FDA warns of blood clots and death associated with higher dose of Pfizer's Xeljanz

The U.S. Food and Drug Administration is issuing a warning that a safety clinical trial found an increased risk of blood clots in the lungs and death when a 10 mg twice daily dose of tofacitinib (Xeljanz, Xeljanz XR) was used in patients with rheumatoid arthritis. The FDA has not approved this 10 mg twice daily dose for RA but has approved itin the dosing regimen for patients with ulcerative colitis.

In this ongoing safety trial required by the FDA when it approved tofacitinib for RA, Pfizer is transitioning patients who were on the high 10 mg twice daily dose to the lower, approved dose of 5 mg twice daily. This trial will continue and is expected to be completed by the end of 2019.

When the FDA first approved tofacitinib, it required a clinical trial among patients with RA to evaluate the risk of heart-related events, cancer and opportunistic infections with the medicine at two doses (10 mg twice daily and 5 mg twice daily) in combination with methotrexate in comparison to another drug called a tumor necrosis factor inhibitor. RA patients in the trial were required to be at least 50 years old and have at least one cardiovascular risk factor. During the most recent analysis of the trial, an external data safety monitoring committee found an increased occurrence of blood clots in the lungs and death in patients treated with tofacitinib 10 mg twice daily compared to patients treated with tofacitinib 5 mg twice daily or a TNF inhibitor.

Read the FDA safety announcement