Researchers have reported encouraging results from a major international clinical trial involving patients with relapsed or treatment-resistant multiple myeloma, a serious blood cancer.

The study focused on the experimental drug mezigdomide, which was administered in combination with the established therapies carfilzomib and dexamethasone.

According to findings published in the New England Journal of Medicine, the combination significantly prolonged disease control compared with the current standard treatment regimen.

The Phase III SUCCESSOR-2 trial enrolled 479 patients whose multiple myeloma had either returned after previous treatment or become resistant to therapy. Many participants had already undergone several lines of treatment and had limited remaining therapeutic options.

The results were highly promising. Patients receiving the new three-drug combination achieved a median progression-free survival of 18 months, compared with 8.3 months in the standard-treatment group. In other words, the new regimen more than doubled the period during which the disease remained under control.

In addition, the therapy reduced the risk of disease progression or death by 52%. More than 80% of patients responded to treatment, and approximately one in four achieved levels of disease that were undetectable using modern diagnostic methods.

Mezigdomide belongs to a new generation of immunomodulatory drugs. It enhances the immune system’s ability to recognize and destroy myeloma cells. Another notable advantage is that the drug is administered orally in tablet form, making treatment more convenient than some currently available intravenous therapies.

Side effects were more common than with standard treatment, primarily due to reduced levels of certain blood cells and an increased risk of infections. However, the researchers noted that these complications were generally manageable and responded well to treatment.

According to the study authors, the findings could lead to a new standard of care for patients with relapsed multiple myeloma, particularly if longer follow-up confirms a survival benefit.