A Combination of Melphalan, Prednisone, and 50 mg Thalidomide Treatment in Non-Transplant-Candidate Patients with Newly Diagnosed Multiple Myeloma

Background/Aims: The clinical efficacy and safety of a three-drug combination of melphalan, prednisone, and thalidomide were assessed in patients with multiple myeloma who were not candidates for high-dose therapy as a firstline treatment. Because the side effects of thalidomide at a dose of ${\geq}$ 100 mg daily can be a barrier to effective treatment for these patients, we evaluated the efficacy and safety of a reduced dose of thalidomide, 50 mg, for non-transplant candidates. Methods: Twenty-one patients were treated in 4-week cycles, receiving 4 mg/$m^{2}$ melphalan and 40 mg/$m^{2}$ prednisone on days 1-7 and 50 mg thalidomide daily. The primary efficacy outcome was the overall response rate. Aspirin (100 mg daily) was also provided as prophylactic treatment for thromboembolism. Results: The overall response rate was 57.1%; a complete response was seen in 23.8% of patients, a partial response in 33.3%, and stable disease in 9.5%. After a median follow-up time of 16.1 months, the median time to progression was 11.4 months (95% confidence interval, 2.1 to 20.6); the median overall survival was not reached. Grades 3 and 4 adverse events included infection (10%), peripheral neuropathy (5%), diarrhea (5%), thrombosis (10%), and loss of consciousness (10%). Two patients discontinued treatment due to loss of consciousness and neuropathy. Conclusions: Low-dose thalidomide (50 mg) plus melphalan and prednisone is an effective combination drug therapy option for newly diagnosed myeloma patients who are ineligible for high-dose chemotherapy.