Pfizer, Lilly bolster cases for experimental ulcerative colitis drugs
Etrasimod and mirikizumab are important drugs to their respective makers. For Pfizer, etrasimod was the primary draw in its nearly $7 billion acquisition of Arena Pharmaceuticals last December.
The company aims to file for approval with the FDA later this year and sees potential for the drug in an array of other inflammatory diseases.
Lilly, meanwhile, has already asked the FDA to approve mirikizumab and is currently awaiting the agency’s decision on approval, which is likely to come in 2023. If approved, the drug would add to Lilly’s portfolio of immunology medicines, currently headlined by the arthritis and psoriasis treatment Taltz.
Both Pfizer’s and Lilly’s drugs are aimed at moderate-to-severe ulcerative colitis. Most of the patients in Pfizer’s trials had not previously taken other drugs like biologics or so-called JAK inhibitors for their condition, while Lilly studies enrolled patients who needed additional treatment after other drugs failed.
The two drugs also work differently. Etrasimod is what’s known as a S1P receptor modulator and, if approved, would join Bristol Myers Squibb’s Zeposia on the market. Mirikizumab, by comparison, works by blocking a specific part of a protein known as IL23p19. It would be the first of its type for ulcerative colitis if cleared by the FDA, according to Lilly. (Other anti-IL23 drugs are approved for psoriasis, an indication which Lilly last year deprioritized for mirikizumab.)
There are a range of treatment options for ulcerative colitis currently, including older biologic therapies like Humira as well as the JAK-blocking drugs Xeljanz and Rinvoq. But not all patients respond well, or continue to respond over time, to those treatments — a problem drugmakers like Pfizer and Lilly hope to solve by developing etrasimod and mirikizumab as additional options.
In Pfizer’s trials, treatment with etrasimod led to clinical remission in significantly more patients than did placebo: 27% versus 7%, respectively, at week 12 and 32% versus 7% at week 52 in Elevate UC 52. In Elevate UC 12, the rates of remission were 25% for the etrasimod-treated group compared to 15% for those given a placebo.
Pfizer reported that “treatment-emergent” side effects were similar between etrasimod and placebo, although there were higher rates on headache, worsening of ulcerative colitis, COVID-19, dizziness, fever, abdominal pain and nausea among those given the drug. Lilly’s study involved patients who responded to mirikizumab treatment in a previous study and assessed whether treatment responses maintained through one year. At 52 weeks, nearly 50% of mirikizumab-treated patients were in remission, versus 25% of those given placebo.
Lilly described mirikizumab’s safety profile as “consistent” with prior studies and that of anti-IL23p19 drugs used for other diseases. The company reported a lower rate of serious side effects among those on its drug versus those given a placebo.
Published May 24, 2022
Ned PagliaruloLead Editor