Adding rituximab and bortezomib to a moderate-intensity chemotherapy regimen and following it up with maintenance rituximab produced high response rates and “excellent” survival outcomes for adults with previously untreated mantle cell lymphoma (MCL), investigators reported in long-term follow-up of a small study.

The objective response rate (ORR) among 30 patients with MCL treated with VcR-CVAD – bortezomib (Velcade), rituximab, and hyperCVAD (hyper-fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) followed by rituximab maintenance – was 90%, including a high proportion of complete responses (CR) or unconfirmed complete responses.

After a median follow-up of 7.8 years, the rates of 6-year progression-free and overall survival (PFS and OS) were 53% and 70%, respectively, with patients older and younger than 60 years having equally good outcomes, according to Julie E. Chang, MD , of the Wisconsin Institute of Medical Research in Madison, and her colleagues.

VcR-CVAD is a moderate-intensity regimen with a favorable toxicity profile that allowed tolerability even in an older population, the investigators noted. “An important lesson illustrated by VcR-CVAD is that long-term remissions are achievable in some patients without intensive inductions or consolidation,” they wrote in Clinical Lymphoma, Myeloma & Leukemia .

The investigators previously reported that after a median follow-up of 42 months, the 3-year PFS and OS were 63% and 86%, respectively, and that these outcomes were comparable to those reported with more intensive regimens ( Br J Haematol. 2011 Oct;155[2]:190-7 ).

The current study reported longer follow-up from the same study. The cohort included 15 patients younger than 60 years and 15 who were 60 or older with previously untreated MCL, except for up to one cycle of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) or CHOP-like therapy. The patients were treated with VcR-CVAD induction chemotherapy for six (21-day) cycles. Those patients who had a partial response or better then underwent consolidation with rituximab 375 mg/m2 for 4 weekly doses, and maintenance with rituximab at the same dose every 12 weeks for up to 20 doses.

As noted, the ORR was 90%, including 77% CR/unconfirmed CR, 6-year PFS was 53%, and 6-year OS was 70%.

A univariate analysis showed a significant interaction between lactate dehydrogenase levels and age for PFS, and a trend, albeit not significant, toward an interaction with LDH levels and age for OS.

In multivariate analysis, worse Eastern Cooperative Oncology Group (ECOG) performance status at baseline showed a nonsignificant trend toward worse OS. In contrast, an increase of one in the number of extranodal disease sites was associated with better OS (relative risk 0.66, 95% confidence interval 0.01-0.66).

The investigators noted that the advent of new agents with activity against MCL and the use of prognostic information, such as minimal residual disease measurements, could help clinicians develop induction and maintenance strategies with better efficacy and lower toxicity than VcR-CVAD.

The study was supported by the National Institutes of Health, Millennium Pharmaceuticals, and the University of Wisconsin Forward Lymphoma Research Fund. Dr. Chang reported research funding from Genentech. One coauthor disclosed consulting work for Genentech and Millennium and research funding from Genentech.

SOURCE: Chang J et al. Clin Lymphoma Myeloma Leuk. 2018 Jan;18(1):e61-e67. doi: 10.1016/j.clml.2017.10.006 .