Washington Editor

Genzyme General and its partner, BioMarin Pharmaceutical Inc., said the FDA accepted the biologics license application for Aldurazyme and granted it six-month priority review status.

Aldurazyme is an investigational enzyme replacement therapy for patients with mucopolysaccharidosis 1 (MPS 1), a fatal genetic disease for which no specific treatments exist. Roughly 3,000 to 4,000 people worldwide suffer from the disease, spokesmen from both companies told BioWorld Today.

Stock prices for the companies were on the rise Monday, with BioMarin's (NASDAQ:BMRN) closing at $4.92, up 61 cents, or 14.2 percent, and Genzyme's (NASDAQ:GENZ) at $19.95, up $1.55, or 8.4 percent. The Genzyme gain came despite its revised financial guidance also released Monday showing reduced revenue expectations for Renagel, a kidney dialysis drug.

Genzyme, of Cambridge, Mass., has reduced this year's revenue guidance from $1.1 billion to $1.15 billion, down to $1.05 billion to $1.1 billion. Renagel sales for the year are now expected to be between $155 million and $165 million, compared to the previous guidance of $200 million to $210 million, according to a statement released by the company. In 2001, worldwide Renagel sales totaled $177 million.

Bill Tanner, managing director of Leerink Swann & Co. in Boston, told BioWorld Today that the demand for Renagel likely has slowed because the drug is expensive and there are alternative products on the market. For example, he said some patients use Phoslo, from Braintree Labs, or the antacid Tums to achieve the same results as Renagel.

Nevertheless, the orphan drug Aldurazyme fits nicely into the Genzyme business model because it's an enzyme replacement therapy like Cerezyme, the company's product for Gaucher's disease, and Fabrazyme, for Fabry's disease. (An FDA advisory panel will consider the application for Fabrazyme on Sept. 26. It is approved in Europe.)

Tanner said if Aldurazyme makes it to market, it could end up producing a tidy profit for Genzyme. "They are charging about $165,000 per patient per year for Cerezyme and you really don't know how many patients there are per year for Aldurazyme. But you can envision this generating, if approved, several hundred million long term," he said.

Bearing in mind, per a 1998 joint venture with BioMarin, of Novato, Calif., profits related to Aldurazyme have to be split 50-50. Under the agreement, BioMarin is responsible for manufacturing the drug and Genzyme will take on commercialization and marketing roles. Genzyme has about 10 years of experience selling enzyme replacement therapies, Bo Piela, a spokesman for Genzyme, told BioWorld Today. (See BioWorld Today, Sept. 16, 1998.)

The companies filed the final portions of the rolling biologics license application in late July. The BLA includes clinical data from the six-month placebo-controlled Phase III trial of Aldurazyme, six months of data from the ongoing open-label Phase III extension study and three years of data from the Phase I trial and extension study. (See BioWorld Today, July 30, 2002; June 25, 2002; and April 16, 2002.)

Joshua Grass, BioMarin's manager of investor and financial relations, told BioWorld Today that the FDA's acceptance of the Aldurazyme application is an important step for the company. "We are looking forward to working with Genzyme and the FDA to get this to patients as quickly as possible."

MPS 1 is a progressive, debilitating and fatal genetic disease caused by a deficiency of the enzyme alpha-L-iduronidase. That deficiency leads to the accumulation of complex carbohydrates in the lysosomes of cells, leading to the progressive dysfunction of cellular, tissue and organ systems, the companies said.

In accordance with guidelines set under the Prescription Drug User Fee Act, the FDA has six months beginning July 29, 2002, the date on which the BLA was filed, to respond to BioMarin and Genzyme on the Aldurazyme application.

The companies expect a response on the European application late this year or early next year.