ORLANDO — A debulking strategy using obinutuzumab with or without bendamustine could allow more patients with chronic lymphocytic leukemia to receive venetoclax in the outpatient setting, “eliminating the need for hospitalization during venetoclax initiation,” according to researchers at the ASH Annual Meeting and Exposition.
Patients with CLL initiating frontline treatment with venetoclax (Venclexta; AbbVie, Genentech) are at risk for developing tumor lysis syndrome (TLS), a potentially life-threatening condition that occurs during the rapid induction of cell death, according to Jeff P. Sharman, MD, director of research at Willamette Valley Cancer Institute and medical director of hematology research for the US Oncology Network. To address this risk, Sharman and colleagues assessed the efficacy of a debulking strategy, during which patients received obinutuzumab (Gazyva, Genentech) alone or in combination with bendamustine to reduce tumor burden before receiving venetoclax.
At the time data were presented, 96 treatment-naive patients with CLL and a medium-to-high tumor burden received either obinutuzumab (71%) or the combination of obinutuzumab plus bendamustine (29%). Among them, 79 patients completed two cycles of the debulking regimen and received venetoclax.
After two cycles, 87% of patients had a low TLS risk, including 89% of evaluated patients in the obinutuzumab monotherapy group and 81% of patients in the combination group. Adding bendamustine increased the efficacy of the debulking strategy among patients with 5 cm to 10 cm lymph nodes, according to the researchers. The strategy was generally safe and the observed safety profiles for obinutuzumab, bendamustine and venetoclax were consistent with previous safety data.
“In general, I think this strategy was quite effective,” Sharman told Healio. “There is already FDA approval for the combination of obinutuzumab-venetoclax. ... If [treating physicians] want to do debulking before starting venetoclax, this should give them some nice granularity for how effective that is, and in what patients it works well.”
Sharman JP, et al. Abstract 3042. Presented at: ASH Annual Meeting and Exposition; Dec. 7-10, 2019; Orlando.
Disclosure: Sharman reports advisory/consultant roles with and honoraria and research funding from AbbVie, Acerta, AstraZeneca, Genentech, Janssen, Juno Therapeutics, Pfizer and TG Therapeutics.