Darunavir: in treatment-experienced pediatric patients with HIV-1 infection

Darunavir is a nonpeptidic HIV type 1 (HIV-1) protease inhibitor (PI) that binds with high affinity to the HIV-1 protease, including multi-drug resistant proteases. This drug is highly potent against a range of laboratory strains and clinical isolates of wild-type and multidrug-resistant HIV and has limited potential to cause cytotoxicity. Darunavir did not display cross-resistance with other PIs in vitro. The coadministration of a low boosting dose of ritonavir with darunavir (boosted darunavir) increases the bioavailablity of darunavir. The drug is also administered together with other highly active antiretroviral agents. The efficacy of twice-daily boosted darunavir (11-19 mg/kg plus ritonavir 1.5-2.5 mg/kg) in treatment-experienced pediatric patients (aged 6-17 years and weighing > or =20 kg; n = 80) was demonstrated in the phase II DELPHI trial, where a virologic response (HIV-1 RNA reduction from baseline of > or =1 log(10) copies/mL) at week 24 (primary endpoint) was achieved in 74% of patients, and 88% of these patients sustained this level of response at week 48. Boosted darunavir was generally well tolerated in the DELPHI trial, with a similar profile to that observed in adults. The mean triglyceride level at week 48 was lower than that at baseline, and cholesterol levels increased slightly but remained within the normal range.