Pirtobrutinib Reaches 93% ORR and 93% 24-Month PFS in Frontline CLL/SLL

Pirtobrutinib is a selective, reversible, non-covalent BTK inhibitor evaluated as continuous monotherapy in treatment-naïve CLL/SLL using pooled pirtobrutinib arms from BRUIN CLL-313 and BRUIN CLL-314 (n=253; safety n=252). At ~27.7 months’ median follow-up, ORR was 93.3%, median PFS and OS were not reached, 24-month PFS was 93.2%, and 24-month OS was 97.5%. Safety showed low AE-driven discontinuation (4.8%; treatment-related 1.6%), grade ≥3 bleeding 2.4%, hypertension 10.7%, and atrial fibrillation/flutter 2.8%, which is the most important potential differentiator versus covalent BTKi experience.