Federal health officials cautioned women Friday that use of a GlaxoSmithKline drug during the first three months of pregnancy shows possible links to birth defects.
Newly reported data suggest a connection between the drug Lamictal, used to treat bipolar disorder and epilepsy, and lip defects in infants, according to a safety alert posted on the Food and Drug Administration's Web site.
In a registry of 564 pregnant women who took the drug during the first trimester, five gave birth to babies with a cleft lip or cleft palate, which is a gap in the upper lip or roof of the mouth. The agency advises women taking Lamictal who are pregnant or thinking of becoming pregnant to speak with their doctor.
While FDA says more data are needed before verifying the connection, it notes that similar registries have not recorded such a high occurrence of the defect.
GlaxoSmithKline said it first learned of the registry's findings in December 2005 and immediately notified the FDA. In June this year the British drug maker sent a letter explaining the findings to doctors.
"What the North American registry found hasn't been replicated by other pregnancy registries," said Holly Russell, GlaxoSmithKline's director of product communications. "It's FDA's position as well as our own that without confirming data the important thing is to continue to monitor data from ongoing pregnancy registries and other sources."
GlaxoSmithKline's revenues for Lamictal in fiscal 2005 were $1.34 million.
The drug maker announced last week that FDA approved Lamictal for an additional prescribed use in epilepsy patients who suffer "grand mal" seizures. The drug was previously approved to treat four other types of epileptic seizures, as well as adults with bipolar I disorder.
Shares of GlaxoSmithKline plc fell 2 cents Friday to $53.53 in midday trading on the New York Stock Exchange.
