Shares of

Align Technology

(ALGN) - Get Report

were among the best-performing health-related stocks Wednesday, rising 21% after the company posted first-quarter earnings and sales above expectations.

The maker of teeth-straightening products posted earnings of $1.9 million, or 3 cents a share, on sales of $51.2 million. Analysts surveyed by Thomson First Call were expecting break-even earnings on sales of $46.9 million. A year ago the company posted pro forma earnings of $2.8 million, or 4 cents a share, on sales of $39.2 million. Shares were trading up $1.45 to $8.40.

Senomyx

(SNMX)

rose 8% after the company announced a three-year extension to its discovery and development agreement with

Nestle

. Under the extension, Nestle will pay the company incremental discovery and development funding of up to $6.6 million. Upon commercialization of products containing flavors and flavor enhancers, Senomyx will receive royalty payments tied to sales targets. The new agreement between the two companies relates to the discovery and commercialization of flavors and flavor enhancers in the dehydrated and culinary food and frozen food segments. Shares of Senomyx were trading up 88 cents to $11.45.

Shares of

St. Jude Medical

(STJ)

rose 10% after the medical device maker posted first-quarter earnings and sales that topped expectations and said that second-quarter earnings would beat expectations as well. Excluding research and development expenses related to an acquisition, the company earned $131.8 million, or 35 cents a share, on sales of $663.9 million. Analysts were expecting earnings of 33 cents a share on sales of $646.5 million. A year ago the company earned $95.2 million, or 26 cents a share, on sales of $548.6 million. Looking ahead, St. Jude forecast second-quarter earnings of 35 cents to 37 cents a share, ahead of the 34 cents that analysts had been expecting. Shares were trading up $3.47 to $39.73.

Medicines Co.

(MDCO) - Get Report

fell 2% after the drug developer posted first-quarter earnings and sales that fell short of expectations. The company earned $2.3 million, or 5 cents a share, on sales of $43.6 million. Analysts were expecting earnings of 6 cents a share on sales of $44.5 million. A year ago the company earned $4.2 million, or 8 cents a share, on sales of $31.3 million. Shares were trading down 47 cents to $22.03.

Shares of

Ariad Pharmaceuticals

(ARIA)

rose 6% after the company's mTOR inhibitor, AP23573, received fast-track status from the Food and Drug Administration. The drug developer said the FDA's decision was based in part on both phase I and phase II clinical trials conducted in refractory sarcoma patients. Based on the FDA news, the company said that it would pursue treatment of soft-tissue and bone sarcomas as its initial registration path for its bone cancer drug. Shares were trading up 36 cents to $6.36.

Other health care volume movers included

Pfizer

(PFE) - Get Report

, down 73 cents to $26.69;

Amgen

(AMGN) - Get Report

, down 82 cents to $57.76;

Eli Lilly

(LLY) - Get Report

, down 90 cents to $58.55;

Merck

(MRK) - Get Report

, down 42 cents to $34.26;

Johnson & Johnson

(JNJ) - Get Report

, down $1.01 to $68.04;

Elan

(ELN)

, down 4 cents to $4.01;

Bristol-Myers Squibb

(BMY) - Get Report

, down 7 cents to $25.56; and

Schering-Plough

( SGP), down 21 cents to $20.02.