Genzyme drug may be on hold longer than expected

The clean-up is underway at Genzyme's Corp.'s manufacturing plant in Allston, after a virus was found in a bioreactor about two weeks ago.

Genzyme Corp. said today that one of two drugs that treat rare genetic disorders may have to be rationed longer than it previously estimated.

The Cambridge biotechnology company said the additional time is needed so vaporized hydrogen peroxide can be dispersed throughout the purification area as well as the cell-culture area at the company's Allston Landing production site. "We've decided to sanitize the entire manufacturing facility, not just the cell-culture production area," said company spokeswoman Lori Gorski.

In addition, the company said, inventory for one of the drugs, Cerezyme, is lower and demand higher than it first calculated after production was halted.

Genzyme previously estimated Cerezyme sales would be put on hold for four weeks, and that sales of the other drug, Fabrazyme would be delayed six to eight weeks. Now, it believes they could both be delayed six to eight weeks. The drugs are enzyme replacement therapies for rare genetic disorders. Cerezyme treats Gaucher disease, while Fabrazyme treats Fabry disease. The conditions cause waste to build up in the body, producing symptom such as swollen organs.

Because of the production shutdown, doses of the drugs will have to be temporarily rationed for about 8,000 patients worldwide. The treatments, administered intravenously about every other week, cost $200,000 a year per patient, on average. The plant, overlooking the Charles River, is scheduled to resume operations by the end of July.

Citing the longer sales interruption, Mark Schoenebaum, senior biotechnology analyst at Deutsche Bank, today boosted his forecast of Genzyme's revenue shortfall stemming from the virus to $245 million, up from $100 million in an earlier forecast. The incident will shave 23 to 49 cents off the company's earnings per share, up from the 17 to 35 cents previously forecast, Schoenebaum estimated.

In its progress report today, Genzyme also said regulatory officials in the United States and Europe have given the company approval to distribute stockpiles of Cerezyme and Fabrazyme in its inventory. Genzyme had to prove to the Food and Drug Administration that the drugs had been thoroughly tested to assure there were no traces of the virus, Vesivirus 2117, found in the plant. While the virus is not considered harmful to humans, it could affect the growth of cells used to make the two drugs.
(By Robert Weisman, Globe staff)