Page 107 - Haematologica Vol. 110 - January 2025

ARTICLE - Pirtobrutinib in patients with prior intolerance to BTKi N.N. Shah et al.
Similarly, of 3 patients who discontinued a prior cBTKi due to hypertension, one had grade 1 recurrence in this study. Overall, there was low frequency of pirtobrutinib discon- tinuations due to an AE. Discontinuation of pirtobrutinib due to TRAE occurred in 7 (5.5%) patients with B-cell ma- lignancies who were previously intolerant to BTKi, which was consistent with the 2.6% discontinuation rate due to TRAE seen among all patients treated with pirtobrutinib monotherapy in the phase I/II BRUIN study.
The data presented here suggest pirtobrutinib may be an option after cBTKi intolerance as no patient stopped pirtobrutinib for the same AE that had led to prior BTKi intolerance. These low rates of discontinuation after prior intolerance may be important in the clinical management of B-cell malignancies by allowing BTK inhibition to be main- tained without having to switch to another drug class.7 In addition, pirtobrutinib was highly efficacious and extended BTK inhibition for these prior BTKi-intolerant patients as
Haematologica | 110 January 2025
99
Figure 3. Progression-free survival in patients intoler- ant to prior Bruton tyrosine kinase inhibitor. Median pro- gression-free survival (PFS) for patients with chronic lymphocytic lymphoma (CLL) / small lymphocytic lympho- ma (SLL) was 28.4 months (95% Confidence Interval [CI]: 21.8-not estimable [NE]), while median PFS was not estimable for patients with mantle cell lymphoma (MCL). Median overall survival was not estimable for CLL/SLL or MCL.