A new post-marketing Xeljanz drug safety study was ordered by the FDA after the drug was approved for multiple conditions including psoriatic arthritis, rheumatoid arthritis, ulcerative colitis, and juvenile idiopathic arthritis. The results revealed more serious side effects than originally believed, and the drug’s makers were forced to release new health alerts due to these findings.

The FDA doubled down on these safety concerns in early February 2021. The study found that Xeljanz causes heart problems and even cancer. These adverse effects were added to the drug label in July 2019.

After the initial Xeljanz drug safety study, Pfizer switched patients to the higher dose of 5 mg, citing a missed primary endpoint. In addition to missing the primary endpoints, the study failed to show any significant differences in the risk of cardiovascular and cancer events between the two doses. Several JAK inhibitors have been the subject of warnings from the FDA, including an increased risk of blood clots and heart failure. In addition to this, the FDA has also issued a black box warning for the drug.

The FDA issued a drug safety communication addressing the risk of serious heart problems associated with Xeljanz after the drug’s safety clinical trial was completed. In February 2021, the FDA released a drug safety communication about the Xeljanz drug after the release of the new safety clinical trial results. Despite the Xeljanz safety study, the FDA continues to investigate the issue and may take further regulatory action. A Xeljanz safety study may ultimately lead to a recall of the drug.

In the post-marketing Xeljanz study, patients were given a TNF inhibitor as a comparator. Patients in the TNF inhibitor group experienced fewer cardiovascular events, but their cancer risk increased significantly. In the Post-marketing Xeljanz safety study, Pfizer continues to monitor the safety of the drug. In the meantime, it is important to know what to expect. The Xeljanz safety study is the best available proof of its effectiveness and safety.

Xeljanz has been subjected to a review by Health Canada before. During that review, it was linked to an increased risk of blood clots in the lungs and even death. Health Canada worked with Pfizer to amend the drug’s label, adding a warning that explains the risk of thrombosis. These results should be interpreted with caution, but Pfizer needs to reassure patients and physicians that the drug is safe. The drug’s negative safety outcomes will undoubtedly lead to longer boxed warnings in the US.