JAK Inhibitors Get a Regulatory Reckoning (Boxed Warnings Expansion)
2019-02 to 2021-09What Happened
A large safety trial and subsequent FDA reviews linked certain JAK inhibitors to higher risks of serious cardiovascular events, cancers, blood clots, and death. FDA required boxed-warning revisions and narrowed the comfort zone for oral immune pathway drugs.
Outcome
Prescribing tightened and risk messaging became central to oral immunology launches.
“Safety optics” became a gating factor for any new oral immune modulator, including TYK2s.
Why It's Relevant Today
It explains why Takeda’s story is as much about safety/selectivity as headline clearance rates.
