The US Food and Drug Administration (FDA) has approved a label change to Pfizer’s injectable contraceptive, Depo-Provera (medroxyprogesterone acetate), which will warn users of their increased risk of meningioma.

The FDA’s crackdown on Depo-Provera comes amid a highly publicised legal battle between Pfizer and more than 2,000 women, who are currently suing the New York-based pharma after they developed meningiomas they believe are caused by exposure to the contraceptive.

Depo-Provera contains progestin, a synthetic form of the sex hormone progesterone. While it has been on the contraceptive market since the early 1990s, a recent study published in the British Medical Journal has uncovered the heightened risk of intracranial meningioma associated with the jab’s prolonged use.

A December 2023 National Health Statistics Report estimates that nearly 24.5% of all sexually experienced women in the US have used Depo-Provera at some point between 2015 and 2019.

Meningiomas are tumours that grow in the protective membranes that coat the brain and spinal cord. Patients with meningiomas commonly experience headaches, seizures, weakness and numbness. Though they are typically benign, they can have a significant impact on a patient’s quality of life (QoL). In some cases, they are also life-threatening.

The FDA’s call to enforce a label warning for Depo-Provera marks a potential turn in the agency’s stance on the contraceptive, as it previously rejected Pfizer’s label update application in 2024.

FDA clampdown could spell legal trouble for Pfizer

Throughout the legal battle between Pfizer and the 2,000-plus plaintiffs, claims against the big pharma have largely centred around its failure to warn doctors and patients of the risk of meningioma associated with Depo-Provera’s use.

Pfizer has previously argued in court that the FDA had prohibited it from including a label warning on Depo-Provera, thus prompting the company to request the dismissal of such lawsuits.

However, Ben Martin, founder of the drug and medical device litigation group, Ben Martin Law Group, told Pharmaceutical Technology that this defence may no longer hold up in court.

Martin said: “This ‘impossibility’ pre-emption argument should now fail given that a warning was not only possible but that the FDA is now requiring such a warning.

“Pfizer has known for decades that there may be an association between the use of Depo-Provera and the development of meningiomas.”

In his eyes, the New York-based pharma “could and should have performed studies exploring this link”, which would have uncovered the greater risk of developing meningioma with the use of Depo-Provera versus not using it.

Bryan Aylstock  of  Aylstock Witkin Kreis & Overholtz, Christopher Seeger of Seeger Weiss, and Ellen Relkin of Weitz & Luxenberg, co-lead counsel in the Depo-Provera Products Liability Litigation echoed this sentiment, adding that Pfizer’s misconduct has caused “lasting neurological damage, vision loss and death” in women who developed brain tumours caused by Depo-Provera.

“We applaud the FDA in finally requiring this label change to better inform and protect women,” they concluded.