NeutroSpec Lawyers

MONDAY, Dec. 19 (HealthDay News) -- Acting at the request of the FDA, the makers of NeutroSpec, an imaging agent approved to diagnose appendicitis, are voluntarily withdrawing the product from the market.

The action came after reports of two deaths and 20 "serious and life-threatening" adverse events linked to use of NeutroSpec, the agency said.

The serious adverse events included cardiopulmonary failure, central nervous system reactions, and infusion reactions. Some of the patients had to be admitted to intensive care, Dr. Sandra Kweder, deputy director of the Office of New Drugs at the FDA's Center for Drug Evaluation and Research, said at a news conference Monday.

In addition, there were 46 other patients who had similar but less severe reactions. Most of the patients ranged in age from 45 to 80 and older, although one was a teenager.

"The company made the decision to suspend marketing based on the events being life-threatening and the availability of other means to diagnose appendicitis that don't carry these risks," Kweder said. "They are urging health-care providers to stop using existing stocks, and to contact the company regarding their return."

The reactions occurred within minutes of the drug's administration by injection.

"Most of the patients, but not all of them, did have some sort of underlying cardiac or lung condition that might somehow have placed them at high risk for an event but they may not have been ill at that time," Kweder said. "We don't know the specific way that NeutroSpec and these adverse events is related, but the consistent characteristics of events in the patients makes it likely they were due to NeutroSpec.

NeutroSpec (Technetium 99m Tc Fanolesomab) is a murine or mouse monoclonal antibody tagged with Technetium, a radioactive molecule that allows it to be seen on an imaging scan. The product is made by Palatin Technologies Inc. and marketed by Mallinckrodt.

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