A phase 2 trial of VRD induction for transplant-eligible Japanese patients with newly diagnosed multiple myeloma

This single-arm phase 2 trial investigated the efficacy and safety of bortezomib-lenalidomide-dexamethasone (VRD) induction for transplant-eligible Japanese patients with newly diagnosed multiple myeloma. Treatment consisted of four cycles of VRD (bortezomib 1.3 mg/m², s.c., days 1, 4, 8, 11; lenalidomide 25 mg/body/day, days 1-14; dexamethasone 40 mg/day, p.o., days 1, 4, 8, 11), stem cell mobilization with low-dose cyclophosphamide (1 g/m², day 1) and bortezomib (1.3 mg/m², days 4, 7), and high-dose therapy with melphalan supported by autologous peripheral blood stem cell transplantation. Primary endpoints were post-induction complete response (CR) and near CR (nCR) rates. Seven of the 23 enrolled patients discontinued induction therapy, including 5 due to grade 3 or 4 non-hematologic toxicities. Moreover, 8 of the 16 patients who completed induction therapy required dose reduction. Post-induction CR and nCR rates in the intent-to-treat population were 17.4% and 8.7%, respectively. Comparison of pre- and post-induction quality of life (QoL) indicators, such as QLQ-C30 and QLQ-MY20, revealed that VRD induction does not adversely affect QoL in patients who tolerate the treatment. Collectively, these findings indicate a need to optimize the dose and schedule of VRD induction, at least in Japanese patients.