Paxil Birth Defects

GlaxoSmithKline Pays More Than $1 Billion for Paxil Cases

An article by Bloomberg from 2010 reported that pharmaceutical giant GlaxoSmithKline had paid more than $1 billion to resolve approximately 800 cases alleging its Paxil antidepressant caused birth defects in the children whose mother ingested the drug during pregnancy. The approximate payout for each case was around $1 million dollars. The most common birth defects are cardiovascular defects such as atrial septal defects, ventricular septal defects, hypoplastic left heart syndrome and tetralogy of fallot. These defects are commonly referred to as “holes in the heart.”In some cases, the injuries were so severe that the children underwent heart transplants. Additional defects included craniosynostosis, club foot and persistent pulmonary hypertension of the newborn (PPHN).

Paxil, also known generically as Paroxetine, was approved in 1992 and generated $793 million in sales in 2009, which was approximately 1.8 percent of Glaxo’s total revenue. Paxil is part of a drug class known as “selective serotonin reuptake inhibitors” or “SSRIs.” These drugs are used to treat depression and anxiety disorders. In an effort to widen the market, GlaxoSmithKline began marketing the drug to women of childbearing age. During this timeframe, there was evidence that Paxil caused birth defects in animal studies conducted by GlaxoSmithKline.

In 1998, a study published by Kulin, et al. entitled “Pregnancy Outcome Following Maternal Use of the New Selective Serotonin Reuptake Inhibitors: A Prospective Controlled Multi-Center Study in the Journal of the American Medical Assocaition” found that there were malformations associated with the use of Paxil during pregnancy.

In September of 2005, GSK sent a “Dear Healthcare Professional” letter advising the medical community that preliminary results of a recently conducted retrospective epidemiologic study suggest an increase in the risk of congenital malformations, mostly cardiovascular, associated with the use of Paxil in the first trimester of pregnancy. More specifically, the letter provided that the preliminary analysis of the data yielded adjusted odds ratios of 2.20 (95% Confidence interval [CI]: 1.34-3.63) for congenital malformations as a whole, and 2.08 (CI: 1.03-4.23) for cardiovascular malformations alone, for Paxil as compared to other antidepressants.

On December 8, 2005, the FDA issued a news release advising that early results of new studies suggest that Paxil increases the risk for birth defects, particularly heart defects, when taken during the first three months of pregnancy. Consequently, the label for Paxil was changed from pregnancy category C to D. The current Paxil label carries the FDA pregnancy Category D warning which means there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but the potential benefits from the use of the drug in pregnant women may be acceptable despite its potential risks.