A few health stocks regained footing Tuesday, with some moving on analyst notes, deals and product news. Of those on the rebound, NPS Pharmaceuticals ( NPSP) ended a collaboration dating back to 2001 with AstraZeneca ( AZN) that was focused on developing central nervous system disorder treatments. NPS will receive $30 million for its assets related to the collaboration and will use the proceeds for the development of its late-stage pipeline. NPS shares, which gave up more than 13% Monday on news that George Soros scaled back his stake in the company, climbed back up Tuesday on the latest news, rising 59 cents, or 12%, to $5.34. The stock is a component of the Nasdaq biotechnology index, which was up 5.07, or 0.6%, to 885.41. AstraZeneca was down just 48 cents, or 0.9%, to $51.79. Also reclaiming ground, Acusphere ( ACUS) issued a statement after Monday's close regarding potential Food and Drug Administration action related to approved and commercially available ultrasound contrast agents. The company assured investors that its experimental imaging agent is structurally different from those under scrutiny. The stock gained 18 cents, or 14%, to $1.54. Brean Murray Carrat analyst Jonathan Ashcoff upgraded Spectrum Pharmaceuticals ( SPPI) to buy from hold, expecting ozarelix for benign prostatic hyperplasia to demonstrate positive safety and efficacy results in a phase IIb trial and predicting the company will initiate late-stage studies by the end of 2007. Aschoff said in the report that he also expects approval of ISO-Vorin for bone cancer and the filing of a supplemental new-drug application (sNDA) for the drug in colorectal cancer both in the first half of 2008. Shares rose 23 cents, or 5.5%, to $4.39.