Health stocks were mixed to slightly down with regulatory and clinical updates making a few headlines on Tuesday.

Gilead Sciences ( GILD - Get Report) said late Monday that the FDA cleared its HIV drug Viread for chronic hepatitis B in adults. The approval was expected -- the drug outperformed the company's Hepsera, the leading HBV treatment, in clinical trials and is expected to take over its market share.

Gilead shares were up 67 cents, or 1.2%, to $57.10.

In more regulatory news, Pain Therapeutics ( PTIE) and King Pharma ( KG) said Tuesday that the Food and Drug Administration granted priority review to Remoxy, an investigational, controlled-release version of pain drug oxycodone that is designed to be abuse resistant. The FDA grants the speedy review to drugs that could potentially offer a significant improvement to currently marketed products. The agency's goal for completing a priority review drug is six months from the date the application was submitted, in this case June 10.

Pain Therapeutics shares were up 71 cents, or 8.4%, at $9.14, while King's added 14 cents, or 1.3%, to $11.29.

On the clinical side, Altus ( ALTU) gave up $2.44, or 49.39%, to $2.50 after the company announced top-line results from a late-stage trial on its Trizytek in patients with cystic fibrosis. The trial met its goal, but results fell short of Street expectations.

In postclose earnings Monday, Medivation ( MDVN) reported a net loss of $18.5 million, or 64 cents a share, widened from a loss of $7.2 million, or 26 cents a share a year prior. Analysts surveyed by Thomson Reuters had predicted a loss of 54 cents a share from Medivation, which recorded no revenue during the quarter. The company also said that it now expects operating expenses in 2008 in the range of $65 million to $75 million, up from prior guidance of between $55 million and $65 million.

Medivation's shares gave up $2.47, or 10.6%, to $22.11.

Omrix ( OMRI) beat consensus targets with its quarterly figures. The company said Monday after the close that it earned $3 million, or 17 cents a share, vs. 9 cents a share a year prior. Revenue increased 71% to $19.2 million, while analysts surveyed by Thomson Financial had predicted 13 cents a share on $17.3 million. Its shares were up 99 cents or 5.3%, at $19.64.

Elsewhere, analysts made a few adjustments to Cardiome ( CRME) a day after the company announced that the Food and Drug Administration requested more safety data on its irregular heart rhythm drug Kynapid. Lehman Brothers cut its price target to $8 from $10 while RBC Capital Markets also reduced its price target by $2 to $11.50.

After taking a hefty cut on Monday, Cardiome shares edged down another 43 cents, or 3%, to $9.35.

Cardiome, Omrix, Altus, Pain Therapeutics and Gilead are all components of the Nasdaq Biotechnology Index, which was down 0.83, or 0.1%, at 917.37.