Fenebrutinib and BTK inhibition: unveiling a new target for the treatment of chronic spontaneous urticaria

Fenebrutinib is an orally administered, selective and reversible BTK inhibitor. Metz et al recently published a double-blind, placebo-controlled, phase 2 trial where fenebrutinib (50mg daily, 150mg daily or 200mg twice-daily) or placebo were randomly administered to 93 adults with CSU refractory to up-dosed H 1 -antihistamines during 8 weeks. Fenebrutinib was more effective than placebo in reducing weekly Urticaria Activity Score (UAS7) after 8 weeks, achieving rates of well-controlled disease (UAS7≤6) of up to 57% (with a 200mg twice-daily dose).