At follow-up, median progression-free survival (PFS) was not reached, the 2-year PFS rate was 79% (95% CI, 65%–97%), and the 3-year PFS rate was 62% (95% CI, 45%–85%). The primary end point was best CR rate measured by PET-CT, including CR achieved during treatment; CT-based responses were also prospectively collected. The CR rate increased from 62.5% after 3 cycles to 92% after 6 cycles, leading to the best ORR of 100%. The 2-year PFS rate was 79%, and the 3-year PFS rate was 62%. Frontline acalabrutinib, lenalidomide and rituximab for advanced stage follicular lymphoma with high tumor burden: phase II trial.