Link Between Depo-Provera and Meningioma Brain Tumors Ignored by Pfizer, Plaintiffs Indicate

As Pfizer seeks to dismiss claims brought by women diagnosed with brain tumors from the birth control shot, plaintiffs argue the manufacturer failed to provide adequate Depo-Provera meningioma warnings for years.

In response to a motion for summary judgement filed by Pfizer, seeking to avoid liability in thousands of Depo-Provera lawsuits on federal preemption grounds, plaintiffs maintain that the birth control manufacturer had a duty to update the label with warnings about meningioma brain tumor risks, yet failed to do so.

Depo-Provera is a long-acting hormonal contraceptive administered quarterly, containing the synthetic progestin medroxyprogesterone acetate. It has been used by millions of women over the past three decades, since it has been widely promoted as a safe and convenient alternative to daily birth control pills.

However, following the emergence of several studies linking Depo-Provera to brain tumors, Pfizer now faces more than 1,000 lawsuits alleging women were never warned about the risk of developing intracranial meningiomas after receiving the injections. In addition to those claims already filed, Depo-Provera lawyers estimate another 9,000 claims are currently under investigation.

As the number of Depo-Provera meningioma lawsuits filed throughout the federal court system continued to raise common questions of fact and law, a federal multidistrict litigation (MLD) was established earlier this year in the Northern District of Florida, where U.S. District Judge M. Casey Rodgers is presiding over coordinated discovery and pretrial proceedings.

Early in the litigation, Judge Rodgers directed the parties to prepare a small group of pilot test cases for trial dates, which are intended to help gauge how juries may respond to certain evidence and testimony that will be repeated throughout the litigation. 

However, before the evidence is presented in open court, plaintiffs must overcome a series of anticipated pretrial motions seeking to have the litigation thrown out.

Depo-Provera Lawsuit Preemption Arguments

A key battleground in the Depo-Provera litigation is whether the claims can even move forward, with Pfizer relying on a legal doctrine known as federal preemption to try to shut the cases down. Under preemption rules, when state and federal law conflict, federal law controls. 

Drug and medical device manufacturers often invoke this defense in failure-to-warn cases, arguing that FDA regulations prevented them from unilaterally changing their product labels, leaving them in a Catch-22 when accused of not providing adequate warnings, which the currently filed lawsuits claim. 

Late last month, Pfizer filed a motion for summary judgment, suggesting that state law-based failure to warn claims are preempted by federal law, indicating that the company attempted to have the risk of brain tumors added to the warning label in 2023, which was rejected by the U.S. Food and Drug Administration (FDA).

That request followed a February 2023 epidemiological study involving 25 women who developed intracranial meningiomas following Depo-Provera injections. In June of that year, a second study emerged with similar findings, and Pfizer indicates that its own scientists decided the evidence met the threshold for a label warning.

The company argues that since its requests to strengthen the label warnings were rejected, it cannot be held responsible for failure to warn claims.

On September 19, plaintiffs filed a memorandum in opposition (PDF) to the motion for summary judgment, arguing that Depo-Provera was on the market for decades after science had established that the injections could promote brain tumor growth, and only sought to improve the labels after an investigation by foreign regulators.

“First, for decades, Pfizer failed to study meningioma risk, despite mounting evidence and the obligation to update warnings. When it finally did so, Pfizer conducted an incomplete literature search and buried its analysis linking risk level to dosage.”

– Plaintiffs’ Memorandum in Support of Opposition to Pfizer Motion for Summary Judgment

The memorandum states that when Pfizer submitted its request for label changes to the FDA, it did so in a way that still concealed crucial information and peer-reviewed studies about Depo-Provera’s link to meningiomas. Plaintiffs argue that the FDA never got a chance to reject an adequate warning proposal, “because Pfizer never offered one.”

They claim that the information Pfizer provided to the FDA was intentionally broad, implicating an entire class of drugs in the brain tumor risks, including both low-dose oral tablets to high-dose injections. Plaintiffs argue that science did not support this warning, yet did support a more focused concern on Depo-Provera, which Pfizer failed to present to the FDA.

Judge Rodgers has scheduled oral arguments over the dispute for September 29, 2025, after which she will decide whether the litigation can continue to move forward.

Depo-Provera “Pilot” Bellwether Trials

If the litigation survives preemption challenges, Judge Rodgers will move forward with the preparation of the five “pilot” cases to serve as early bellwether trials, which will allow the parties to gauge how juries are likely to respond to certain evidence and testimony that will be repeated throughout the claims.

Although the outcomes of those trials will not be binding on other claims, they are expected to provide critical insight into how juries respond to key arguments and testimony, potentially paving the way for broader Depo-Provera settlement negotiations.

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