previously untreated patients, according to data from a small mid-stage study.
The data, to be presented at a major European liver meeting this month, puts Abbott firmly in the crowded race to produce a short duration, interferon-free treatment regimen for the serious liver disease.
"This demonstrates unprecedented cure rates for the most common form of hepatitis C infection. And we were able to achieve those rates with only a 12-week duration of therapy," said Scott Brun, Abbott's divisional vice president for infectious disease development.
Abstracts, or brief summaries, of studies to be presented at the European Association for the Study of the Liver (EASL) meeting in Barcelona were made available on Wednesday.
"At EASL it's going to be very clear that we've reached a really transformational moment for patients with HCV (hepatitis C virus)," Brun said.
The Phase II trial of previously untreated patients, known as Co-Pilot, combined Abbot's protease inhibitor ABT-450 boosted by the antiviral drug ritonavir with its polymerase inhibitor ABT-333 and ribavirin, a drug that is part of all current hepatitis C regimens.
Patients received the combination therapy for 12 weeks and were checked 24 weeks later for signs of the virus in the blood to determine whether there was a sustained virologic response, or SVR. Any patients that achieved an SVR 24 weeks after completing treatment are deemed to be cured.
Eighteen of the 19 patients who received a 250 milligram dose of ABT-450 as part of their combination achieved SVR, or 95 percent, while 13 of 14 patients who got a 150 mg dose of ABT-450 were deemed to be cured, or 93 percent.
In a third arm of the study that involved patients who had failed to be helped by the former standard treatment of interferon and ribavirin, eight of 17 patients achieved SVR for a cure rate of 47 percent.
Abbott is also testing a drug from a promising class known as NS5A inhibitors in various all-oral combinations that it believes may improve cure rates for prior non-responders.
"For a first step it's very encouraging," Brun said of the new data in non-responders. "If you're able to add the potent NS5A inhibitor into the mix we think there's the potential to do even better and that's currently under study."
There were no serious side effects seen in the study, with the most common side effects fatigue, nausea and headache.