Zofran Lawsuit: How the Birth-Defect Case Ended (2026)

What Families Claimed Against GSK

Families argued that Zofran taken early in pregnancy harmed their babies. According to the federal court's June 2021 summary judgment order, most plaintiffs were women who used the drug while pregnant and their children, who had mainly orofacial defects and cardiac ventricular or septal defects. Their core claim was failure to warn – GSK never gave an adequate warning about these risks.

The same order notes the FDA first approved Zofran in 1991 to prevent nausea and vomiting from chemotherapy, radiation, and surgery. It was never approved for morning sickness. Even so, doctors prescribed it off-label to pregnant women for years – meaning they used it for a purpose the FDA had not cleared.

GSK's own 2021 annual report filed with the SEC summarized the charges. Plaintiffs said the company sold Zofran knowing it was unsafe during pregnancy, failed to warn of the risks, and illegally pushed off-label use in pregnant women.

How the Cases Were Consolidated

Lawsuits began landing in federal courts across the country in 2015. On October 13, 2015, the Judicial Panel on Multidistrict Litigation grouped them into a single proceeding in Massachusetts. The next day, Judge Saylor issued MDL Order No. 1, which coordinated all transferred and future cases for pretrial work.

An MDL, or multidistrict litigation, is not a class action. Each family keeps its own lawsuit, but one judge handles shared steps like evidence gathering and expert rulings. By 2021, GSK reported it faced over 400 product liability cases in the Zofran MDL, according to its SEC filing.

What the Research Showed

The science never settled in the plaintiffs' favor. A large Danish study of 608,385 pregnancies, published in the New England Journal of Medicine in 2013, found no significantly higher risk of major birth defects, stillbirth, or miscarriage among women who took ondansetron, the generic name for Zofran.

A later JAMA study of U.S. Medicaid pregnancies from 2018 found first-trimester use was not tied to heart malformations or overall birth defects. It did report a small increased risk of oral clefts. That mixed picture made it hard for families to prove the drug caused their children's injuries.

The FDA's Repeated Decisions on a Pregnancy Warning

The FDA reviewed Zofran's pregnancy safety several times, and each time it declined to add the warning plaintiffs wanted. The court's 2021 ruling laid out that history in detail:

In 2010, the agency asked GSK for more pregnancy safety data but required no label changes. It denied a 2013 citizen petition seeking a fetal risk warning on October 27, 2015. That same year, Novartis – which bought the rights to Zofran from GSK in 2015 – proposed a warning against use in pregnancy, and the FDA rejected it.

GSK filed its own citizen petition on November 1, 2019, and the FDA denied it on January 15, 2021. On April 29, 2021, the agency approved an updated label stating that studies on ondansetron and major birth defects had reported inconsistent findings with important methodological limitations.

How the Litigation Ended

The case turned on a legal doctrine called federal preemption. In plain terms, when federal rules make it impossible for a drug maker to change a label, state-law claims for failing to warn usually cannot go forward.

The Preemption Ruling

Judge Saylor first denied GSK's preemption motion on February 5, 2019, finding disputed facts that a jury would need to weigh. Later that year, the U.S. Supreme Court held in Merck Sharp & Dohme Corp. v. Albrecht that preemption is a legal question for judges, not juries.

GSK renewed its motion. On June 1, 2021, Judge Saylor granted it, concluding the FDA had been fully informed and would not have approved the pregnancy warning plaintiffs said state law required. The company reported that the court entered judgment for GSK in every pending MDL case and closed the proceeding. The same filing notes GSK was also defending two state court cases and four proposed class actions in Canada.

The Appeal and Court Costs

Plaintiffs appealed on July 1, 2021. On January 9, 2023, a First Circuit federal appeals panel upheld the dismissal. It found that certain Japanese animal studies were not new safety information and that the FDA's 2021 label approval clearly rejected the warning plaintiffs sought.

One more blow followed. On February 28, 2024, Judge Saylor taxed $453,989.18 in costs against the plaintiffs, with case-specific costs such as medical records assigned to individual cases and the rest split equally.

GSK's 2012 Federal Fraud Settlement

Before the injury lawsuits, GSK faced federal prosecutors over its marketing. On July 2, 2012, the U.S. Attorney's Office in Massachusetts announced that GSK would plead guilty and pay $3 billion – $1 billion in criminal penalties and $2 billion in civil claims.

The deal resolved allegations that GSK marketed Zofran to pregnant women for morning sickness, even though some versions were cleared only for nausea after surgery. Prosecutors described it as the biggest health care fraud resolution the country had ever seen. However, that settlement paid the government, not injured families, and it did not prove Zofran caused birth defects.

Filing Deadlines for Zofran Claims

Every state sets a statute of limitations for injury claims, and many run only a few years. For injuries to children, some states pause the clock until the child becomes an adult, but rules vary widely. With the federal litigation closed and the preemption ruling upheld, new Zofran birth-defect claims typically face serious hurdles.