Targeted therapy for brain cancer shows efficacy

In patients diagnosed with grade 2 IDH-mutant glioma, treatment with investigative vorasidenib has significantly improved progression-free survival.

The findings were published on June 5, 2023 in the NEJM/New England Journal of Medicine, and they were reported on the same day at the annual meeting of the American Society of Clinical Oncology.

Senior author Timothy Cloughesy, MD, professor of neuro-oncology at the David Geffen School of Medicine at UCLA in Los Angeles, said that the availability of a treatment enabling patients to go for longer periods of time between chemotherapy and radiation treatments could have a major effect on treatment planning for the disease. “We’re always concerned about the delayed effects of radiation,” he said. “Having the ability to hold off on getting radiation therapy to the brain with an effective therapy is really critical and very meaningful to this population of patients.”

The authors noted that the phase 3 trial was the first to analyze a targeted therapy drug specifically developed to treat brain cancer.

The investigators randomized 331 subjects with residual or recurrent grade 2 IDH-mutant glioma who had undergone no prior treatment except surgery to receive either oral vorasidenib (n=168, 40 mg once daily) or matched placebo (n=163) in 28-day cycles.

The primary endpoint was progression-free survival.

Placebo subjects were allowed crossover to vorasidenib on confirmation of imaging-based disease progression.

At a median follow-up of 14.2 months, 226 subjects (68.3%) were continuing to receive vorasidenib or placebo.

Median progression-free survival was significantly higher in the vorasidenib group compared with the placebo group (27.7 months vs. 11.1 months; P<0.001).

As of September 2022, 30 months after the study began, 72% of patients in the vorasidenib group continued to take the drug, and their disease had not progressed.

Time to the next anti-cancer intervention was statistically significantly improved in the vorasidenib group compared with the placebo group (P<0.001).

“This is the first targeted treatment that shows unequivocal efficacy in this population and is precedent-setting for this disease,” Cloughesy said.