[Efficacy of bortezomib combined dexamethasone in 24 patients with multiple myeloma]

Bortezomib, a potent and reversible proteasome inhibitor, induces apoptosis of myeloma cells, resulting in durable responses in patients with multiple myeloma (MM). This study was to explore the medical effects and side effects of bortezomib combined dexamethasone in treating newly diagnosed and relapsed or refractory MM, and evaluate the safety of this regimen in the patients with renal impairment.

Twenty-four MM patients were treated with bortezomib and dexamethasone in a 21-day cycle. The patients received a median of 3 cycles (range, 1-8 cycles) of the treatment. Response to bortezomib was evaluated according to the criteria of the European Group for Blood and Marrow Transplantation (EBMT); adverse events were graded according to the National Cancer Institute Common Toxicity Criteria.

During the follow-up with a median of 4 months, 19 (79.2%) patients responded to the treatment. The complete remission (CR) rate was significantly higher in the patients of light-chain type than in those of non-light-chain type (57.1% vs. 5.9%, P=0.014). The response rates of the patients with and without renal impairment were similar (100% vs. 70.6%, P=0.272), and the renal functions were ameliorated in the patients with renal impairment during chemotherapy. Grade III-IV adverse events, including leucocytopenia (8.3%), thrombocytopenia (33.3%), diarrhea (8.3%) and debility (4.2%), could be relieved by symptomatic treatment or delayed chemotherapy.

The combination of bortezomib and dexamethasone shows obvious effects on MM, especially in the patients with light-chain type. The adverse events can be tolerant in most patients, and this regimen is also safe in the patients with renal impairment.