Pfizer Inc details 61% EASI‑75 response in tilrekimig trial

A Phase 2 EASI-75 response reached 61.0 per cent with a monthly tilrekimig dose, as Pfizer Inc. NYSEPFE reported detailed atopic dermatitis results on Thursday. At Week 16, the 200 mg group reached the endpoint against 9.1 per cent on placebo. Pfizer reported a p value below 0.003.

Pfizer had announced a positive topline on March 9. Thursday's release added response rates by dose and said patients have already been dosed in two Phase 3 atopic dermatitis studies, including one that compares tilrekimig directly with dupilumab.

Pfizer is a large New York drugmaker that sells medicines and vaccines worldwide. Its investigational tilrekimig antibody targets three inflammatory signals involved in atopic dermatitis.

Pfizer shares NYSEPFE closed at US$28.52 in New York on Sept. 30, as of 4:02 p.m. EDT on the quote page. That close preceded the Oct. 1 disclosure, so it does not measure the market's response to the detailed data.

Monthly Doses Beat Placebo at Week 16

The registered study, NCT05995964, is a randomized, blinded trial with several stages. Thursday's results covered biologic-naive adults in the first two stages; a separate stage tests participants previously treated with biologics. EASI-75 means at least a 75 per cent improvement in the Eczema Area and Severity Index, rather than completely clear skin.

In the first stage, 62.5 per cent on 450 mg every two weeks reached the endpoint. Placebo response was 19.9 per cent, with a p value of 0.0008. In the monthly-dose stage, the 400 mg group recorded a 58.5 per cent response. The 50 mg group recorded 47.8 per cent. Placebo response was 9.1 per cent, and Pfizer reported a p value below 0.003 for each monthly dose.

On a stricter measure of clear or almost clear skin with an improvement of at least two grades, 26 to 27 per cent of monthly-dose recipients responded. None on placebo did, and Pfizer reported p values below 0.006. The dose-level results add detail to the March topline, but the study still compares each dose with placebo rather than an approved biologic.

Treatment-emergent adverse events occurred in 46.7 per cent of the 450 mg group and 28.9 per cent of its placebo group. In the monthly-dose stage, rates ranged from 42.2 to 47.8 per cent on tilrekimig, against 52.2 per cent on placebo. Pfizer reported no treatment-related serious adverse events in the two stages presented.

"Building on these promising findings, we have initiated Phase 3 trials of tilrekimig in atopic dermatitis and asthma, and we are advancing a Phase 2b/3 study in COPD," Pfizer chief inflammation and immunology officer Michael Vincent said in the Oct. 1 release.

The Direct Comparator Comes in Phase 3

Pfizer is testing whether blocking interleukin-4, interleukin-13 and TSLP can yield a useful monthly option. The Phase 2 figures cannot establish superiority to dupilumab because that medicine was not a treatment arm in the reported stages. The active-comparator Phase 3 study will provide the direct evidence investors need to assess that claim.

In the listed dermatology peer set, Sanofi SA NASDAQSNY closed at US$41.23 on Sept. 30, as of 4:00 p.m. EDT on its quote page. Pfizer's new percentages arrive amid fresh skin-disease readouts across the sector, though rates from different diseases and trial designs cannot be compared head to head.

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Patients have also been dosed in a Phase 3 asthma study, while a Phase 2b/3 COPD study is advancing, Pfizer said on Oct. 1. The company gave no Phase 3 readout date in that release. Results from the atopic dermatitis trial with a dupilumab arm will decide whether tilrekimig's monthly regimen can compete directly with an established biologic.