Skip to Content

FDA Issues Public Health Advisory on use of NeutroSpec

December 19, 2005 -- The Food and Drug Administration (FDA) today issued a Public Health Advisory to alert health care providers that the agency has requested the market withdrawal of the diagnostic imaging agent NeutroSpec [Technetium (99m TC) Fanolesomab] pending further review of reported deaths and serious and life-threatening adverse events associated with use of the product. The manufacturer, Palatin Technologies Inc. and marketing partner, Mallinckrodt, have agreed to implement an immediate voluntary market suspension making the product unavailable for approved or investigational uses.

Postmarketing adverse events that have been reported to the FDA from patients receiving NeutroSpec include shortness of breath and sudden drops in blood pressure which have led to the death from cardiopulmonary failure in two patients and in other patients required cardiopulmonary resuscitation, oxygen and/or intravenous fluids. These events have occurred within minutes following Neutrospec administration. FDA said the decision to suspend marketing was based on the life-threatening nature of the associated adverse events, the unpredictability of the reaction, and availability of other means of diagnosing appendicitis that do not carry these risks.

In pre-market studies submitted to the Agency as part of the drug's application for approval, NeutroSpec was administered to 523 patients. These studies revealed relatively few safety concerns. Most of the adverse events reported since marketing occurred in patients who were given the drug post-approval on an off-label basis. All of the reactions occurred within minutes after NeutroSpec was administered. There is no evidence that patients who already safely received the drug face any long-term risk.

NeutroSpec, approved for marketing in July 2004, is a diagnostic imaging agent that is administered intravenously to help diagnose appendicitis in patients five years and older with possible appendicitis who lack its conventional signs and symptoms. Despite the withdrawal of Neutrospec, there remain several alternative ways to diagnosis appendicitis, including helical CAT scans and ultrasound. These methods are not associated with the adverse events reported with use of NeutroSpec.

FDA urges health care providers to discontinue use of existing stocks of NeutroSpec and to contact Palatin Technologies regarding their return. FDA is conducting further investigation into the deaths and adverse events associated with NeutroSpec. The Agency is working closely with the manufacturers of the product to evaluate the risks and benefits associated with its use.

FDA also plans to convene an advisory committee meeting in early 2006 to discuss the existing data about the risks and benefits of NeutroSpec, what additional safety measures can be taken with its use, and what indications may exist where benefits of the product are outweighed by the known risks. The FDA will notify health care providers and patients in a timely manner following further scientific investigation of adverse event reports.

Source: FDA

Posted: December 2005