Long-Term Remissions with MRD-Guided Acalabrutinib, Venetoclax and Obinutuzumab in Relapsed/Refractory CLL: Follow-up Efficacy and Circulating Tumor DNA Analysis of the CLL2-Baag Trial

Background The phase 2 CLL2-BAAG trial tested a triple combination of acalabrutinib (acala), venetoclax (ven) and obinutuzumab (obi) after an optional debulking with bendamustine in patients (pts) with relapsed/refractory (r/r) CLL. In its primary endpoint analysis, 75.6% of pts achieved undetectable MRD (uMRD) in peripheral blood (PB) at final restaging (RE) after approximately 6 months of the triplet (Cramer, Lancet Haematol. 2022). We now report efficacy data and circulating tumor DNA (ctDNA) analyses with additional follow-up. Methods In the induction phase, obi was started in cycle 1 (days 1, 8, 15) and given 4-weekly in cycles 2-6. Acala was added in cycle 2 and ven in cycle 3. Maintenance treatment with continuous acala and ven and 3-monthly obi was administered until achievement of a deep remission with uMRD