How to determine bortezomib-based regimen for elderly patients with multiple myeloma: PAD versus CBd, an observational study.

ABSTRACT

BACKGROUND: This was an open-label, observational, prospective assessment. We conducted an analysis of the impact of bortezomib-based therapy (PAD bortezomib, doxorubicin, high-dose dexamethasone vs. CBd cyclophosphamide bortezomib, low-dose dexamethasone) on the survival rates and adverse events in elderly patients with newly diagnosed multiple myeloma (MM). METHODS: Out of 303 patients, 128 received the PAD regimen and the other 175 patients received the CBd induction therapy (age 65-89 years). Baseline patient characteristics between the two cohorts were balanced in age (P = 0.69), international staging system (ISS) prognostic stages (P = 0.90), serum calcium (P = 0.70), and serum creatinine (P = 0.52). RESULTS: Overall response (OS) after the induction chemotherapy was achieved in 214 of 303 patients (70.6 %), with no significant differences observed between the two treatment groups (71.9 vs. 69.7 %, P = 0.68). Patients with ISS stage 2 reached the same 5-year OS advantages compared to patients with ISS stage 1, because they received bortezomib-based PAD or CBd treatments. Patients receiving CBd protocol gained similar satisfactory progression-free survival (PFS) results when compared to the PAD regimen group PFS at 5 years reached 58.2 versus 58.9 % (P = 0.85). Five-year OS in the CBd arm had significant advantages compared to the PAD group, 79.9 versus 49.9 % (P < 0.05). The overall safety profiles showed that 26 of 128 (20.3 %) patients died in the PAD arm, while 13 of 175 patients died (7.4 %) in the CBd group (P < 0.01). Similarly, the PAD arm had a higher serious infection rate than that of the CBd arm (39.2 vs. 13.1 %, P < 0.01). CONCLUSIONS: Bortezomib benefits elderly patients with newly diagnosed MM; they achieve satisfactory treatment responses and survival advantages. Further, patients treated with CBd have superior treatment advantages, with a predictable safety profile, when compared to the PAD regimen.