Boosted tipranavir versus darunavir in treatment-experienced patients: observational data from the randomized POTENT...

The POTENT trial compared the safety and efficacy of tipranavir/ritonavir (TPV/r) to darunavir/ritonavir (DRV/r), each with an optimized background regimen (OBR) in triple-class experienced HIV-1-infected patients with resistance to more than one protease inhibitor (PI).

POTENT was a prospective, open-label study of triple-class (PI, non-nucleoside reverse transcriptase inhibitors [NNRTI], nucleoside reverse transcriptase inhibitors [NRTI]), treatment-experienced, HIV-positive patients. Subjects were randomized to either TPV/r (500/200 mg twice daily) or DRV/r (600/100 mg twice daily) on a genotype-guided, investigator-selected OBR. CD4+ counts and HIV viral loads were assayed at key timepoints. The primary endpoint was time to virologic failure (viral load ≥500copies/mL). POTENT was prematurely terminated due to slow enrollment. Thirty-nine patients were treated with either TPV/r (n = 19) or DRV/r (n = 20); 82% were male, 77% White, with mean age of 43.6 years. Mean baseline HIV RNA was 3.9 log(10) copies/mL. Median prior antiretrovirals was 11, with no prior raltegravir or maraviroc exposure. Raltegravir was the most common novel class agent in the OBRs (n = 14 TPV/r; n = 12 DRV/r). In both groups, patients achieved mean viral load decreases ≥2 log(10) copies/mL by week 8, and by week 12 mean CD4+ counts rose by 40-50 cells/mm3. Total observation time was 32 weeks. Drug-related adverse events were reported in 21% (TPV/r) and 25% (DRV/r) of patients.

TPV/r- and DRV/r-based regimens showed similar short-term safety and efficacy. These data support the use of next-generation PIs such as tipranavir or darunavir with novel class antiretroviral agents (integrase inhibitors, CCR5 antagonists, or fusion inhibitors).