BRUIN Study Shows Pirtobrutinib’s Efficacy/Safety in CLL/SLL

Jennifer A. Woyach, MD, hematologist-oncologist, professor, the Division of Hematology, the Ohio State University Comprehensive Cancer Center– James, provides an overview on some of the updated safety and efficacy data observed with pirtobrutinib (Jaypirca) in the phase 1/2 BRUIN study (NCT03740529).

Heavily pretreated patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) were enrolled in the study and given pirtobrutinib after previous treatment with a covalent Bruton tyrosine kinase (BTK) inhibitor.

In this video, Woyach discusses the response rates and trends observed across patient subgroups, and provides an overview on some of the adverse events that have been observed with pirtobrutinib treatment in this space.

Transcription:

0:10 | We looked further at response rate in some different patient subgroups between the BCL2-naive and the BCL2-exposed subgroup. There were not a lot of surprising trends there. There was a trend toward a lower response rate in patients with [phospholipase C gamma1 (PLCG1)] mutations. That is the protein immediately downstream of BTK, and [one] would expect that a mutation there might lead to a lower response rate. Importantly, higher-risk characteristics, so things like TP53 alterations [or] IGHV-unmutated disease, did not seem to affect response rate.

0:40 | Pirtobrutinib has been exceptionally well-tolerated in clinical trials. Most of the toxicities are grades 1 and 2. The more common things we see are some kind of common toxicities. In general, people tend to sometimes have some gastrointestinal [adverse] effects. Bruising is pretty common, [and] neutropenia was fairly common among the cytopenia toxicities. When looking at adverse events of special interest, for things that we think about with BTK inhibitors like atrial fibrillation, hypertension, bleeding rates, all of those were very low. There was about a 4% rate of atrial fibrillation, but a 4% risk of higher-grade hypertension, and high-grade bleeding was about 2%.