Pfizer snags world-first atopic dermatitis nod for Xeljanz follow-up Cibinqo amid FDA safety delay

As the FDA delays decisions on several JAK inhibitors over safety concerns, its U.K. counterpart has moved forward to grant a new Pfizer drug its first approval worldwide.

Pfizer’s JAK inhibitor Cibinqo, also known as abrocitinib, has won an approval to treat moderate to severe atopic dermatitis, or eczema, from the U.K. Medicines and Healthcare products Regulatory Agency, the company said Thursday.

Notably, the nod covers both the 100mg and 200mg doses of Cibinqo. After a postmarketing trial linked Pfizer’s other JAK inhibitor, Xeljanz, with increased risks of heart-related side effects and cancer, concerns have increased over the approvability of JAK drugs, especially at high dosing strengths.

Following the nod, Pfizer’s priority is to work with the National Institute for Health and Care Excellence and the Scottish Medicines Consortium to ensure routine access to Cibinqo, Pfizer’s biopharmaceuticals group president Angela Hwang said in the statement.

Pfizer ran a family of clinical trials dubbed JADE to support its Cibinqo filings. In the first group of trials to read out, the drug showed it could top placebo in clearing the skin. In a more important win, Pfizer said a few days ago that the phase 3 JADE DARE trial found 200mg Cibinqo, a once-daily oral tablet, beat Sanofi and Regeneron’s blockbuster injection drug Dupixent in reducing itch and helping patients achieve near complete skin clearance.

RELATED: Pfizer's abrocitinib beats blockbuster Dupixent in phase 3 eczema trial, but key questions remain

Pfizer has pegged Cibinqo’s peak sales potential at $3 billion, arguing that a large number of atopic dermatitis patients aren’t getting a systemic agent. During a conference call with investors last October, Hwang said that gaining even only an 8% share of the systemic atopic dermatitis market would mean $3 billion in revenues for Cibinqo at peak.

But that rosy outlook looks shaky after the FDA last week slapped new safety warnings and use restrictions on Xeljanz as well as AbbVie’s Rinvoq and Eli Lilly’s Olumiant. The FDA is updating boxed warnings for the drugs to include language about the risk of serious heart-related events, cancer, blood clots and death. In a more damning move, the FDA is limiting approved use of the drugs to patients who have tried but failed on at least one TNF blocker.

RELATED: FDA's new JAK safety restrictions spell trouble for AbbVie's Rinvoq, but to what extent?

The restrictions spell trouble for Cibinqo, because the FDA is viewing the safety signals as a class-wide problem, even though the drugs target different members of the Janus kinase (JAK) family of enzymes. While Xeljanz seems to target JAK3, with weaker actions on JAK1 and JAK2, Cibinqo is designed as a specific JAK1 inhibitor and so is Rinvoq. In a note last Wednesday following the FDA’s announcement, SVB Leerink analyst Geoffrey Porges said he expects Cibinqo will get the same restrictions and labeling language.

After one FDA postponement in April, the agency again pushed back the med's atopic dermatitis application in July. The drug doesn't have a new known PDUFA data.