With plans to submit a new drug application this quarter, Prestwick Pharmaceuticals Inc. filed for an initial public offering to raise an estimated $74.8 million in preparation for the potential launch of its dopamine depletor, tetrabenazine.

The Washington-based company has not specified the number of shares or share price for the offering, but reported in its prospectus that proceeds would be used to fund the anticipated U.S. launch of tetrabenazine for the treatment of chorea associated with Huntington's disease. The company, which is seeking a listing on Nasdaq under the symbol "PWCK," could not be reached for comment.

UBS Investment Bank, CIBC World Markets and Deutsche Bank Securities, all of New York, are serving as underwriters.

Prestwick said it received fast-track designation for tetrabenazine, and if the NDA is filed this quarter, the company would be eligible for FDA approval as early as the first quarter of 2006. The company licensed rights to develop and commercialize tetrabenazine, a selective and reversible dopamine depletor, from UK-based Cambridge Laboratories Ltd. The product is marketed by Prestwick in Canada under the brand name Nitoman and by Cambridge Laboratories in Europe under the brand Xenazine.

Since there are no existing approved treatments in the U.S. for chorea, described as hyperkinetic movement disorders caused by an excess of dopamine in the basal ganglia, tetrabenazine also was granted orphan drug status by the FDA.

The company also received orphan status for tetrabenazine in a second movement disorder, tardive dyskinesia, and is planning a Phase III trial in that indication. The product is being considered as a treatment for Tourette's syndrome, as well.

In addition to its tetrabenazine program, Prestwick said it intends to use proceeds from the offering to in-license potential product candidates and for general corporate purposes, including the ongoing development of other products in its pipeline, such as Lisuride, a dopamine agonist. The company said it plans to seek orphan drug and fast-track designation for that product, as well.

The opposite of tetrabenazine, Lisuride is intended to stimulate the production of dopamine in patients with Parkinson's disease who experience a loss of motor control caused by the degeneration of nerve cells in the brain. The product already is marketed in Europe in an oral formulation, but Prestwick said a subcutaneous infusion might provide a longer half-life and a more steady level of absorption. The company's Lisuride Subcutaneous, an external pump that infuses the drug under the skin, and Lisuride Transdermal, designed as a weekly patch, both are intended to deliver continuous levels of dopaminergic stimulation.

Prestwick licensed Lisuride from Berlin-based NeuroBiotec GmbH, which has conducted European trials. With those data in hand, Prestwick could file an investigational new drug application during the second half of this year and possibly begin with Phase III trials in early 2006.

The company also plans to file an IND this year for its schizophrenia drug, D-Serine, a selective amino acid co-agonist. A Phase IIb trial is anticipated to begin next year. Prestwick plans to release results from a Phase II trial of its sleep apnea drug, PPI-03306, during the fourth quarter of 2006.

The company posted a net loss of about $20 million for 2004 and ended the year with about $30.9 million in cash and cash equivalents due to a private financing round completed in early December. A Series B round raised about $37 million. (See BioWorld Today, Dec. 7, 2004.)

Principal stockholders of Prestwick include San Francisco-based Sofinnova Ventures and Palo Alto, Calif.-based Vivo Ventures, which own 19.7 percent each, or 12.2 million shares apiece. Waltham, Mass.-based Atlas Ventures owns 17.3 percent, or 10.7 million shares, and Westport, Conn.-based Pequot Capital Management Inc. owns 12.9 percent, or 8.2 million shares.