The United States Food and Drug Administration has approved new dosing for the protease inhibitor darunavir (Prezista) that will allow the drug to be dosed once daily for patients with prior treatment experience, provided they do not have darunavir-associated resistance mutations.
The recommended oral dose for treatment-experienced adult patients with no darunavir resistance associated substitutions (V11I, V32I, L33F, I47V, I50V, I54L, I54M, T74P, L76V, I84V and L89V) is 800 mg Prezista once daily with ritonavir 100 mg once daily and with food.
The recommended oral dose for treatment-experienced adult patients with at least one darunavir resistance associated substitution (V11I, V32I, L33F, I47V, I50V, I54L, I54M, T74P, L76V, I84V and L89V) is 600 mg Prezista twice daily taken with ritonavir 100 mg twice daily and with food.
For antiretroviral treatment experienced patients genotypic testing is recommended. However, when genotypic testing is not feasible, Prezista/ritonavir 600/100 mg twice daily dosing is recommended.
The decision to authorise once-daily dosing for treatment-experienced patients is based on the findings of the ODIN trial, which compared once and twice-daily dosing of darunavir/ritonavir in treatment-experienced patients without darunavir resistance.
Prezista is already approved for once-daily dosing for patients new to HIV treatment in both the United States and the European Union.