Gilead Sciences and partners Bristol-Myers Squibb and Merck & Co have filed for approval of their triple HIV therapy Atripla in the European Union.

Atripla, already given a green light in the USA, is the first once-daily, triple therapy for HIV-1 that is delivered in a single tablet, and combines B-MS Sustiva (efavirenz) and Gilead's Emtriva (emtricitabine) and Viread (tenofovir). The companies hope that Atripla’s convenience – and the fact that it incorporates one of the most widely-used antiretroviral regimens for newly-diagnosed HIV patients – will make it the cornerstone of HIV therapy.

Gilead and B-MS recently signed an agreement with Merck to help market Atripla in Europe, because the latter company has certain rights to Sustiva outside the USA. The application has been filed jointly by the companies through a newly-established, three-way joint venture based in Ireland.

Gilead already sells a combination product, Truvada, containing emtricitabine and tenofovir, which is on track to achieve $1 billion-plus in sales this year. Meanwhile GlaxoSmithKline sells a triple therapy product called Trizivir (zidovudine, lamivudine and abacavir) that is dosed twice a day and made $550 million in 2006.

Atripla was approved by the US Food and Drug Administration in July.