Coverage of 2007 ICAAC
(Interscience Conference on Antimicrobial Agents and Chemotherapy)

September 17–20, 2007, Chicago, Illinois

Prezista performs as well as Kaletra for first line therapy

September 18, 2007

Results were presented at the 47th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) from an ongoing head-to-head study of Prezista (darunavir) boosted with Norvir (ritonavir) compared to Kaletra (lopinavir + ritonavir) in people taking anti-HIV drugs for the first time. The ARTEMIS study compared Prezista taken once a day to Kaletra, which was taken either once or twice a day. Everyone also took the fixed-dose combination of Truvada (tenofovir + emtricitibine/FTC). ARTEMIS included 689 people, which 30% were female and around 45% were either of African of Hispanic descent.

After 48 weeks, 84% of those on Prezista had HIV levels below 50 copies vs. 78% of those on Kaletra. There was a big difference between people taking Kaletra once a day vs. twice a day. Of those taking Kaletra once a day, 71% had HIV levels below 50 copies vs. 81% for those taking it twice a day. The difference in HIV levels between people taking Prezista and those on Kaletra twice a day was statistically insignificant.

Prezista also did significantly better in people who started the study with HIV levels over 100,000 copies/mL. In these people with high viral loads, 79% of people taking Prezista had viral loads below 50 copies at 48 weeks vs. 67% of those on Kaletra. There was virtually no difference seen in people who started treatment with HIV levels below 100,000.

Prezista performed somewhat better in terms of side effects as well. More people taking Kaletra (7% vs. 3%) stopped their regimens due to adverse effects. Most of the side effect problems were nausea, vomiting and increased triglycerides. More people taking Prezista experienced a rash. However, one notable point about the study is that the Meltrex formulation of Kaletra was not used. Though there’s no evidence that Meltrex works better, it is however somewhat less toxic than the version used in the study. This would likely result in fewer side effects and may be comparable to or better than Prezista’s side effects.

Prezista was approved in 2006 for people with extensive treatment experience. These results suggest that Prezista is poised to become a favorable option for first line HIV treatment.