Phase III trial of bortezomib, cyclophosphamide and dexamethasone (VCD) versus bortezomib, doxorubicin and dexamethasone (PAd) in newly diagnosed myeloma

Abstract

We aimed at demonstrating non-inferiority of bortezomib/cyclophosphamide/dexamethasone (VCD) compared to bortezomib/doxorubicin/dexamethasone (PAd) induction therapy with respect to very good partial response rates or better (≥VGPR) in 504 newly diagnosed, transplant-eligible multiple myeloma patients. VCD was found to be non-inferior to PAd with respect to ≥VGPR rates (37.0 versus 34.3%, P=0.001). The rates of progressive disease (PD) were 0.4% (VCD) versus 4.8% (PAd; P=0.003). In the PAd arm, 11 of 12 patients with PD had either renal impairment (creatinine ≥2 mg/dl) at diagnosis or the cytogenetic abnormality gain 1q21, whereas no PD was observed in these subgroups in the VCD arm. Leukocytopenia/neutropenia (≥3°) occurred more frequently in the VCD arm (35.2% versus 11.3%, P<0.001). Neuropathy rates (≥2°) were higher in the PAd group (14.9 versus 8.4%, P=0.03). Serious adverse events, both overall and those related to thromboembolic events, were higher in the PAd group (32.7 versus 24.0%, P=0.04 and 2.8 versus 0.4%, P=0.04). Stem cell collection was not impeded by VCD. VCD is as effective as PAd in terms of achieving ≥VGPR rates with fewer PD and has a favorable toxicity profile. Therefore, VCD is preferable to PAd as induction therapy.