Biopure Corp. said the FDA completed its review of the company's biologic license application for the blood substitute Hemopure and has asked for additional information but not additional trials, boosting the company's stock more than 20 percent.

The FDA's letter, Cambridge, Mass.-based Biopure said, "focuses primarily on clarification of clinical and preclinical data and includes some comments on labeling." While that requires a complete response from Biopure, the avoidance of additional trials caused investors to bid up Biopure shares. Its stock (NASDAQ:BPUR) rose $1.33 Friday, or 22.3 percent, to close at $7.30.

In a prepared statement, the company said it would "work with the agency to address the remaining questions and will provide our answers as expeditiously as possible."

The company has applied for approval of the product in acutely anemic adult patients undergoing orthopedic surgery and for the elimination or reduction of red blood cell transfusions in the patients. Thirty days remain on the FDA's clock for a verdict on the product, although the countdown now has been suspended until Biopure submits a complete response.

Hemopure is designed to be a blood substitute and is made of hemoglobin extracted from bovine red blood cells. The cells are purified, chemically crosslinked and then formulated in 250 milliliters of a salt solution. The biologics license application for the product was filed in the summer of 2002 and accepted for review on Oct. 1. The company does not have a marketing partner for the product, although it is approved for sale in South Africa. (See BioWorld Today, Aug. 2, 2002.)

The company raised $17.2 million near the end of July. It reported $15.1 million in cash and investments as of April 30. (See BioWorld Today, July 25, 2003.)