Quad Pill Works Over 2 Years (CME/CE)
In pooled results from two randomized clinical trials, treatment with the four-drug, once-daily single tablet (Stribild) continued to show efficacy comparable with other anti-HIV regimens out to 96 weeks, researchers said here.
After 96 weeks, 84% of patients on the 'quad' achieved undetectable suppression of HIV using the 50 copies/mm3 assay compared with viral suppression in 82% of patients on the combination of efavirenz-emtricitabine-tenofovir (Atripla), said David Cooper, MD, professor of medicine at the Kirby Institute, University of New South Wales, Sydney.
At his poster presentation at the International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention, Cooper also noted that at 96 weeks, 83% of patients on the 'quad' were suppressed compared with 82% of those treated with an atazanavir/ritonavir plus emtricitabine-tenofovir (Truvada) regimen.
"Stribild had a robust and durable efficacy through Week 96," Cooper told MedPage Today.
"It was comparable to Atripla and to atazanavir plus Truvada. The effectiveness of Stribild was consistent across all demographic groups and when we stratified for HIV levels and CD4 cell counts."
Efficacy was similar among patients younger than 40 and older than 40; in men and in women; in whites and in nonwhites; in those with baseline HIV RNA levels above 100,000 copies/ml and in those with HIV RNA below 100,000 copies/ml; in those with CD4-positive cell counts 350 cells/mm3 or higher and those in patients with less than 350 cells/mm3; and there was similar efficacy if patients were adherent or less than 95% compliant in taking their medications.
"We think that the overall efficacy, safety and tolerability support the use of this combination as a first line therapy in treatment-naïve HIV patients," Cooper said.
Cooper and colleagues enrolled 701 patients on Stribild; 352 patients to receive Atripla, and 355 to atazanavir/ritonavir.
The patients were about 38 years of age; 90% were men; about 30% were nonwhite. Baseline CD4-positive cell counts were about 380 cells/mm3.
Cooper pointed out that in terms of adverse events, 14% of patients on Atripla experienced abnormal dreams compared with 5% of those on atazanavir/ritonavir and 1% of those on Stribild. Dizziness was reported among 4% of patients on Atripla at 96 weeks compared with about 1% of patients on the other two regimens.
The change from baseline in CD4–positive cells counts was similar across the three treatment groups. After 96 weeks, patients on atazanavir/ritonavir plus Truvada achieved a 261 cells/mm3 increase; those on Atripla achieved a 273 cells/mm3 increase; and those on Stribild achieved a 275 cells/mm3 increase, Cooper reported.
"These results are about what we expected to see with this combination product," Julio Montaner, MD, professor of medicine at the University of British Columbia, Vancouver, told MedPage Today.
"These findings are confirming and are reassuring," he said.
Stribild, a combination of the integrase inhibitor elvitegravir, the pharmacologic booster cobicistat, the nucleoside reverse transcriptase emtricitabine and the nucleotide reverse transcriptase tenofovir is approved in the U.S., Europe, Japan, Australia, and elsewhere. In the U.S., however, elvitegravir and cobicistat are not approved yet as individual drugs.
The study was sponsored by Gilead Sciences, Foster City, Calif.
David has disclosed commercial interests with Gilead, Merck, and Bristol-Myers Squibb.
Montaner disclosed his center performs research for Gilead, Merck, GlaxoSmithKline, Bristol-Myers Squibb, and multiple other pharmaceutical companies.
Primary source: International AIDS Society
Source reference:
Cooper D, et al "Subgroup analyses of 96-week efficacy and safety of elvitegravir/cobicistat/emtricitabine/tenofovir DF" IAS
2013; Abstract TUPE281.
