The FDA yesterday approved Bristol-Myers Squibb’s and Gilead Sciences Atripla, the first ever once-a-day single tablet regiment to treat HIV as a stand-alone therapy or in combination with other retrovirals. It is the first AIDS treatment to mix drugs made by different manufacturers.Atripla combines Bristol-Myers Squibb’s Sustiva, and Gilead’s Truvada and will be available in the US within seven business days, the companies said.The two companies established their joint venture to develop and commercialize Atripla in December 2004.sThe FDA cleared the Atripla in less than three months as part of a push to introduce treatments that combine already-approved HIV drugs.