The boosted protease inhibitor Kaletra (lopinavir/ritonavir) has been approved for once-daily use by treatment-naïve adults in the United States.
Product labels for Kaletra will now state that individuals taking antiretroviral therapy for the first time will be able to take a once-daily dose of the drug following approval by the Food and Drug Administration (FDA).
FDA approval for once-daily use of the drug was based on analysis of two clinical trials (studies N99-056 and M02-418), examining the safety and efficacy of a single daily dose of 800mg lopinavir boosted by 200mg ritonavir against two doses consisting of 400mg lopinavir boosted by 100mg ritonavir. These studies found similar levels of efficacy for the once-daily and twice-daily doses of Kaletra.
In both these studies Kaletra was combined with tenofovir (Viread) and FTC (emtricitabine, Emtriva). In both arms of the study individuals took tenofovir and FTC once daily.
Treatment-naïve patients will now have the option of being prescribed a single daily dose of six Kaletra capsules.
However, once-daily Kaletra is not recommended for treatment-experienced patients. When used once daily, trough concentrations of lopinavir are approximately 60% of the twice-daily dose. Furthermore, there have been no clinical studies looking at the safety and efficacy of once-daily Kaletra in treatment-experienced individuals.
Diarrhoea appears to occur more frequently when Kaletra is used once-daily. In the 418 study 57% of individuals taking the once-daily dose reported diarrhoea compared to 35% of individuals on the twice-daily dose.
Once daily Kaletra should not be taken in combination with efavirenz (Sustiva), nevirapine (Viramune), amprenavir (Agenerase), or nelfinavir (Viracept).