Zepatier (elbasvir, grazoprevir)
Zepatier (elbasvir and grazoprevir) is a fixed-dose combination medication indicated for adults with chronic HCV genotype 1 or 4.1 For some individuals, Zepatier is indicated for use with ribavirin. Zepatier’s main components are direct-acting antiviral medications that act as an HCV NS5A inhibitor (elbasvir) and an NS3/4A protease inhibitor (grazoprevir). There is a potential for hepatitis B reactivation in individuals taking Zepatier who have a history of HBV. It is important to also consult the prescribing information for any medications you are also taking in combination with Zepatier, including ribavirin.2
What are the ingredients in Zepatier?
The active ingredients in Zepatier are elbasvir and grazoprevir.
How does Zepatier work?
Zepatier’s first active ingredient, elbasvir, is a direct-acting antiviral that inhibits HCV NS5A. NS5A is a nonstructural protein made by the HCV virus that is important to the virus’ growth and replication. The exact mechanism by which NS5A works is unknown. The inhibitor works to eliminate these crucial proteins made by the virus utilized for RNA replication and virion assembly. Zepatier’s second active ingredient, grazoprevir, is also a direct-acting antiviral that acts as an HCV NS3/4A protease inhibitor. This protease is an essential enzyme required for viral replication. In theory, by inhibiting this enzyme the virus will be prevented from further growth and reproduction. Many direct-acting antivirals work in this manner, targeting proteins, enzymes, and specific steps in the HCV life cycle.
What are the possible side effects of Zepatier?
Multiple clinical trials evaluated the safety and efficacy of Zepatier. The most common side effects of Zepatier are headache, tiredness, and nausea. For those taking Zepatier and ribavirin together the most common side effects are anemia (low red blood cell count) and headache.
These are not all the possible side effects of Zepatier. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with Zepatier.
Things to note about Zepatier
There is a possibility of HBV reactivation while taking Zepatier if you have a history of HBV. Your provider will administer a blood test before starting Zepatier to monitor your risk of HBV reactivation. Reactivation of HBV could cause serious liver problems including liver failure or death.
When taking Zepatier, there is also a chance of developing severe liver problems. Your provider will monitor your liver function before and during treatment, however, you should contact your provider right away if you notice the following liver-related symptoms:
- Loss of appetite
- Nausea and vomiting
- Yellowing of skin or eyes
- Color changes in stools
Before staring Zepatier talk to your provider if you:
- Have or have had hepatitis B infection*
- Have or have had liver problems other than those related to HCV
- Have any other medical conditions
- Are taking any other medications, supplements, or vitamins
- Are pregnant or are planning to become pregnant. It is not known if Zepatier will affect an unborn baby.
- Are breastfeeding or planning to breastfeed. It is not known if Zepatier can pass through breast milk.
Zepatier is contradicicated for patients with moderate or severe hepatic impairment (Child-Pugh B or C), and/or those taking OATP1B1/3 inhibitors that are known or expected to significantly increase grazoprevir plasma concentrations, strong CYP3A inducers, and efavirenz. If Zepatier is administered with ribavirin, the contraindications to ribavirin also apply.
Individuals are advised to notify their provider immediately if they become pregnant, and to avoid becoming pregnant until 6 months after stopping Zepatier, if taking along with ribavirin.
*Direct-acting antiviral drugs (DAA's) now carry a “Black Box Warning” which is used by the FDA to draw attention to serious or life threatening risks. When DAAs are given to treat HCV patients with HBV co-infections, the HBV can potentially reactivate, even if the patient’s immune system held the HBV in-check prior to treatment.