A new study has found that treating and curing hepatitis C virus (HCV) with direct-acting antiviral (DAAs) drugs is associated with a 71% reduced risk of death among those with a history of successfully treated hepatocellular carcinoma (HCC), the most common form of liver cancer.

This new study built upon a December 2018 study by the same research team that found that DAA treatment was not associated with recurrence of liver cancer.

The new study appears to refute previous research that suggested that DAAs may actually increase health risks for people with HCV and a history of liver cancer. The argument was that HCV, while being highly harmful, activates the immune system in a way that helps impede the recurrence of liver cancer.

The authors of the new study—researchers with the University of Texas Southwestern Liver Tumor Program, led by Singal, an associate professor of internal medicine, and Caitlin Murphy, MD, an assistant professor of population and data sciences and internal medicine—published their findings in the journal Gastroenterology.

The investigators conducted a retrospective cohort study of 797 people with HCV-related liver cancer who received successful treatment for the cancer from January 2013 through December 2017 at 31 health care systems throughout the United States and Canada.

A total of 383 (48.1%) of the study members received DAA treatment and 414 (51.9%) did not. Among those who were treated, 43 people died during 941 cumulative years of follow-up, compared with 103 deaths during 527 cumulative years of follow-up among those who did not receive DAAs.

After adjusting the data to account for various factors, the study authors found that DAA treatment was associated with a 46% reduced risk of death during follow-up, and that achieving a sustained virologic response 12 weeks after completing DAA therapy (SVR12, considered a cure) was associated with a 71% reduced mortality risk. Those who were treated with DAAs but not cured received no apparent reduction in their risk of death.

“Not only are these drugs safe in this patient population, but we have now demonstrated that they are helpful,” said study leader Amit Singal, MD, said in a press release. “Our study changes the paradigm from you could treat a patient’s hepatitis C to you should treat it.”

To read the study abstract, click here.