Xeljanz sales reached >$400 million last qtr for PFE. This exceeds what most expected from what is widely perceived as one of the weaker JAKS used for RA and also carries a higher risk of infections then the competition. But PFE has learned it pays off to be 1st out of the gate. Baricitinib has just arrived and soon GILD's & AbbVie's drugs will be out and will eventually cut into PFE's sales with more effective drugs. PFE chose to go with the weaker of its 2 AA drugs PF-06651600 over PF-06700841. The latter drug did have 2 AE cases of rhabdomylosis which appears to have removed the far more effective and faster acting AA drug.
>SALT change from baseline scores at Week 24 were 33.6 points for PF-06651600 and 49.5 points for PF-06700841, with statistically significant separation from placebo occurring as early as Week 6 and Week 4, respectively.<
My theory is PFE sees a similar opening in AA where a less effective drug can become a billion dollar drug by being the 1st in class to getting FDA approval. But imo the patients who have AA will have higher expectations then RA patients who were happy to use a less effective oral drug that didn't require an injection like Humira. AA patients won't be satisfied to have 50% of their hair grow back. I think they want a tx that gives >90% of their hair back. PFE will probably be 1st in AA but they won't have the same success they had with Xeljanz. Their reps will help CNCE by introducing to Dermatologists the concept of JAK therapy as a drug therapy for AA. But PFE's drug had very modest results & will fail the most important test for AA-the eyeball test.