Merck Announces Positive Results for Investigational Hepatitis C Drug

Merck has recently announced positive results from 3 clinical trials of an investigational hepatitis C virus treatment in patients with genotypes 1, 2, or 3.

The drug is a triple-combination treatment called MK-3682B (MK-3682/grazoprevir/ruzasvir). It combines a nucleotide analogue NS5B polymerase inhibitor (MK-3682), a NS3/4A protease inhibitor (grazoprevir, MK-5172) and a NS5A inhibitor (ruzasvir, MK-8408).

In part B of the phase 2 C-Crest 1 & 2 trials, the drug showed a benefit of high rates of sustained virologic response 12 weeks after the end of an 8-week treatment cycle in patients with chronic hepatitis C virus genotypes 1 or 3, according to a press release from Merck.

Findings from this trial also indicated that 12 or 16 weeks of treatment with MK-3682B resulted in high rates of sustained virologic response in patients with genotypes 1, 2, and 3. Part C of the trial found high rates of sustained virologic response at 12 weeks in patients who failed prior treatment with direct-acting antivirals, and interim results from the C-Surge trial showed high rates of sustained virologic response at 8 weeks in these patients.

Part B of C-CREST 1 & 2 evaluated the safety and efficacy of MK-3682B in 24 patients with hepatitis C virus genotypes 1, 2, or 3. Patients with genotype 2 or 3 received the drug with or without ribavirin, and patients with genotype 1 or 2 had not received previous treatment.

The primary endpoint of the trial was the amount of patients who achieved sustained virologic response at 12 weeks, according to Merck.

After 8 weeks of treatment with MK-3682B, 95% of patients with genotype 1, 86% of patients with genotype 2, and 95% of patients with genotype 3 achieved the primary endpoint. A 12-week treatment also resulted in high rates (GT1, 99%; GT2, 97%; GT3, 97%).

The status of cirrhosis was not seen to affect treatment, and no patients experienced virologic failure in patients with genotypes 1 or 2 who received 12 weeks of MK-3582B, Merck said in the press release.

Common adverse events reported in this trial include headache, fatigue, and nausea. Serious adverse events experienced were related to ribavirin use.

“As a scientist and physician who regularly treats patients with chronic hepatitis C, the importance of continuing to research this complex disease and its many complications is evident,” said Eric Lawitz, MD, vice president, scientific and research development, The Texas Liver Institute and clinical professor of medicine, The University of Texas Health Science Center, San Antonio. “The virologic cure rates observed in Part B of C-CREST 1 & 2 clearly demonstrate the potential for MK3 and support further study of this investigational regimen.”