Research in context
Evidence before this study
When the study protocol was developed in 2009, little data for the efficacy and safety of maintenance treatment in chronic lymphocytic leukaemia existed. We searched PubMed without restrictions of time of publication using the terms “CLL AND maintenance” and “CLL AND consolidation”, without time or language restrictions. We identified two studies, both in previously untreated patients: consolidation (4 months) and maintenance (12 months) with rituximab was assessed in a phase 2 trial, and consolidation (3 months) with alemtuzumab was tested in a phase 3 study. The phase 3 study was stopped prematurely because of severe infections.
Added value of this study
This study is the first large, randomised, phase 3 study of maintenance treatment in a population of patients with relapsed chronic lymphocytic leukaemia in remission after re-induction treatment. We show that 2 years of maintenance treatment with ofatumumab, a human anti-CD20 monoclonal antibody, prolonged progression-free survival and time to next treatment. Ofatumumab was well tolerated and did not cause unexpected toxicities. Importantly, we show that ofatumumab maintenance did not increase the risk of transformation.
Implications of all the available evidence
Our data are timely in the present era of novel treatment modalities for chronic lymphocytic leukaemia, notably the BTK and PI3K inhibitors. At present, continued treatment with these kinase inhibitors until relapse is recommended—ie, they are used as a prolonged maintenance treatment. Our data for the efficacy and safety of ofatumumab maintenance treatment are important for the determination of the optimum maintenance strategies in relapsed chronic lymphocytic leukaemia.