Single-agent immunotherapy in patients with a subtype of relapsed or refractory diffuse large B-cell lymphoma (DLBCL) provides more clinical benefit than conventional therapy, according to research published in Clinical Cancer Research (online August 2017; doi:10.1158/1078-0432.CCR-16-2818).
Front-line standard of care for DLBCL is rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). While R-CHOP has shown the ability to improve clinical outcomes in DLBCL, 20% to 25% of patients relapse after initial response to therapy. Lenalidomide has previously demonstrated positive results in this population.
Myron S Czuczman, MD, Roswell Park Cancer Institute (Buffalo, NY), and colleagues conducted a randomized, multicenter, open-label, phase II/III trial to further investigate lenalidomide vs investigator’s choice therapy in relapsed or refractory DLBCL. A total of 102 patients who received at least two prior therapies were enrolled and stratified based on disease subtype – germline center B-cell (GCB, n = 48) vs non-GCB (n = 54). Patients were then randomized 1:1 to receive either lenalidomide (25 mg/day, 21 days of a 28-day cycle) or investigator’s choice (gemcitabine, rituximab, etoposide, or oxaliplatin). Crossover to the lenalidomide arm was permitted for patients with progressed disease during the trial.
The primary endpoint was overall response rate (ORR), and secondary endpoints included progression-free survival (PFS), overall survival, and subtype analysis (GCB vs activated B-cell) using gene expression profiling.
Results of the study showed that patients in the lenalidomide arm had an ORR of 27.5% compared with 11.8% for those in the investigator’s choice arm. Researchers noted that ORRs were similar among the GCB and non-GCB subtypes.
Furthermore, median PFS was increased in patients in the lenalidomide arm (13.6 weeks) compared with those in the investigator’s choice arm (7.9 weeks). Within this sub-analysis, greater improvements were observed in non-GCB patients (15.1 weeks vs 7.1 weeks, respectively) compared with GCB patients (10.1 weeks vs 9.0 weeks).
Authors of the study concluded that clinical benefit of lenalidomide monotherapy in patients with relapsed or refractory DLBCL was stronger for those with a non-GCB subtype. “Exploratory analyses suggest that this preferential benefit was more pronounced in the [activated B-cell] population, demonstrating a need for additional studies of lenalidomide in DLBCL using [gene expression profile] subtyping,” they wrote.—Zachary Bessette
