Gilead Sciences says its second stab at making the U.S.’s first one-pill-once-daily HIV med has fizzled. When Gilead formulated the groundbreaking fixed-dose combo by mixing its Truvada—nukes Emtriva (FTC) and Viread (tenofovir)—with Bristol-Myers Squibb’s non-nuke Sustiva  (efavirenz), Sustiva blood levels were too low. Third try: “bi-layering” the drugs into a pill, still hoping to file for FDA approval by mid-2006.