GlaxoSmithKline (GSK) and the Food and Drug Administration (FDA) notified physicians yesterday that PAXIL and PAXIL CR (paroxetine HCI) may be linked to a higher rate of birth defects than currently found with similar drugs.
GSK recently conducted a retrospective study of congenital malformations in babies born to 3,581 women taking antidepressants during the first trimester of pregnancy. Preliminary results suggested an increase in the risks of congenital malformations associated with the use of PAXIL as compared to other antidepressants. The malformations were usually cardiovascular, with the most common being ventricular septal defects.
In a letter to healthcare professionals, GlaxoSmithKline noted that the retrospective study was designed to evaluate the relative risk of congenital defects in infants born to women who were taking antidepressants. The study did not include a comparison to infants who were not exposed to antidepressants.
The British drug maker noted that a number of previous studies relating to first trimester exposure to antidepressants have been done since the late 90’s, with various conclusions. The mixed results make it difficult to definitively conclude that paroxetine has a causal relationship to any particular congenital abnormality.
PAXIL currently carries a Category C pregnancy precaution on its label. The precaution indicates that that no well-controlled human studies have been done on the effect of taking paroxetine during pregnancy. Information concerning the new study will be added to the label.
GSK cautioned doctors to “carefully weigh the potential risks and benefits of using paroxetine therapy in women during pregnancy.” They encouraged doctors to discuss the latest findings with their patients.