Encysive Pharmaceuticals was moving higher after one of its units closed a private placement of $60 million of nonconvertible, nonrecourse promissory notes to institutional investors. The notes are secured by royalties to be paid from sales of Argatroban, a drug licensed by Encysive to GlaxoSmithKline ( GSK - Get Report). Encysive was adding 17 cents, or 5%, to $3.59.

BioCryst Pharmaceuticals ( BCRX - Get Report) was rising nearly 3% after posting a smaller-than-expected fourth-quarter loss. BioCryst, which manufactures vaccines for the bird flu, was rising 31 cents to $10.85.

Shares of MedImmune were falling 9.1% as the company reported weaker-than-expected fourth-quarter sales. MedImmune was recently losing $3.11 to $30.90.

Forest Laboratories ( FRX) was slipping after the company terminated the development of a pneumonia treatment with another firm. Shares were off $2.36, or 4.1%, to $55.48.

Among health care stocks gaining ground, Allos Therapeutics was jumping 6.4% to $8.31, Nektar Therapeutics ( NKTR - Get Report) was gaining 3.3% at $12.29, and Millennium Pharmaceuticals was higher by 3.1% to $11.44.

As for the losers, Adams Respiratory Therapeutics slumped 7% to $42.13, Genomic Health ( GHDX) was losing 7% to $19.98, and Merck ( MRK - Get Report) was off 1.1% to $44.15.