People who take hepatitis C virus (HCV) regimens containing Merck’s grazoprevir, including as a component of Zepatier (grazoprevir/elbasvir), have a low rate of hepatocellular carcinoma (HCC, the most common form of liver cancer) during the following years. The authors of a recent analysis found no association between grazoprevir and the risk of liver cancer.
Presenting their findings at the Annual Meeting of the American Association for the Study of Liver Diseases in San Francisco (The Liver Meeting), researchers culled data from a long-term extension study of people with HCV who received a grazoprevir-containing regimen in the Phase II and III trials of the drug’s development program. The participants were followed from 24 weeks after treatment and made clinic visits every six months thereafter for up to five years.
The analysis included 2,435 people who were enrolled in 25 studies. They were followed for 1 to 1,334 days and a median of 545 days.
During this time, 15 people developed liver cancer. This translated to an overall diagnosis rate of 2.77 diagnoses per 1,000 cumulative years of follow-up. The time between the end of therapy and liver diagnosis among those who received such a diagnosis was a median 448 days and ranged between 38 and 934 days.
Respective demographics of the 2,435 people who did not develop liver cancer compared with the 15 who did were as follows: 95.7 percent versus 86.7 percent achieved a sustained virologic response 12 weeks after completing therapy (SVR12, considered a cure); 58 percent versus 73.3 percent were male; 74.5 percent versus 53.3 percent were white, 11.8 percent versus 6.7 percent were Black, 12.1 percent versus 33.3 percent were Asian, and 8.3 percent versus zero were Latino; 74.8 percent versus 60 percent had been treated for the first time in their grazoprevir study; 22.4 percent versus 40 percent had been treated for HCV before; 27.8 percent versus 73.3 percent had cirrhosis when they were treated with grazoprevir; and the median age upon starting treatment was 51.4 years old versus 59.4 years old.