A Study of Pirtobrutinib (LOXO-305) Versus Ibrutinib in Participants With Chronic Lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL)

Summary

The purpose of Part 1 of this study is to compare the efficacy and safety of pirtobruitinib (LOXO-305) to ibrutinib in participants with CLL/SLL; participants may or may not have already had treatment for their cancer. The purpose of Part 2 of this study evaluates pirtobrutinib monotherapy in treatment-naïve participants with CLL/SLL with 17p deletions. Participation could last up to six years for Part 1. Participation could last up to 2 years for Part 2.

Timeline

Start

2022-07-22

Primary completion

2027-10

Completion

2028-01

Outcome

Met primary endpoint

paper The study met its primary end points, demonstrating statistically significant noninferiority (NI) of IRC-ORR for pirtobrutinib versus ibrutinib PMID 41353787 ↗

paper two-sided P < .0001 PMID 41353787 ↗

Publications

• Eyre TA, Hess LM, Masoudi E, Jen MH, Abhyankar S, Graham-Clarke PL, Bhandari NR, Maguire P, Winfree KB, Tracey M, Taipale KL, Davids MS. Efficacy of Pirtobrutinib Monotherapy in Treatment-Naive Chronic Lymphocytic Leukemia: A Bayesian Network Meta-Analysis of Randomized Controlled Trials. Cancers (Basel). 2026 Feb 18;18(4):660. doi: 10.3390/cancers18040660.
• Woyach JA, Qiu L, Grosicki S, Wrobel T, Capra M, Czyz J, Yi S, Eom KS, Panovska A, Jurczak W, Laribi K, Jacobasch L, Baker R, Agajanian R, Berkovits A, Ozcan M, Lepretre S, Coombs CC, Cramer P, Lewis KL, Hill M, Bao K, Bian Y, De Batista Ribeiro SR, Bhandari NR, Ruppert AS, Leow CC, Wierda WG. Pirtobrutinib Versus Ibrutinib in Treatment-Naive and Relapsed/Refractory Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma. J Clin Oncol. 2026 Feb 20;44(6):476-485. doi: 10.1200/JCO-25-02477. Epub 2025 Dec 7.

Drugs

Evaluation	Drug	Modality	Dose	Route
Comparator	Ibrutinib	Small molecule	—	Oral
Subject	Pirtobrutinib	Small molecule	—	Oral

Indications