Dr. Thompson on the Results of the BRUIN Study in Patients With Richter's Transformation

Meghan Thompson, MD, third-year fellow, Hematology and Medical Oncology, Memorial Sloan Kettering Cancer Center, discusses the results of the phase 1/2 BRUIN study (NCT03740529) in patients with Richter transformation.

Findings from the BRUIN trial, which were presented during the 2021 International Workshop on CLL, showed that the investigational noncovalent BTK inhibitor pirtobrutinib (LOXO-305) elicited an overall response rate of 67%, which comprised 2 complete responses and 8 partial responses, among 15 evaluable patients with Richter transformation.

The presence of Richter transformation is associated with high-risk disease and poor outcomes, Thompsons says. Additionally, the patients included on the BRUIN study received a median of 4 prior lines of therapy for chronic lymphocytic leukemia prior to Richter transformation and a median of 2 prior lines of Richter transformation–directed therapy. Therefore, this population had very high-risk, heavily pretreated disease.

Additional results showed that the median time to best response was 1.9 months (range, 1.6-2.1), Thompson adds. Although longer follow-up is needed, these data suggest a promising role for pirtobrutinib in patients with Richter transformation, Thompson concludes.