OBJECTIVETo compare the efficacy and safety of standard or reduced doses of bortezomib combined with adriamycin and dexamethasone (PAD) in patients with multiple myeloma (MM).

METHODSEighty-two newly diagnosed or refractory/relapsed patients received bortezomib [either 1.2-1.3 mg/m(2) (standard dose) or 1.0-1.1 mg/m(2) (reduced dose) on day 1, 4, 8 and 11], and adriamycin (10 mg/m(2)) plus dexamethasone (40 mg/m(2)) on day 1-4 at 3-week intervals for 1 to 6 courses. The International Myeloma Working Group Criteria were used to evaluate the response. Adverse events were graded according to the National Cancer Institute Common Toxicity Criteria (Version 3.0).

RESULTSTwo courses of standard dose of PAD resulted in a similar response rate of partial and very good partial complete remissions (PR) compared with reduced dose (80.0% vs 80.8%, P=0.728). Grade III- Ⅳ neutropenia and thrombocytopenia were higher with standard dose than that with reduced doses of PAD (21.1% vs11.1%, P=0.270; 10.5% vs 6.3%, P=0.619, respectively). Grade III-Ⅳ bortezomib-induced peripheral neuropathy, herpes zoster, fatigue or abdominal distention were significantly higher with standard dose than that with reduced dose of PAD (15.8% vs 1.6%, P=0.037; 26.3% vs 6.3%, P=0.028; 36.8% vs 14.3%, P=0.046; 15.8% vs 1.6%, P=0.037, respectively).

CONCLUSIONReduced dose of PAD appears to result in a similar overall response rate, but a better tolerance and safety compared with standard dose.