Pfizer has begun the first Phase III trial of tilrekimig, an investigational trispecific antibody concurrently neutralising IL-4, IL-13 and TSLP, in moderate-to-severe atopic dermatitis. The randomised, double-blind, placebo-controlled study (n=375) in patients aged 12 and older uses EASI-75 response and vIGA-AD 0/1 at week 16 as co-primary endpoints, with a projected monthly subcutaneous dosing schedule.

Tilrekimig is one of only four trispecific antibodies in global Phase III development and the sole trispecific targeting atopic dermatitis, occupying a mechanistic white space between dupilumab (IL-4Rα) and tezepelumab (TSLP).

Phase II data showed placebo-adjusted EASI-75 rates of 38.7%, 51.9% and 49.4% for low, middle and high monthly doses respectively at week 16, with conjunctivitis incidence lower than historical IL-4Rα inhibitor rates and no dose-dependent safety signal. By layering TSLP blockade onto the validated IL-4/IL-13 axis, Pfizer aims to capture both type-2 and non-type-2 inflammation drivers in one molecule.