CHICAGO – Overall survival was comparable at 5 years of follow up for three regimens in treatment-naive patients with indolent non-Hodgkin lymphoma (NHL) or mantle cell lymphoma (MCL), based on long-term results from the BRIGHT study.
While progression-free survival, event-free survival, and duration of response were significantly better with bendamustine plus rituximab (BR), overall survival at 5 years did not significantly differ in patients given this regimen and compared to patients given rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or rituximab with cyclophosphamide, vincristine and prednisone (R-CVP),, of Tennessee Oncology, Nashville, reported at the annual meeting of the American Society of Clinical Oncology.
Quality of life was somewhat better for the patients given BR, but those patients were also at higher risk for secondary malignancies (42 vs. 24), most of which were squamous cell carcinomas, observed Dr. Kahl, professor of medicine at Washington University, St. Louis.
In BRIGHT, 224 treatment-naive patients with indolent NHL or MCL were randomized to receive BR and were compared to 223 similar patients who received either R-CHOP (104 patients) or R-CVP (119 patients). At least six cycles of therapy were completed by 203 patients in the BR group and by 196 in the R-CHOP/R-CVP group. Rituximab maintenance therapy was given to 43% of the BR group and to 45% of the R-CHOP/R-CVP group.
For BR and R-CHOP/R-CVP, the 5-year progression-free survival rate was 65.5% (95% CI, 58.5-71.6) and 55.8% (95% CI, 48.4-62.5), respectively. The overall survival rate for the entire patient group was 81.7% (75.7-86.3) and 85% (79.3-89.3) respectively. Comparing BR and R-CHOP/R-CVP, the hazard ratio (95% CI) for progression-free survival was 0.61 (0.45-0.85; P = .0025), the HR for event-free survival was 0.63 (0.46-0.84; P = .0020), the HR for duration of response was 0.66 (0.47-0.92; P = .0134), and the HR for overall survival was 1.15 (0.72-1.84; P = .5461).
Similar results were found in indolent NHL (progression-free survival 0.70 [0.49-1.01; P = .0582]) and MCL (progression-free survival 0.40 [0.21-0.75; P = .0035]), with the strongest effect in MCL, Dr. Flinn said.
Dr. Kahl noted that the advantages for the BR regimen include that it is not associated with alopecia, neuropathy, or steroid issues, and that it may extend progression-free survival and time to next treatment. On the other hand, R-CHOP is associated with less GI toxicity, rash, opportunistic infections, and prolonged cytopenia. Also, the BR regimen was associated with a higher risk of secondary cancers, primarily squamous cell carcinomas.
There were 42 secondary malignancies in the BR group and 24 in the R-CHOP/R-CVP group, Dr. Flinn reported.
It is theoretically possible that BR equals R-CHOP plus maintenance therapy from an efficacy perspective, Dr. Kahl said.
As virtually all excess adverse event fatalities occurred during maintenance therapy, it is possible that maintenance therapy after BR “does more harm than good.” This high priority issue “should be evaluated in the BRIGHT data set,” Dr. Kahl recommended.
Teva Branded Pharmaceutical Products R&D sponsored the study. Dr. Flinn had no relationships to disclose; two of his fellow researchers are Teva employees. Dr. Kahl disclosed serving as an adviser or consultant to Abbvie, Acerta Pharma, Celgene, Cell Therapeutics, Genentech/Roche, Incyte, Infinity Pharmaceuticals, Juno Therapeutics, Millennium, Pharmacyclics, Sandoz, and Seattle Genetics.