Drugmakers Gilead Sciences and Bristol-Myers Squibb earlier this month announced success in combining their drugs Sustiva, Viread, and Emtriva into a single pill that is taken just once per day. Now a study in The New England Journal of Medicine shows that this simplified regimen is more effective at controlling HIV in treatment-naive patients than even the current gold standard of nonnucleoside reverse transcriptase inhibitor-based therapy.
Lead by researchers at Johns Hopkins University, the study showed that the Sustiva-Viread-Emtriva combination did a better job of reducing HIV viral levels and increasing CD4-cell counts after one year of treatment that the gold-standard combination of Sustiva plus Retrovir and Epivir. Also, fewer individuals on the one-pill regimen dropped out of the study due to adverse events.
Both nonnucleoside-based regimens are currently recommended by the Department of Health and Human Services for the treatment of HIV-positive adults just beginning antiretroviral therapy. But the current study of 517 treatment-naive HIV patients is the first to directly compare the two.
Study data showed that 84% of those taking the Sustiva-Viread-Emtriva combination pill were able to maintain an HIV viral load below 400 copies per milliliter of blood, compared to 73% of those on the Sustiva-Retrovir-Epivir combination. About 80% of those in the Sustiva-Viread-Emtriva arm suppressed HIV levels even further, to below 50 copies, compared to 70% of those taking Sustiva-Retrovir-Epivir.
Patients taking the one-pill combination also posted a mean increase in CD4-cell count of 190 cells, compared to a 158-cell increase among those taking Sustiva-Retrovir-Epivir.
Only 10 of the 257 patients (about 4%) taking Sustiva-Viread-Emtriva dropped out of the study due to adverse events, compared to 23 of the 254 (about 9%) of those taking Sustiva-Retrovir-Epivir.
Anecdotal data also suggested that fat loss from the extremities, a common side effect of antiretroviral therapy, occurred less often among patients in the single-pill regimen arm of the study. But the researchers say that because they did not collect body-fat measurements of the study subjects before beginning drug treatment they cannot quantify their observations.
Because the single-pill combination was shown to be more effective than Sustiva-Retrovir-Epivir combination, and in light of the ease of one-pill, once-daily dosing, the researchers say it is likely the Sustiva-Viread-Emtriva combo pill will be favored by many HIV doctors and patients when it becomes available. Officials at Gilead and BMS say they plan to submit a marketing application to the Food and Drug Administration this spring. If approved, the single-pill regimen could be available in the United States by the end of the year. (Advocate.com)
