Mayo Clinic study finds no survival benefit from longer multiple myeloma maintenance therapy

Rochester, Minn. — A major U.S.-led cooperative group clinical trial coordinated by Mayo Clinic researchers has found that extending maintenance therapy with lenalidomide beyond two years does not improve overall survival for patients with standard-risk multiple myeloma. The results address a long-standing question in cancer care: when does “continuous” treatment stop paying off?

The study compared two strategies after initial therapy: continuing lenalidomide maintenance beyond a two-year mark versus stopping treatment at two years. Researchers reported no overall survival advantage for the longer-duration approach, suggesting that, for the trial’s specific patient population, indefinite therapy may not translate into better long-term outcomes.

In multiple myeloma, maintenance treatment aims to suppress residual disease and delay relapse. However, as therapeutic regimens have improved over the past two decades, some patients now achieve sustained control for extended periods. This changing landscape increases the importance of determining not only whether a therapy works, but also how long it should be used to maximize benefit while limiting harm.

Mayo Clinic hematologist Shaji Kumar, M.D., emphasized that “longer” is not automatically “better,” particularly when treatment options become more effective. He noted that clinical decision-making should increasingly incorporate duration—an often overlooked variable that can influence quality of life, toxicity exposure, and health care costs.

Another trial leader, S. Vincent Rajkumar, M.D., highlighted the potential patient impact. If maintenance therapy can be safely discontinued after a defined interval, clinicians may reduce treatment burden and support shared decision-making based on evidence rather than convention.

The research applies specifically to patients with standard-risk multiple myeloma who did not receive an upfront stem cell transplant. That detail matters because disease biology and treatment intensity differ across risk categories and treatment pathways, potentially changing the balance between benefit and ongoing therapy.

The trial was supported through the ECOG-ACRIN Cancer Research Group and involved backing from the U.S. National Institutes of Health’s National Cancer Institute via the National Clinical Trials Network. Additional support came from Amgen, reflecting the collaborative, large-scale nature of the investigation.

Researchers say additional studies are underway to refine maintenance duration for high-risk disease and to test whether measurable residual disease (MRD) measurements could enable more individualized treatment stopping points.

The publication, featured in The New England Journal of Medicine, underscores a broader principle for oncology trials: adding new therapies remains crucial, but trials should also clarify when treatment can be responsibly paused or ended.