In the month of March in 2005, the FDA approved entecavir (Baraclude), a nucleoside analogue that demonstrates selective activity against HBV. As with any treatment against chronic HBV, the target of therapy include decreasing active liver inflammation by correcting serologic parameters and liver enzymes in hepatitis, stopping the progression of hepatitis to cirrhosis, as well as preventing the hepatocellular carcinoma, and improving the patient’s quality of life by prolonging survival.
Indication: Entecavir is indicated for adults with chronic HBV who have evidence of viral replication and persistent elevations in serum aminotransferases (ALT, AST) or active disease based on histologic findings. Entecavir is approved for patients with HBeAg-positive, HBeAg-negative, and lamivudine-resistant infection.
Entecavir tablets is an oral analogue of 2´-deoxyguanosine. Following phosphorylation to its active triphosphate form via enzymatic pathways, entecavir is a potent inhibitor of HBV replication. Inhibition of HBV viral production occurs through three mechanisms:
- Priming of HBV-DNA polymerase.
- Reverse transcription of the negative
- strand from the pre-genomic RNA.
- Synthesis of the positive DNA strand.
Entecavir is known to be a weak inhibitory action against mitochondrial DNA polymerase gamma and DNA polymerases alpha, beta, and delta. The net effect of entecavir is thus a reduction in the viral load and prevention of disease progression in infected patients.
The FDA’s approval of entecavir was based on clinical trials in which histologic, virologic, biochemical, and serologic responses were observed after one year of treatment. The study population included nucleoside-naive and lamivudine-resistant patients with HBeAg-positive or HBeAg-negative chronic HBV infection with decompensated liver dis-ease. In terms of co-infection with HBV and HIV, limited data on the safety and efficacy were studied within a small sample population.
Dosage & Administration:
Entecavir is indicated for adults and adolescents 16 years of age or older with chronic HBV infection. The safety and efficacy with entecavir in children have not been established, and the drug is not recommended for children.
And an oral dose of entecavir 0.5 mg once daily is recommended for such patients who are with active Chronic HBV infection and considered new to nucleoside treatment.
Patients who carry a history of hepatitis B viremia, if they are taking lamivudine or if they are known to have lamivudine resistant mutations, should consume an oral dose of entecavir 1 mg once daily.
The tablets should be stored at room temperature. Patients should be advised to take entecavir on an empty stomach before meals.
Side Effects: The most commonly reported adverse drug events (ADEs) associated with entecavir are dizziness, nausea, insomnia, somnolence, headache and fatigue.
Check detailed info on side effects of Entecavir.
