The addition of dexamethasone to bortezomib for the treatment of patients with relapsed multiple myeloma improves outcome but ongoing maintenance therapy has minimal benefit, a study published online in the American Journal of Hematology has shown.
It is common practice to combine dexamethasone with bortezomib in patients with multiple myeloma, but few prospective studies have studies this regimen. Therefore, researchers sought to assess the benefit of adding dexamethasone to bortezomib starting with cycle 1.
Researchers enrolled 100 patients with relapsed and/or refractory multiple myeloma. Patients received eight 21-day cycles of intravenous bortezomib 1.3mg/m2 on days 1, 4, 8, and 11, and three 35-day cycles with bortezomib 1.3mg/m2 given on days 1, 8, 15, and 22.
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Patients found to have stable disease or better then received maintenance bortezomib 1.3mg/m2 every 14 days until disease progression. Patients received dexamethasone 20mg for 2 days with each bortezomib dose.
Results showed that dexamethasone improved overall response rate by 20% (56% vs 36%; OR = 0.44; 95% CI: 0.24 – 0.80) and the median time to progression was significantly longer with dexamethasone (10.1 vs 5.1 months; HR = 0.50; 95% CI: 0.35 – 0.72; P = 0.0002), which the researchers attribute to the early use of dexamethasone. Results showed minimal benefit of the combination maintenance therapy.