Adding ofatumumab to bendamustine did not improve survival in patients with rituximab-refractory indolent non-Hodgkin lymphoma (iNHL), according to study results published in the British Journal of Haematology.
The phase 3 COMPLEMENT A + B trial (ClinicalTrials.gov Identifier: NCT01077518), enrolled 346 patients with iNHL whose disease did not respond to or progressed on a prior rituximab-based regimen.
Most patients (67%) had follicular lymphoma, 14% had small lymphocytic lymphoma, and 11% had marginal zone lymphoma. The median age was 62 years, and 59% of patients were men.
The patients were randomly assigned 1:1 to receive ofatumumab plus bendamustine or bendamustine monotherapy. Baseline characteristics were well balanced between the treatment arms.
There was no significant difference in median progression-free survival between the combination arm and the monotherapy arm —16.7 months and 13.8 months, respectively (hazard ratio [HR], 0.82; 95% CI, 0.62-1.07; P =.1390).
Likewise, there was no significant difference in median overall survival between the combination arm and the monotherapy arm — 58.2 months and 51.8 months, respectively (HR, 0.89; 95% CI, 0.63-1.25; P =.4968).
No new safety signals were identified. The most common treatment-related adverse events (AEs) of any grade in both treatment arms were nausea, neutropenia, and fatigue.
The rate of serious treatment-related AEs was 22% in the combination arm and 30% in the monotherapy arm. AEs that resulted in permanent discontinuation of the study drug in both arms included neutropenia, thrombocytopenia, anemia, and leukopenia.
The researchers noted that the survival results in this study contrast with results from the GADOLIN study (ClinicalTrials.gov Identifier: NCT01059630), which showed that adding obinutuzumab to bendamustine significantly improved outcomes.
“The difference in the outcome could be due to multiple factors, including duration of maintenance therapy, and a difference in the MOA [mechanism of action] of the anti-CD20 antibodies,” the researchers wrote.
Disclosures: This research was supported by Novartis Pharma AG. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Rummel MJ, Janssens A, MacDonald D, et al. A phase 3, randomized study of ofatumumab combined with bendamustine in rituximab-refractory iNHL (COMPLEMENT A + B study). Br J Haematol. 2021;193(6):1123-1133. doi:10.1111/bjh.17420