FDA Hits JAK inhibitors With Heart Safety, Cancer Warnings: All You Need To Know

The FDA wrapped up its long-awaited review of Pfizer Inc's PFE large, randomized trial evaluating the safety of JAK inhibitors Xeljanz and Xeljanz XR compared to tumor necrosis factor (TNF) blockers.

What Happened: The agency said the trial results showed an increased risk of serious heart-related events such as heart attack or stroke, cancer, blood clots, and death with the lower dose of Xeljanz. But, previous interim results showed the risk only with the higher dose.

The FDA is updating JAK inhibitor labels while limiting their use to certain patients who are not treated effectively or experiences severe side effects with the TNF blockers. In this case, Eli Lilly And Co's LLY Olumiant and AbbVie Inc's ABBV Rinvoq are suffering collateral damage.

Why It Matters: As the FDA acknowledged, Olumiant and Rinvoq don't have large safety trials similar to that of Xeljanz's, "so the risks have not been adequately evaluated." 

But since Olumiant and Rinvoq "share mechanisms of action with Xeljanz, FDA considers that these medicines may have similar risks as seen in the Xeljanz safety trial," the agency said.

The news comes as the FDA review of several other indications for JAK inhibitors, including Rinvoq and Olumiant, were delayed due to this investigation into the Xeljanz trial.

Related Content: AbbVie, Lilly Atopic Dermatitis Treatments Hit With Further Delays With FDA.

But FDA said that two other JAK inhibitors, Incyte Corporations's INCY Jakafi and Bristol Myers Squibb & Co's BMY Inrebic, "are not indicated for the treatment of arthritis, and other inflammatory conditions and so are not a part of the updates.

Price Action: LLY stock closed 0.34% lower at $257.40 on Wednesday, ABBV stock is up 1.08% at $113.48, and PFE stock is +0.54% at $46.29 during the premarket session on the last check Thursday.