Pfizer's Xeljanz jumps into ulcerative colitis fray with best-case FDA approval

Xeljanz is on a roll. The Pfizer immunology blockbuster scored a big new approval in psoriatic arthritis last year, and now it has won an FDA green light to treat ulcerative colitis—a big new market that could significantly pad its sales.

With its Wednesday approval, Xeljanz became the first drug in its class of JAK inhibitors cleared for the intestinal disease. And what’s more, the FDA blessed its larger 10-mg dose despite questions its staffers raised about safety.

FDA reviewers had expressed concerns about the safety of the higher dose and supported an approval for the 5-mg dose instead. But the FDA Advisory Committee, which was convened to weigh Xeljanz data, unanimously rallied behind both doses in a move that Leerink Partners analyst Geoffrey Porges predicted at the time “may force their hand in approving a broader label than we originally anticipated.”

Now, Pfizer has that broad label. Patients are directed to take Xeljanz 10 mg twice-daily for at least eight weeks, at which point they can either stay on the high dose or switch to the 5-mg dose.

RELATED: Pfizer takes on Novartis, Lilly with Xeljanz psoriatic arthritis approval

And it’s got a broad patient population, too. Ulcerative colitis affects about 907,000 U.S. patients, according to the New York pharma giant.

That’s not to say Xeljanz doesn’t have plenty of competition in the ulcerative colitis field. For one, it’s facing down anti-TNF giants, including AbbVie’s Humira and Johnson & Johnson’s Remicade, and in some cases, their biosimilars. Other competitors are on the way, too. Celgene’s ozanimod, a closely watched prospect also in development for multiple sclerosis, is among them.

Still, it’s a welcome nod for Pfizer, which has worked hard to widen Xeljanz’ reach The product, part of Pfizer’s blockbuster club and originally approved as a rheumatoid arthritis therapy, pulled in $1.35 billion in 2017—and most of those sales came before the company snagged that psoriatic arthritis OK from the FDA in December.