2007

Mayo Clinic Briefings - Multiple Myeloma Trial Ends Early Because of Superior Results of Low-Dose Option

A Mayo Clinic Cancer Center and Eastern Cooperative Oncology Group clinical trial comparing 2 treatments for multiple myeloma was stopped early because preliminary data in April showed the low-dose option to be more effective and to have fewer adverse effects. The study enrolled 455 patients between 2004 and 2006 with newly diagnosed multiple myeloma, a cancer of the plasma cells in blood and bone marrow. Upon closure of the study, all patients were moved to the low-dose regime.

The 2 treatments being evaluated were both based on lenalidomide, a derivative of thalidomide, approved for use in combination therapy for multiple myeloma by the US Food and Drug Administration in 2006. The combination therapy under study consisted of lenalidomide coupled with either a low dose or a high dose of dexamethasone. The standard therapy for multiple myeloma has been lenalidomide with high-dose dexamethasone. Earlier data showed this standard dose to be effective in increasing life expectancy, but it also has toxic adverse effects.

In the trial, the new low-dose variant showed a 1-year survival rate of 96.5% and reduced toxicity, compared with a 1-year survival rate of 86% for patients on the standard high-dose combination with high toxicity. Researchers monitoring the data judged the difference between the 1-year survival rates to be among the most striking ever posted in a study of this kind. On this basis, they ended the trial early and switched all patients to the superior, low-dose regimen.