In 2008, the U.S. Food and Drug Administration (FDA) approved a new indication for Cytogenomics’ lenalidomide, that is, combined treatment with dexamethasone (Dexamethasone) for patients who have received at least one therapy in patients with multiple myeloma. Lenalidomide is an immunomodulator. In clinical trials, most side effects and serious side effects were more frequent with lenalidomide plus dexamethasone than with dexamethasone alone. In addition, because lenalidomide is a derivative of thalidomide, it still has the potential to cause birth defects, and clinical prescription must strictly follow a proprietary special procedure.
In a trial of lenalidomide combined with dexamethasone in the treatment of relapsed or refractory multiple myeloma, 351 patients who had received at least one original anti-myeloma treatment were randomly divided into 2 groups. The 176 people in the group took 25 mg of lenalidomide orally every day from days 1 to 21, and the 175 people in the control group took placebo, with a cycle of 28 days. In addition, all patients took 40 mg of dexamethasone orally daily on days 1-4, 9-12, and 17-20 of the first 4 cycles, and only on days 1-4 after the first 4 cycles. If a patient develops disease progression or intolerable toxicity, the trial will be terminated. The original trial termination point was the time point of disease progression.
Results: The time point of disease progression in patients taking lenalidomide and dexamethasone (lenalidomide group) was significantly later than that in the placebo and dexamethasone group (placebo group) (mean was 11.3 months vs. 4.7 months; P<0.001). 106 patients in the lenalidomide group showed complete or partial response (60.2%), and 42 patients in the placebo group (24.0%, P<0.001). The complete response rates were 15.9% and 3.4% (P<0.001) respectively. Overall survival was significantly improved in the lenalidomide group (hazard ratio of death, 0.66; P=0.03). Grade 3 or 4 side effects occurred in greater than 10% of patients in the lenalidomide group, including neutropenia (29.5%, vs. 2.3% in the placebo group), thrombocytopenia (11.4% vs. 5.7%), and venous thrombosis. (11.4% vs. 4.6%).
Conclusion: Lenalidomide combined with dexamethasone is more effective than high-dose dexamethasone alone in the treatment of relapsed or refractory multiple myeloma