Pirtobrutinib Produces Durable Responses in Pretreated MCL

Nirav Shah, MD, associate professor at the Medical College of Wisconsin, discusses long-term data from the phase 1/2 BRUIN study (NCT03740529) which evaluated pirtobrutinib (Jemperli) in mantle cell lymphoma (MCL) and next steps for evaluating the agent.

The FDA previously granted approval to pirtobrutinib in January 2023 for the treatment of adult patients with relapsed/refractory MCL who had received at least 2 prior lines of systemic therapy, including a Bruton’s tyrosine kinase (BTK) inhibitor. This approval was supported by findings from the phase 1/2 BRUIN study.

In the study, pre-treated patients with relapsed/refractory MCL given pirtobrutinib, a highly selective kinase inhibitor, achieved an overall response rate of 50%, and 13% of patients had a complete response at time of analysis.

During the 2023 ASCO Annual Meeting, Shah further discussed data from the study, highlighting the durable responses observed with pirtobrutinib in this patient population.

Transcription:

0:10 | I presented the longer-term MCL outcome data, which shows the median duration of response at 2-3 years of follow-up was a year and a half, which shows that if you are a responder to the drug that there is durability. That's important [because you] can't just take a pill and say it worked for 2 or 3 months. With longer follow-up, we're seeing that there are some patients that do get those durable responses, even in a refractory state.

0:37 | Now, I think a study that's going to be very interesting that we're participating in is the BRUIN-MCL study [NCT04662255], which is a head-to-head study of pirtobrutinib against covalent BTK inhibitors. If this drug works well, even after other BTK, maybe it's better BTK. That study is going to help us delineate that and if it is a positive study and pirtobrutinib shows better outcomes, we should be using it earlier in lines of therapy rather than saving it as our last option.