The US Food and Drug Administration (FDA) has issued a warning about
the risk of serious liver injury in people with hepatitis C after starting
recently approved direct-acting antiviral regimens that contain a hepatitis C virus protease inhibitor. The
drug regimens are Zepatier
(grazoprevir/elbasvir), Mavyret (glecaprevir/pibrentasvir) and Vosevi
(sofosbuvir, velpatasvir and voxilaprevir).
FDA has received 63 reports of cases in which
people with hepatitis C suffered worsening liver function or liver
failure.
In many of the reported cases, liver failure occurred in
people who had signs and symptoms of moderate to severe liver impairment
(Child-Pugh B or C) or other serious liver problems and should not have been
treated with these medicines.
Glossary
- compensated cirrhosis
The earlier stage of
cirrhosis, during which the liver is damaged but still able to perform most of
its functions. See also ‘cirrhosis’ and ‘decompensated cirrhosis’.
In some cases, people were reported to have no cirrhosis
or compensated cirrhosis with mild liver impairment (Child-Pugh A) despite
having evidence of decreased platelets at baseline or an increase in the
pressure within the portal vein that carries blood from the digestive organs to
the liver.
In addition, some cases had other significant pre-existing
risk factors such as liver cancer, alcohol abuse, or serious medical illnesses
associated with serious liver problems.
These factors may have contributed to clinical worsening of
liver function or liver failure during treatment with these hepatitis C
medicines. In most cases, liver failure or decompensation typically occurred
within the first 4 weeks of starting treatment.
FDA says that doctors can continue prescribing the drugs to
people with mild cirrhosis (Child-Pugh A) but should monitor patients closely,
especially if they are abusing alcohol or have liver cancer (hepatocellular
carcinoma).
The agency emphasises that these medicines have been widely
used and are safe and effective in people with no or mild liver impairment.
To put the number of cases of liver injury in context, FDA
reports that 83,000 people in the United States underwent treatment for
hepatitis C with one of the medications in 2018.