The FDA has approved Zofran for two purposes: prevention of chemotherapy and radiation- induced nausea and vomiting, and prevention of postoperative nausea and vomiting. Despite having been on the market (being first approved for intravenous use and shortly thereafter for injections, and still later, in pill form) since 1991, the labeling information as it relates to pregnancy has not changed in any meaningful way in the ensuing 24 years.
As it relates to pregnancy, the Zofran label explains that studies in pregnant rats and rabbits did not show evidence of impaired fertility or harm to the fetus. It goes on to say that “[T]here are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used in pregnancy only if clearly needed.”
This labeling language as to pregnancy has not changed in any material way throughout all the years that Zofran has been available in pill form. This is true despite the fact that the makers of Zofran were well-aware that this drug was being widely prescribed to pregnant women regardless of whether they were having morning sickness symptoms—or even if they did, whether the symptoms were mild, moderate, or severe. The maker of Zofran also has settled a civil lawsuit that contained allegations that it actively promoted the use of Zofran in pregnancy. If true, this would be a clear violation of FDA regulations.
The FDA has five categories to indicate the potential of a drug to cause birth defects if used during pregnancy. When it first came on the market, Zofran was classified in category B, which means that animal studies (rats and rabbits, for example) did not show a risk to the fetus and “there are no adequate and well-controlled studies in pregnant women.”
The bottom line seems to be that the maker of Zofran is claiming that, despite all the data available to it after nearly a quarter century, nothing has changed, and they have no responsible reason to change the label.
The FDA does have a Pregnancy Category X, and it says this: “Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in use of the drug in pregnant women clearly outweigh potential benefits.”
From all the years of adverse reports about Zofran and birth defects, doesn’t this sound like the right thing for the maker of Zofran to have published about an off-label use of its drug that it knew was occurring for thousands of expectant mothers every day?