BioMarin Pharmaceutical Inc. filed a registration statement with the Securities and Exchange Commission to sell 6 million shares of common stock in a public offering.

BioMarin¿s stock opened Monday at $12.19. At that price the offering would raise about $73 million. The stock (NASDAQ:BMRN) fell 59 cents Monday to close at $11.60.

BioMarin said it would use the net proceeds from the sale for the development and commercialization of its lead product candidate, Aldurazyme, which is for the treatment of MPS I; additional clinical trials of and manufacturing of Neutralese for the reversal of heparin anticoagulation; preclinical studies and clinical trials for its other product candidates; potential licenses and other acquisitions of complementary technologies and products; and working capital.

Earlier this month BioMarin and Genzyme General, of Cambridge, Mass., said they plan to file regulatory applications early next year in the U.S., Canada and Europe for Aldurazyme, an enzyme replacement therapy for people with mucopolysaccharidosis I (MPS I). They said preliminary data from a 45-patient, randomized, double-blind, placebo-controlled Phase III pivotal trial were positive.

BioMarin granted the underwriters of the offering an option to buy up to 900,000 additional shares to cover overallotments. Managing underwriters are UBS Warburg LLC, CIBC World Markets Corp. and U.S. Bancorp Piper Jaffray.

As of Sept. 31, BioMarin had $43.9 million in cash and short-term investments, with about 42 million share outstanding.