In the past several years, there has been much controversy surrounding the possible link between a class of Hepatitis C drugs known as direct-acting antivirals (DAAs) and hepatocellular carcinoma (HCC), or liver cancer. The DAA drugs include Harvoni, Sovaldi, Viekira Pak, Technivie, Olysio, Daklinza, Epclusa, and Zepatier.
In July, I wrote an article on a study that was posted in the July 2017 edition of Gastroenterology that weighed in on this controversy. This study provided additional evidence that DAA treatment does not entail a higher risk of liver cancer.
Although the articles that have been published on the potential link between DAAs and liver cancer tend to conflict with one another concerning whether a definite causal relationship occurs between the two, there are some points of agreement. A recent Medscape article discusses these commonalities in detail, and is the source for the information below.
Firstly, advanced liver disease carries the strongest risk for liver cancer development. One study found that in addition to advanced liver disease, treatment failure was also associated with HCC.
Another study pointed out that patients treated with DAAs are more likely than untreated HCV patients to have conditions that independently increase their risk of liver cancer. Rather than the DAAs themselves, these conditions–such as older age, cirrhosis, and portal hypertension–may be to blame if a patient treated with DAAs experiences an occurrence or recurrence of HCC.
Moreover, additional research suggests that patients who develop HCC after DAA therapy may have had unidentified tumors present before DAA treatment ever occurred. However, some research proposed a theory that DAAs may reduce the immune system’s ability to target certain tumors, which may be responsible for their formation in patients with cirrhosis.
Secondly, many studies show a decreased rate of newly-occurring liver cancer in patients with HCV cirrhosis after sustained virologic response (SVR) due to DAA treatment. See my previous article for a list of some of these studies.
Thirdly, patients with active liver cancer show lower rates of SVR, which means that they are less likely to have the Hepatitis C virus absent from their blood for more than 12 weeks.
Until a definitive causal link between DAAs and liver cancer is–or is not–drawn, we will continue to monitor the medical literature for more information, and report on significant developments.
Written by: Heather Helmendach, Legal Assistant
Law Offices of Thomas J. Lamb, P.A.
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