People taking boosted protease inhibitors as a component of a combination antiretroviral (ARV) regimen have the best long-term response to Norvir (ritonavir)-boosted Prezista (darunavir), aidsmap reports.

Norvir is used as an adjunct medication that boosts the drug levels of protease inhibitors.

Publishing their findings in HIV Medicine, researchers from the EuroSIDA study researched 5,678 people who started antiretroviral (ARV) treatment with Norvir-boosted Prezista, Norvir-boosted Reyataz (atazanavir) or Kaletra (lopinavir/ritonavir) between 2000 and 2013.

The study authors conducted separate analyses for the 8 percent of participants who were starting ARVs for the first time, the 44 percent of participants who switched from a different regimen when they had a viral load of 500 or lower and the 48 percent of participants who switched ARVs with a viral load above 500.

In all subgroups, the average time before participants experienced virological failure (two consecutive viral loads higher than 200) was longer among those taking boosted Prezista compared with those taking boosted Reyataz; both these pairings were superior to Kaletra on this count.

After adjusting the data to account for various factors, the investigators found that the risk of virological failure in those starting ARVs for the first time was similar regardless of which boosted protease inhibitor regimen they took. Otherwise, the risk of virological failure in both groups that switched ARVs was lower for those taking boosted Prezista compared with those taking boosted Reyataz, which in turn was lower than for those taking Kaletra.

To read the aidsmap article, click here.

To read the study abstract, click here.