lilly’s Pirtobrutinib Demonstrates Significant Progression-Free Survival Benefit in First-Line CLL/SLL Treatment
INDIANAPOLIS, IN – September 8, 2025 – Patients newly diagnosed with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) experienced a statistically significant improvement in progression-free survival (PFS) when treated with pirtobrutinib, a first-in-class non-covalent Bruton’s tyrosine kinase (BTK) inhibitor, according to results from the Phase 3 BRUIN CLL-313 trial.the findings bolster the potential of pirtobrutinib as a key treatment option for individuals with these blood cancers, even before prior therapies have been administered.
Currently,treatment options for CLL/SLL are evolving,and this data offers a promising new avenue for patients. The BRUIN CLL-313 trial results, alongside those from the BRUIN CLL-314 trial, are expected to support a label expansion for pirtobrutinib, allowing its use earlier in the treatment pathway - including for those who haven’t received BTK inhibitor therapy previously.This is especially significant as pirtobrutinib’s unique mechanism of action, as a non-covalent BTK inhibitor, may overcome resistance observed with other BTK inhibitors.
while overall survival (OS) data is still maturing, initial trends indicate a favorable outcome for patients receiving pirtobrutinib, with a primary OS analysis anticipated in 2026. The safety profile observed in the BRUIN CLL-313 trial remained consistent with previously reported studies.
“The results from BRUIN CLL-313 are striking and provocative, across both PFS and OS endpoints, further demonstrating the potential of pirtobrutinib to be a meaningful treatment option for peopel with untreated CLL/SLL,” stated Jacob Van Naarden, executive vice president and president of Lilly Oncology. “With this third positive phase 3 study, we continue to build the clinical evidence supporting the possible role of pirtobrutinib in a variety of CLL/SLL treatment settings, including treatment-naïve, BTK inhibitor-naïve and BTK inhibitor exposed.”
Full study results will be presented at an upcoming medical congress and submitted for publication in a peer-reviewed journal.
