Thalidomide Appears Effective in Early-Stage Myeloma

ROCHESTER, Minnesota—In a study of thalidomide (Thalomid) for early-stage multiple myeloma, 6 of 16 patients had a confirmed response—50% or greater reduction in serum and urine monoclonal (M) protein. S. Vincent Rajkumar, MD, and his colleagues at the Mayo Clinic reported the interim finding in Leukemia (8:1274-1276-2001).

When minor responses (25% to 49% decrease in M protein level) were included, the response rate was 69% (11 of 16 patients). Three other patients had stable disease, and only two progressed.

All 16 patients had asymptomatic smoldering or indolent multiple myeloma. Thalidomide 200 mg/d orally was given for 2 weeks. The dose was then increased as tolerated by 200 mg/d every 2 weeks to a maximum of 800 mg/d.

Dr. Rajkumar and his colleagues began the study in 1999. "We intended to conduct the study for 1 year to learn how a few newly diagnosed early-stage myeloma patients responded to thalidomide, but the encouraging results, coupled with patients wanting to stay on the drug, prompted us to continue the study and to publish our early findings," he said. He noted that several patients in the study are now in their third year of receiving thalidomide to control their myeloma.

Dr. Rajkumar does not currently recommend the routine use of thalidomide or any medication to treat myeloma at its very early smoldering or indolent stage because some patients can be stable for several months or years without therapy.

He recommends that randomized trials be conducted to determine if thalidomide can delay myeloma from progressing to the active, advanced stage.

The most common side effects in this study were rash (7 patients), fatigue (15), constipation (15), and mild paresthesia (13). Two patients had grade 3-4 somnolence, and one each had grade 3-4 syncope and neutropenia.