Phase I trial of bortezomib in combination with rituximab-HyperCVAD alternating with rituximab, methotrexate and cytarabine for untreated aggressive mantle cell lymphoma.

Mantle cell lymphoma (MCL) outcomes have improved over the last two decades; however, late relapses occur. Bortezomib has shown single agent activity of 33% in relapsed MCL and has an additive/synergistic effect in vitro when combined with drugs currently used to treat MCL. We hypothesized that a combination of bortezomib with current intense non-transplant chemoimmunotherapy might prevent late relapses. The toxicity of bortezomib when combined with methotrexate and cytarabine is unknown. Patients aged 18-79 years with untreated aggressive MCL were treated with R-HyperCVAD (rituximab, cyclophosphamide, vincristine, doxorubicin, dexamethasone) alternating with rituximab-methotrexate/cytarabine (R-M/A). Bortezomib was added to the R-Hyper-CVAD combination as a fixed dose of 1·3 mg/m(2) IV on days 2 and 5 and was added to the R-M/A regimen after rituximab, in increasing doses of 0·7, 1, and 1·3 mg/m(2) in cohorts of three patients. Twenty patients were assessed for toxicity of the regimen. The principal toxicity was haematological and did not differ from that observed with a similar regimen without the bortezomib. In particular, there was no pulmonary or neurological dose-limiting toxicity, showing that bortezomib can be safely combined with R-HyperCVAD and R-M/A.

Ten-year follow-up after intense chemoimmunotherapy with Rituximab-HyperCVAD alternating with Rituximab-high dose methotrexate/cytarabine (R-MA) and without stem cell transplantation in patients with untreated aggressive mantle cell lymphoma.

Mantle cell lymphoma (MCL) has a poor overall survival after treatment with conventional chemotherapy. Intense chemoimmunotherapy without consolidation stem cell transplantation is a potential therapeutic option. We report on a prospective Phase II study with rituximab in combination with fractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone (R-Hyper-CVAD) alternating with rituximab in combination with high-dose methotrexate-cytarabine (R-MA) in untreated patients with diffuse and nodular MCL and their blastoid variants. Ninety-seven patients were treated, of whom 97% responded and 87% achieved a complete remission. At 10 years of follow up (median 8 years), the median overall survival (OS) for all patients had not been reached and the median time to failure (TTF) for all patients was 4.6 years, without a plateau in the curves. For the group of patients aged 65 years or younger, the median OS had not been reached and the median TTF was 5.9 years. Multivariate analysis revealed pre-treatment serum levels of beta(2) microglobulin, International Prognostic Index (IPI) score and mantle cell IPI (MIPI) score, as predictive of both OS and TTF. We conclude that intense chemoimmunotherapy without stem cell transplantation is effective for untreated aggressive MCL.