Efficacy of a reduced dose of DARUNAVIR/RTV in a cohort of antiretroviral‐naïve and experienced HIV‐infected patients: a medium‐term follow‐up

Background The currently approved dose of darunavir/ritonavir is 800/100 mg once daily for PI‐naïve patients, and 600/100 mg twice daily for PI‐pretreated patients. However, in DRV‐sensitive patients at baseline in the POWER 1/2 trials, similar rates of HIV RNA suppression (1 log reduction) were achieved with doses ranging from 400/100 mg once daily to 600/100 mg twice daily. In previously virologically suppressed patients, a reduced dose of DRV (600/100 QD) is non‐inferior to the standard dose (800 mg QD)[1] and DRV concentrations in plasma and CSF are similar in patients receiving the above different doses [1, 2]. Methods Twelve treatment‐naïve patients were started on darunavir/ritonavir 600/100mg once daily, with TDF/FTC (8) or ABC/3TC (4). Seven patients were switched to darunavir/ritonavir 600/100 mg once daily, with TDF/FTC (2), ABC/3TC (2), NVP (1), AZT/3TC (1). One was on monotherapy with DRV. Seven treatment‐experienced patients were switched to darunavir/ritonavir 600/100 mg once daily, with TDF/FTC (5), ABC/3TC (1), RAL (1). Results Of the 12 naïve patients (mean baseline HIV RNA 134,024 log10 copies/mL, range 4,256‐397,932), 11 had HIV RNA