Key takeaways: • A clinical trial led by Ohio State found the drug pirtobrutinib worked as well as another drug, ibrutinib, in the treatment of chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). • These findings are significant as it indicates that pirtobrutinib could be chosen as the first Bruton tyrosine kinase inhibitor for select patients with CLL and SLL who have stopped responding to other therapies. • Researchers shared these findings at the American Society of Hematology annual meeting in Orlando, and the study also was simultaneously published in the Journal of Clinical Oncology. COLUMBUS, Ohio – A study led by The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James) found the drug pirtobrutinib worked as well as another drug, ibrutinib, in the treatment of chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL), and people in the study responded better with pirtobrutinib. Ibrutinib was the first in a class of drugs known as Bruton's tyrosine kinase inhibitors (BTKi), and pirtobrutinib is the latest drug in that class to be used to treat certain blood cancers. In the last few years, the team at Ohio State have played a vital role in the research and development of these BTKi therapies. BTK inhibitors work by blocking an enzyme which plays a role in B-cell growth and proliferation in CLL and SLL. Researchers recently shared these findings during the press program at the American Society of Hematology (ASH) annual meeting in Orlando. The study also was simultaneously published in the Journal of Clinical Oncology. Jennifer Woyach, MD, director of Hematology at the OSUCCC – James, presented these findings during the ASH press program and was first and corresponding author on the published study. “These findings are significant as it indicates that pirtobrutinib could be chosen as the first Bruton tyrosine kinase inhibitor for select patients with CLL and SLL,” said Woyach, also a professor at Ohio State College of Medicine. What is CLL and SLL? CLL and SLL are slow-growing forms of non-Hodgkin lymphoma that develop when lymphocytes grow out of control and abnormal B cells build up in bone marrow or lymph nodes. CLL is the most common leukemia in adults with the average age of diagnosis being 70. Treatment options for CLL and SLL have evolved over the years to include therapies that target cancer cells which have grown resistant to certain therapeutics. Study design and data: This study is the first phase III clinical trial to directly compare a non-covalent BTK inhibitor to a covalent BTK inhibitor in patients with CLL or SLL. It included patients who had not received any previous treatment, a first for any phase III study directly comparing BTK inhibitors, as well as patients who had their cancer come back or not respond after receiving treatments other than a covalent BTK inhibitor. The study included 662 participants with CLL or SLL. Of those, 225 had not received any prior treatments, and 437 had become resistant to prior treatments and had not received any BTK inhibitors. Participants randomly received either pirtobrutinib or ibrutinib and remained on the assigned therapy unless their disease progressed or they experienced intolerable side effects. The overall response rate was 87% among those receiving pirtobrutinib and 78.6% among those receiving ibrutinib. Survival without disease progression will be studied at a later time. Woyach said future clinical trials could help define the use of pirtobrutinib alone or in combination with other therapies as a frontline treatment for CLL or SLL. Disclosures: This study was funded by Eli Lilly and Company, maker of pirtobrutinib. Woyach discloses that she has a consulting or advisory role with the following: Pharmacyclics, Janssen, AstraZeneca, BeiGene, Loxo, Newave Pharmaceutical, Genentech, AbbVie, and Merck. To learn more about Ohio State’s presence and presented studies on blood cancers and benign hematology at ASH, visit https://lnkd.in/g5zqE4je. To learn more about cancer treatment and clinical trials at the OSUCCC – James, visit cancer.osu.edu or call 1-800-293-5066. Media Contact: Mary Ellen Fiorino, Mary.Fiorino@osumc.edu