Combination brentuximab vedotin and nivolumab showed manageable safety and high activity in patients with relapsed/refractory primary mediastinal B-cell lymphoma (PMBL), according to results from a phase 2 trial.
“We evaluated whether the combination of nivolumab and [brentuximab vedotin] was safe and synergistically effective in patients with [relapsed/refractory] PMBL,” Pier Luigi Zinzani, MD, PhD, of the University of Bologna (Italy), and colleagues wrote in the.
The CheckMate 436 study is a multicenter, open-label, phase 1-2 study that included patients with relapsed/refractory disease who had previously received autologous stem cell transplantation (ASCT) or had two or more previous chemotherapy regimens for those ineligible for ASCT.
The phase 2 component evaluated the safety and efficacy of the two-drug combo in an expansion cohort of 30 patients. Study participants received intravenous brentuximab vedotin at 1.8 mg/kg and nivolumab at 240 mg every 3 weeks until cancer progression or intolerable adverse effects.
The primary outcomes were the investigator-evaluated objective response rate and safety. Secondary outcomes included progression-free survival, complete remission rate, overall duration of response, among other measures.
After analysis, the researchers reported that 53% of patients had grade 3 or 4 treatment-related toxicities following a median of five treatment cycles. The most common treatment-related toxicities were neutropenia (30%) and peripheral neuropathy (27%).
Five patients died during the study follow-up, four because of disease progression and one as a result of sepsis that was not considered related to treatment.
At a median follow-up of 11.1 months, the objective response rate was 73% in study participants, including 11 patients (37%) who achieved a complete response and 11 patients (37%) who had a partial response. An additional three patients had stable disease.
The median progression-free survival, duration of response, and overall survival were not reached in this study.
“The combination of nivolumab and [brentuximab vedotin] may be synergistic and is highly active in patients with [relapsed/refractory] PMBL, serving as a potential bridge to other consolidative therapies of curative intent,” the researchers wrote.
The study was funded by Bristol-Myers Squibb and Seattle Genetics. The authors reported financial affiliations with the study sponsors and several other companies.
SOURCE: Zinzani PL et al. J Clin Oncol. 2019 Aug 9. .