Merck’s Zepatier (Elbasvir and Grazoprevir) shows superiority on efficacy and safety endpoints

14th April 2016 (Last Updated April 14th, 2016 18:30)

Merck has reported that its Zepatier (Elbasvir and Grazoprevir) showed superiority on efficacy and safety endpoints compared to sofosbuvir plus peginterferon and ribavirin treatment regimen in a Phase 3 trial.

Merck has reported that its Zepatier (Elbasvir and Grazoprevir) showed superiority on efficacy and safety endpoints compared to sofosbuvir plus peginterferon and ribavirin treatment regimen in a Phase 3 trial.

The company's comparative, Phase 3, open-label clinical trial evaluated the efficacy and safety of Zepatier (Elbasvir and Grazoprevir) 50mg/100mg tablets versus a regimen of sofosbuvir 400mg tablets plus peginterferon and ribavirin (pegIFN/RBV) in treatment-naïve and pegIFN/RBV treatment-experienced patients with chronic hepatitis C (HCV) genotype (GT) 1 or GT4 infection.

In the full analysis set (FAS), the efficacy endpoint of sustained virologic response (SVR) 12 weeks after the completion of therapy was achieved in 99% (128/129) of patients receiving Zepatier for 12 weeks versus 90% (114/126) of patients receiving sofosbuvir plus pegIFN/RBV for 12 weeks.

The study's safety endpoint was the regularity of pre-specified safety events focusing on tolerability, hematologic side effects, and liver-related laboratory abnormalities.

"Merck's Zepatier is a once-daily, fixed-dose combination tablet indicated with or without RBV for treatment of chronic HCV GT1 or GT4 infection in adults."

Zepatier was approved by the US Food and Drug Administration (FDA) in January, based in part on prior studies from the Phase 3 programme.

Merck's Zepatier is a once-daily, fixed-dose combination tablet indicated with or without RBV for treatment of chronic HCV GT1 or GT4 infection in adults.

C-EDGE Head-to-Head, which is a comparative Phase 3, randomised, open-label, parallel-group trial conducted at multiple sites in the European Union, Norway and Turkey, was designed to evaluate the efficacy and safety of 12 weeks of Zepatier (Elbasvir and Grazoprevir) versus a 12 week treatment regimen of sofosbuvir plus pegIFN/RBV.

The study randomised 255 GT1- or GT4-infected patients to 12 weeks of treatment with either Zepatier (Elbasvir and Grazoprevir) 50mg/100mg tablets (n=129) or Sofosbuvir 400mg tablets plus pegIFN/RBV (n=126).

Overall, at baseline, 17% of patients had compensated cirrhosis; 67% had HCV RNA greater than 800,000 IU/mL; 99% were white; 78% had IL28B non-CC genotype; and around 25% had failed prior treatment with pegIFN/RBV (10% prior null-responders, 5% prior partial-responders, 10% prior relapsers).

In the FAS, the efficacy analyses showed superiority of Zepatier compared to Sofosbuvir plus pegIFN/RBV, as measured by SVR12.

Higher SVR rates were observed among those receiving Zepatier (Elbasvir and Grazoprevir) in subgroups of patients who had previously experienced a non-response to pegIFN/RBV therapy and in those with cirrhosis, higher baseline viral load, or IL28B non-CC genotype.

In the Zepatier group, one patient discontinued from the trial after completing treatment and there were no virologic failures reported in the Zepatier group.

In the sofosbuvir plus pegIFN/RBV group, virologic failure occurred in 11 patients (9%) and one patient discontinued from the trial after the first week of treatment.