Drug treatment rather than observation may delay disease progression and extend survival in persons with high-risk smoldering multiple myeloma, according to recent study results.
The standard of care for patients with smoldering multiple myeloma (early disease without symptoms) is observation until symptoms develop. However, this approach does not identify high-risk patients who may benefit from early intervention, as pointed out by Jesús-F San Miguel, MD, PhD, of the hematology department at University Hospital of Salamanca in Salamanca, Spain, and colleagues in The New England Journal of Medicine (2013;369:438-447).
San Miguel’s team randomized 119 patients with high-risk smoldering myeloma to treatment or to observation in order to evaluate time to progression to symptomatic disease as well as overall survival, response rate, and safety. The treatment group was administered an induction regimen of lenalidomide 25 mg/day for 21 days, plus dexamethasone 20 mg/day on days 1 to 4 and days 12 to 15, at 4-week intervals for nine cycles. These patients then received a maintenance regimen consisting of lenalidomide 10 mg/day on the first 21 days of each 28-day cycle for 2 years.
After a median follow-up of 40 months, the median time to progression was significantly longer in the treatment group than in the observation group: Median time to progression had not been reached in the treatment group, and was 21 months in the observation group. The treatment group also had a higher 3-year survival rate (94% vs 80%).
Most members of the treatment group achieved a partial response or better after the induction phase (79%) and during the maintenance phase (90%). Toxic effects were mainly grade 2 or lower.
San Miguel and coauthors concluded that early treatment for persons with high-risk smoldering myeloma delays progression to active disease and increases overall survival.