COLUMBUS, Ohio – New Phase 3 clinical trial data presented earlier this month at the American Society of Clinical Oncology annual meeting showed that adding venetoclax to ibrutinib and obinutuzumab did not improve progression-free survival in older patients with chronic lymphocytic leukemia (CLL), the most common form of adult leukemia. The multicenter study, part of the Alliance for Clinical Trials in Oncology, was led by The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James) and examined whether adding venetoclax to the usual treatment of ibrutinib with obinutuzumab would improve outcomes for this patient population. “Our study demonstrates that the triple therapy, or adding venetoclax to ibrutinib and obinutuzumab as a course of treatment for older patients with CLL, is not superior in terms of progression-free survival,” said the study’s lead investigator Jennifer Woyach, MD, a hematologist with the OSUCCC – James and co-leader of the OSUCCC – James Leukemia Research Program. The Bruton’s tyrosine kinase inhibitor (BTKi) ibrutinib with obinutuzumab is a standard frontline treatment option for older adults with CLL, but it does not often lead to a complete response, so treatment is therefore given to patients indefinitely. Researchers continue to evaluate new medications and combinations of medication that would improve cancer control while not requiring lifelong treatment. The trial, sponsored by the National Cancer Institute, enrolled 465 patients ages 65 and older with previously untreated CLL. The trial participants were randomly assigned to two arms— one arm received ibrutinib and obinutuzumab (IO) and the other arm received venetoclax plus ibrutinib and obinutuzumab (IVO). At 18 months, the progression-free survival rate was 87% in the IO arm and 85% in the IVO arm. Further, due to the COVID-19 pandemic, 30 trial participants succumbed to complications from COVID-19. When these deaths were censored from study results, the progression-free survival rate was 92% in the IO arm and 94% in the IVO arm. “The pandemic had a clear impact on our trial, and long-term follow-up of our patients will be critical to determine the outcome of this triple therapy with special attention to minimal residual disease and therapy discontinuation,” said Woyach, also a professor of hematology in the Ohio State College of Medicine. Financial support for this study came in part from Pharmacyclics, AbbVie, Genentech and Abbott Molecular. Information about this study can be found here. To learn more about CLL research and patient cancer care at the OSUCCC – James, visit cancer.osu.edu/cll.                                                                                                                      ### Media Contact: Mary Ellen Fiorino, Wexner Medical Center Media Relations, Mary.Fiorino@osumc.edu