The Institute for Safe Medicine Practices reviewed 12 months of FDA data and identified hundreds of cases of acute liver failure in patients taking direct-acting antivirals for hepatitis C.
In October, the FDA announced that it was adding a boxed warning to the labels of direct-acting antivirals after identifying 24 cases of hepatitis B reactivation. Three of these patients experienced liver failure.
This prompted the Institute for Safe Medicine Practices to review additional FDA data, thereby identifying 524 cases of acute liver failure in patients taking direct-acting antivirals. Nearly a third of these patients died. Over 40% of cases included encephalopathy.
Paritaprevir combinations were most often implicated (35% of cases), followed by sofosbuvir (33%). Nine out of 10 cases were reported by clinicians as a drug-related adverse event and not the result of hepatitis C progression. The group also found over 1000 cases of severe liver damage that had not yet progressed to liver failure.
The maker of sofosbuvir told the institute that its drug was approved for patients with liver failure, so that could account for some of the cases.