Extended myeloma maintenance therapy shows no additional survival benefit

A major national cooperative group clinical trial led by Mayo Clinic researchers found that continuing maintenance therapy with lenalidomide beyond two years after initial treatment for standard-risk multiple myeloma did not improve overall survival compared with stopping treatment after two years. The findings, published in The New England Journal of Medicine, may help physicians and patients make more informed decisions about the duration of maintenance therapy.

"Longer treatment is often assumed to be better, but that's not always the case," says Shaji Kumar, M.D., a Mayo Clinic hematologist, the study's primary investigator. "As therapies become more effective, it's increasingly important to determine not only which treatments work, but also how long patients need them." The researchers say the findings may reduce treatment burden and lower the costs associated with years of ongoing therapy for many patients.

"Knowing that maintenance therapy can safely end after a defined period may help reduce the demands of long-term treatment for patients," says S. Vincent Rajkumar, M.D., a hematologist at Mayo Clinic and chair of the ECOG-ACRIN Cancer Research Group's Myeloma Committee which spearheaded the trial. "These findings support informed, shared decision-making between physicians and patients."

New treatments for multiple myeloma over the past two decades have improved survival, and some patients now experience long-term disease control. The study applies specifically to patients with standard-risk multiple myeloma who did not receive an upfront stem cell transplant. Additional studies are underway to determine the optimal duration of maintenance therapy for patients with high-risk disease and to explore whether treatment duration can be tailored using measurable residual disease testing.

"This study reminds us that clinical trials shouldn't only focus on adding new therapies," Dr. Kumar says. "They should also help us understand when treatment can safely stop."

The trial was designed and conducted by the ECOG-ACRIN Cancer Research Group with support from the U.S. National Institutes of Health's National Cancer Institute, through its National Clinical Trials Network. Amgen provided additional support.