Merck: Results of Phase 3 Study of Investigational Chronic Hepatitis C Therapy

October 6, 2015 Off By Dino Mustafić

Merck has announced the publication of results from C-SURFER, the first Phase 31 clinical trial to investigate an all-oral, ribavirin-free chronic hepatitis C virus (HCV) treatment regimen in treatment-naïve and treatment-experienced patients with advanced chronic kidney disease (CKD) stages 4 or 5 and chronic HCV genotype 1 (GT1) infection.

Data from the Phase 3 clinical trial evaluating the investigational, once-daily treatment regimen of elbasvir (50mg)2 and grazoprevir (100mg)3 in patients with advanced CKD were published online in the medical journal The Lancet. Data from this study were initially presented at The International Liver CongressTM 2015 in April 2015.

“People with advanced chronic kidney disease represent an important segment of the chronic hepatitis C patient population,” said Dr. Howard Monsour, Jr., chief of hepatology, Houston Methodist Hospital.

“The publication of this study details the evidence supporting a potential future treatment option for these patients who are currently underserved.”

Merck explains that the peer-reviewed, published results show that 12 weeks of therapy with elbasvir plus grazoprevir in patients with chronic HCV GT1 infection and advanced CKD resulted in high rates of sustained virologic response 12 weeks after the completion of treatment (SVR12). High rates of SVR were achieved regardless of patient characteristics in this study, including African-American patients, patients receiving hemodialysis and patients with the IL28B non-CC genotype. Among those receiving elbasvir plus grazoprevir in the primary analysis population, 99 percent (115/116) achieved SVR12, with one relapse 12 weeks after the end of treatment. In a secondary analysis that included six additional patients excluded from the primary efficacy analysis for non-virologic reasons (study discontinuation unrelated to study drug, loss to follow-up, noncompliance, etc.), 94 percent (115/122) achieved SVR12. Adverse events reported at or above 10 percent frequency in the active and placebo treatment groups included headache, nausea and fatigue; rates in the active treatment group were comparable to those in the group that received placebo for the first 12 weeks.

Merc About Chronic HCV Infection and Chronic Kidney Disease

Chronic HCV infection is both a cause and complication of the treatment of CKD. In patients with CKD, chronic HCV infection is associated with an increased risk of accelerated loss of remaining kidney function, kidney transplant failure and death. Furthermore, patients with chronic HCV infection and advanced CKD represent an unmet need due to a lack of demonstrated HCV treatment options for this group.

Merck About Elbasvir/Grazoprevir

Elbasvir/grazoprevir is Merck’s investigational, once-daily, fixed-dose combination therapy containing elbasvir (HCV NS5A replication complex inhibitor) and grazoprevir (HCV NS3/4A protease inhibitor). Evaluations of elbasvir/grazoprevir for multiple HCV genotypes as part of Merck’s broad clinical trials program include patients with difficult-to-treat conditions such as cirrhosis, advanced chronic kidney disease, HIV/HCV co-infection, inherited blood disorders and those on opiate substitution therapy. In July 2015, the U.S. Food and Drug Administration (FDA) granted Priority Review for the New Drug Application for elbasvir/grazoprevir, with a Prescription Drug User Fee Act (PDUFA) action date of Jan. 28, 2016.

In April 2015, the FDA granted Breakthrough Therapy designation status for elbasvir/grazoprevir for the treatment of patients with chronic HCV GT1 infection with end stage renal disease on hemodialysis, and Breakthrough Therapy designation status for elbasvir/grazoprevir for the treatment of patients with chronic HCV GT4 infection. Breakthrough Therapy designation is intended to expedite the development and review of a candidate that is planned for use, alone or in combination, to treat a serious or life-threatening disease or condition when preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints.