Drugs from the burgeoning JAK group have so far run into their fair share of safety liabilities, and if the label for new AbbVie med Rinvoq is any indication, the FDA now believes those issues are class-wide.
That’s an association that doesn’t bode well for up-and-comers—including Gilead’s closely watched filgotinib.
The FDA green-lighted Rinvoq Friday as expected, but it added a black-box warning—its most serious—to the drug’s label, cautioning patients of an “increased risk of serious infections, malignancy, and thrombosis,” SVB Leerink analyst Geoffrey Porges wrote in a Sunday note to clients.
It’s a warning consistent with those carried by its fellow JAKs, Pfizer’s Xeljanz and Eli Lilly’s Olumiant, despite Rinvoq “having a better safety profile in its pivotal trials,” Porges noted.
What’s more, the Rinvoq safety language doesn’t mention the drug's association with thrombosis events at all. “This suggests that the FDA now regards these events as class liabilities, regardless of what is reported from pivotal trials,” Porges said.
That’s a bad omen for drugs including Gilead’s filgotinib, “which is depending on greater JAK1 specificity, and lower adverse event liabilities, for its long-term positioning,” Porges wrote.
After an initial rejection, the FDA finally cleared Olumiant last year—but only at the lower of two proposed doses, and with a black-box warning to boot. Questions about broader JAK safety surfaced earlier this year when Xeljanz study data drew potential links between a higher, 10mg dose and life-threatening or fatal blood clots.
Ultimately, the agency decided to add a boxed warning to Xeljanz and nix its go-ahead in previously untreated ulcerative colitis patients, actions it took just a few weeks before Rinvoq’s debut.
Even saddled with safety challenges, though, analysts expect Rinvoq to reach the blockbuster threshold with ease. Porges and his team expect to see peak sales between $3 billion and $5 billion.
And RBC Capital Markets’ Brian Abrahams isn’t too worried about Rinvoq or filgotinib, either. The language on Rinvoq’s label “is much less strong than for Xeljanz or Olumiant, just referencing the class and advising providers consider benefit/risk in patients at risk for thrombosis,” he noted. “Overall even if filgotinib has a similar warning, it is also likely to be of less-impactful prominence.”