BOSTON -- An investigational combination treatment appears to allow difficult-to-treat hepatitis C virus-infected patients to attain a sustained virologic response with or without the addition of ribavirin, researchers reported here.
In the multi-arm phase II C-WORTHY trial, vice president of the Texas Liver Institute, San Antonio, reported:
- 28 of 31 cirrhotic patients naive to antiviral therapy -- 90% -- treated for 12 weeks with the fixed dose combination of grazoprevir 100 mg plus elbasvir 50 mg once daily plus ribavirin achieved the goal of sustained virologic response at 12 weeks (SVR12). There were two later relapses in this group.
- 28 of 29 similar patients -- 97% -- treated for 12 weeks with the dual investigative drug without ribavirin achieved SVR12. There was one relapse.
- 31 of 32 similar patients -- 97% -- treated for 18 weeks with all three drugs achieved SVR12. There were no relapses in this group.
- 29 of 31 similar patients -- 94% -- treated for 18 weeks without ribavirin achieved SVR12. There were two relapses.
- 30 of 32 null responders with or without cirrhosis -- 94% -- treated for 12 weeks with the three drugs achieved SVR12. There were no relapses.
- 30 of 33 similar patients -- 91% -- treated for 12 weeks with the two investigational drugs achieved SVR12. There were three relapses in this group.
- 33 or 33 null responders with or without cirrhosis -- 100% -- treated for 18 weeks with all three drugs achieved SVR12. There were no relapses.
- 31 of 32 similar patients -- 97% -- treated with the two investigational drugs for 18 weeks achieved SVR12. There were no relapses.
"High efficacy was observed regardless of the presence or absence of ribavirin or extended treatment duration from 12 weeks to 18 weeks," Lawitz said in his oral presentation during a special hepatitis plenary session at the annual meeting of the American Association for the Study of Liver Diseases.
Session moderator professor of internal medicine at the University of Michigan, Ann Arbor, told Ƶ, "The data is impressive. It is going through phase III clinical trials so we will have to see what those results look like. If the phase II results are confirmed, the treatment will be approved. I don't think we can say that one regimen will be superior to another, but it is comparable to other treatments we have seen. That means that we have more choices. If we have more choices, then maybe the prices will come down a bit through competition. That's what we all hope."
The C-WORTHY was a randomized, dose response, parallel-group, multiple-site, double-blind clinical trial comparing diverse patient populations exposed to different durations of treatment of grazoprevir/elbasvir with or without ribavirin in patients with chronic hepatitis C virus infection.
In C-WORTHY Parts A and B which were presented at AASLD, 471 patients with chronic hepatitis C virus genotype 1 infection were enrolled and randomized. The research was published online in The Lancet simultaneously with presentation at the meeting.
Grazoprevir/elbasvir (formerly known as MK-5172/MK-8742 consists of grazoprevir, an oral, once-daily hepatitis C virus NS3/4A protease inhibitor, and elbasvir, an oral, once-daily hepatitis C virus NS5A inhibitor.
The treatment naive patients in the study arms were about 58 years old; the treatment experienced null responders were about 54 years of age. There were more men than women in the study, and more than 90% of the patients in the study arms were white. Almost all the patients in the treatment naive population had cirrhosis (one patient did not). About 35% of patients who were null responders had cirrhosis.
Adverse events were infrequent. Lawitz said the treatment was well-tolerated. He noted that more adverse events were noted when ribavirin was added to the treatment regimen.
Merck plans to submit the New Drug Application to the FDA for grazoprevir/elbasvir in 2015.
Disclosures
The study was sponsored by Merck.
Lawitz disclosed relevant relationships with AbbVie, Achillion Pharmaceuticals, Boehringer Ingelheim, Bristol-Myers Squibb, Gilead Sciences, GlaxoSmithKline, Idenix Pharmaceuticals, Intercept Pharmaceuticals, Janssen, Merck, Novartis, Presidio, Roche, Santaris Pharmaceuticals, Vertex, Kadmon, BioCryst, Biotica, Enanta and Theravance.
Lok disclosed relevant relationships with Gilead, Immune Targeting System, MedImmune, Arrowhead, Bayer, GlaxoSmithKline, Janssen, Novartis, ISIS, Tekmira, Abbott, Bristol-Myers Squibb, Merck, Roche and Boehringer.
Primary Source
American Association for the Study of Liver Diseases
Source Reference: Lawitz E, et al "Efficacy and safety of MK-5172 and MK-8742 ± ribavirin in hepatitis C genotype 1 infected patients with cirrhosis or previous null response: Final results of the C-WORTHY Study (Parts A and B" AASLD 2014; Abstract 196.