Xeljanz Lawsuit: The Heart and Cancer Warning Claims

The FDA Warnings

Xeljanz (tofacitinib), made by Pfizer, is a JAK-inhibitor drug used to treat rheumatoid arthritis and other inflammatory conditions. After a large post-marketing safety trial the FDA had required, the agency warned in 2019 of a higher risk of blood clots and death at certain doses, and in 2021 required an updated boxed warning — its most serious — for an increased risk of serious heart-related events like heart attack and stroke, cancer, clots and death, compared with an alternative class of arthritis drugs. The warnings were extended to other JAK inhibitors as well.

A boxed warning does not mean a drug is banned; it means prescribers and patients must weigh serious risks, often reserving the drug for people who did not respond to other treatments.

The Litigation

Following the warnings, some patients who suffered heart attacks, strokes, blood clots or cancer while taking Xeljanz began filing lawsuits, alleging that Pfizer failed to adequately warn of these risks earlier. This litigation is at an emerging stage: the cases have not been consolidated into a large multidistrict litigation, and there has been no major settlement or landmark verdict. Whether the litigation grows will likely depend on how many claims are filed and how early courts treat the causation and warning questions.

As with other drug cases, the central fights are when the maker knew of the risk and whether an individual’s injury can be tied to the medication.

What Patients Should Know

If you take Xeljanz, do not stop on your own — abruptly stopping an arthritis medication can cause a flare, and the decision should be made with your doctor, who can weigh your personal risk factors and alternatives. If you have had a serious heart event, clot or cancer while on the drug, keep your records and discuss it with your physician. Be cautious of ads promising compensation in an area where the litigation is still unsettled.