Earnings, analyst actions and a buyout moved a few individual health stocks in both directions on Thursday, but did little for the sector overall.

The Nasdaq and Amex biotech indices slightly underperformed the broader markets, shedding 0.87% and 0.96%, respectively.

One big mover on Tuesday came from Iomai , which is not a component of the indices. A buyout sent shares of the biotech soaring 117% to $6.33. Intercell AG announced late Monday a deal to acquire the company in a stock and cash transaction valuing the biopharmaceutical company at roughly $189 million. Intercell will pay $6.60 a share for Iomi -- a 126% premium to the stock's closing price Monday.

Elsewhere, in medical devices, Abbott Labs ( ABT - Get Report) said that in the Spirit III trial for its Xience V stent -- a mesh tube used to prop open clogged arteries -- proved safer than Boston Scientific's ( BSX - Get Report) Taxus stent at two years. The company said the Xience V stent resulted in a 45% reduction in the risk of major cardiac events and a 32% reduction in the risk of cardiac events related to the treated vessel at two years in comparison to the Taxus device.

The trial, which involved just more than 1,000 patients, is the basis for the Xience V's premarket application for Food and Drug Administration approval. Abbott shares were up $1.47, or 2.8%, at $54.25, while Boston Scientific shares gave up 38 cents, or 2.8%, to $13.03.

Meanwhile, medical device company NxStage ( NXTM) bled $1.86, or 27.6%, to $4.88, on Tuesday.

The company reported a net loss of $13.9 million, or 38 cents a share, widened from a net loss of $12.0 million, or 41 cents a share, for the first quarter of 2007. But, on an adjusted EBITDA basis, the company said it lost of $8.3 million, down from a loss of $10.7 million a year earlier. First quarter revenue totaled $31.0 million, vs. $8.4 million in the year-ago period.

Looking ahead, NxStage said to expect an adjusted net loss of between $28 million and $31 million on revenue in the range of $130 million to $135 million.

Also down, Tercica shares slid 97 cents, or 19.4%, to $4.02, after it released its earnings. The biopharmaceutical company said its first-quarter loss widened to $17.5 million, or 34 cents a share, from $12.4 million, or 25 cents a share in the year-prior period. Revenue increased to $4.6 million from $1.3 million, falling short of the Thomson Reuters estimate of 30 cents a share on revenue of $5.9 million.

Faring better on earnings, biopharmaceutical company Crucell reported a net loss of 9 million euros, or $13.91 million, down from 18.5 million euros in the year-prior period. Results beat the expectations of analysts surveyed by Thomson Reuters who pegged a loss of 14 million euros.

The company reported a 36% hike in sales to 47.9 million euros in the quarter, and maintained its guidance for the full year. Shares were up $1.52, or 8.5%, at $19.45.

Outside of earnings, a few other stocks benefitted from analyst actions. Medarex gained ground a day after releasing its quarterly results as Needham analysts upped their rating for the stock to buy from hold. Shares rose 67 cents, or 9.5%, to $7.70.

Then ImClone ( IMCL), which has been the center of some investor speculation ahead of data to be presented at the American Society of Clinical Oncology (ASCO) conference, saw shares added 88 cents, or 2.1%, to $42.46 on Tuesday. A day after the stock suffered a downgrade, Summer Street Research upgraded the stock to buy from neutral. "At $41.58 heading into ASCO, the risk/reward profile of owning the shares is positive," wrote Summer Street's Carol Werther in a note to investors.