ASH 2023 | Pirtobrutinib in patients with CLL/SLL previously exposed to covalent BTKi: insights from BRUIN

Pirtobrutinib is a non-covalent, potent, highly selective BTK inhibitor which has efficacy in both wild type and C481-mutated CLL. Here we present the longer-term follow-up of the Phase I/II BRUIN study, focusing on the almost 300 patients who had previously received a covalent BTK inhibitor. And kind of looking at that group, subclassified into those patients who had received a BCL2 inhibitor prior and those that had not.

We see for the whole cohort of patients, the median progression-free survival is 19.4 months. When looking at BTK inhibitor naive versus those that had been previously exposed to BTK inhibitors, I’m sorry that both exposed to BCL2 inhibitors, the response rate is pretty much the same in those two patient cohorts. Progression-free survival does look to be a little longer in the patients who had not previously been exposed to a BCL2 inhibitor, where those patients had a median progression-free survival of about two years, compared to about 16 months for those patients previously exposed to a BCL2 inhibitor. Looking at the safety data, really no new safety signals have emerged in this population. So again, looking very promising for pirtobrutinib in this population.