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

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.