Products
Telaprevir is commercially available in the form of film-coated tablets (Incivo). It was approved in many countries in 2011.
Structure and properties
Telaprevir (C36H53N7O6, Mr = 679.8 g/mol) is a peptidomimetic and a ketoamide. It exists as a white crystalline powder that is sparingly soluble in water. Telaprevir is converted in the body to the -diastereomer VRT-127394, which is more active than the parent compound.
Effects
Telaprevir (ATC J05AE11) is antiviral. Its effects are due to selective, covalent, and reversible inhibition of NS3/4A serine protease, which plays an important role in viral maturation and thus viral replication. The protease converts the HCV polyprotein into the mature nonstructural proteins NS4A, NS4B, NS5A, and NS5B.
Indications
In combination with peginterferon alfa and ribavirin for the treatment of genotype 1 chronic hepatitis C in adult patients with compensated liver disease.
Dosage
According to the SmPC. Tablets are taken every 8 hours with a meal.
Contraindications
Therapy is contraindicated in hypersensitivity, during pregnancy, in combination with narrow therapeutic range CYP3A substrates, and strong CYP inducers. For complete precautions, see the drug label.
Interactions
Telaprevir is a substrate and an inhibitor of CYP3A and of P-glycoprotein. Corresponding drug-drug interactions are possible (see above).
Adverse effects
The most common possible adverse effects include anemia, rash, thrombocytopenia, lymphopenia, pruritus, and nausea. Rarely, severe and life-threatening skin reactions occurred during treatment.