Updated from 1:59 p.m. EDT

Nanogen

(NGEN)

was among the drug and biotech stocks seeing action Friday, rising after the company said it received a U.S. patent for technology that detects genetic variants utilizing base stacking.

The patent is a continuation of patents issued to Nanogen that cover methods and apparatus that are useful for detecting genetic variants. The patent covers the application of base-stacking technologies that both capture and probe oligonucleotides to bind and discriminate nucleic acid sequences, the company said. The most recent patent brings Nanogen's intellectual property portfolio to 59 patents. Shares of Nanogen traded up 52 cents, or 8.3%, to $6.80.

Shares of

ATS Medical

(ATSI)

slumped after the company announced the sale of about $13.1 million in stock. The company sold about 3.7 million shares at $3.55 apiece. ATS did not issue any warrants in connection with the offering. Shares of ATS Medical traded down 58 cents, or 12.7%, to $4.

Crucell

( CRXL) rose after the biotech company announced the discovery of an antibody that protects against the SARS virus infection. The study results, which will be published in the June 26 edition of the Lancet medical journal, will show that a human monoclonal antibody protects ferrets from SARS. The company hopes the results may eventually lead to the development of an antibody for use in humans. Shares of Crucell traded up 41 cents, or 5%, to $8.64.

Other health care volume movers included

Pfizer

(PFE) - Get Report

, down 99 cents to $33.82;

Schering-Plough

( SGP), down 52 cents to $18.18;

Amgen

(AMGN) - Get Report

, down 39 cents to $54.13; and

Genentech

( DNA), down 53 cents to $54.50.