The US Food and Drug Administration has approved a new once-daily extended release formulation of nevirapine, known as Viramune XR.
The new 400mg tablet will provide an alternative to the
current twice-daily dosing schedule, and can be taken without or without food.
Patients who start treatment with Viramune XR will need to take a 14-day lead-in dose of 200mg of immediate release nevirapine in order to reduce the risk of rash, a common side-effect during the first few weeks of nevirapine treatment.
Treatment with Viramune
XR should not begin until rash has gone away, and if a rash persists for more
than one month an alternative antiretroviral should be used.
Patients already on a regimen of immediate-release Viramune twice daily in combination with other antiretroviral agents can be switched to Viramune XR 400 mg once daily without the 14-day lead-in period of immediate-release Viramune.
Viramune XR was licensed on the basis of results from the VERxVE study, a randomised comparison of immediate-release twice-daily dosing and once-daily dosing with Viramune XR. The 48-week results, presented last year at the 18th International AIDS Conference, showed no significant difference in rates of viral suppression or adverse events between the two formulations.
Nevirapine is not suitable for men with CD4 counts above 400 cells/mm3 or women with CD4 counts above 250 cells/mm3, due to the increased risk of serious and life-threatening hepatotoxicity, unless the benefit of treatment with the drug is considered to outweigh the risk of serious toxicity.