144-Week Data from Gilead's Study 934 Comparing Truvada(R) to Combivir(R) Both in Combination...

SYDNEY, Australia -- Gilead Sciences, Inc. (Nasdaq:GILD) today announced the presentation of 144-week data from an ongoing clinical trial, Study 934, comparing a once-daily regimen of Truvada([R]) (emtricitabine and tenofovir disoproxil fumarate) and Sustiva([R]) (efavirenz) to a twice-daily regimen

of Combivir([R]) (lamivudine/zidovudine) with Sustiva once daily in treatment-naive adults with HIV. Data were presented by Jose Arribas, MD, of the University Hospital La Paz, Madrid, Spain at the 4th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention taking place July 22-25 in Sydney, Australia (Poster #WEPEB029).

Study 934 is an ongoing Phase III, open-label clinical trial in the United States and Europe. Truvada is a fixed-dose once-daily tablet containing Gilead's Viread([R]) (tenofovir disoproxil fumarate) and Emtriva([R]) (emtricitabine). At study initiation, patients received Viread and Emtriva with Sustiva. At week 96, which coincided with commercial availability of Truvada in the United States, all patients receiving Viread, Emtriva and Sustiva were switched to receive a simplified regimen of Truvada and Sustiva. Truvada is currently the most commonly prescribed nucleoside backbone for combination HIV therapy in the United States.

Truvada and Sustiva are also available in the United States as the fixed-dose product Atripla[TM] (efavirenz 600 mg/ emtricitabine 200 mg/ tenofovir disoproxil fumarate 300 mg), through a U.S. joint venture between Bristol-Myers Squibb Company and Gilead Sciences. Atripla was approved in the United States on July 12, 2006.

"These data demonstrate the safety and efficacy profile of the components of Atripla over three years," commented Dr. Arribas. "As the treatment landscape for HIV improves and patients live longer, the importance of a proven and durable first-line regimen with simple dosing is critical."

Study 934 Results

Study 934 is a Phase III, open-label, non-inferiority study that enrolled 517 HIV-infected patients in the United States and Europe. Two patients were protocol violations and six never received drug, resulting in an intent to treat population of 509 patients. The study's primary endpoint was at 48 weeks and the study has continued through 144 weeks. Twenty-two patients with baseline non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations and 31 patients who completed week 48 and week 96 of the study with HIV RNA (viral load) less than 400 copies/mL but did not consent to participate after week 96 were excluded from the week 144 efficacy population. Participants were originally randomized to receive Viread 300 mg, Emtriva 200 mg and Sustiva 600 mg, all dosed once daily, or Combivir twice daily and Sustiva 600 mg once daily. At study entry, patients were treatment-naive, had HIV RNA greater than 10,000 copies/mL and any CD4 cell count. At week 96, patients receiving Viread, Emtriva and Sustiva were switched to a regimen of Truvada/Sustiva.