The FDA has approved vorasidenib, the first targeted drug for people with Grade 2 diffuse glioma that carries an IDH1 or IDH2 mutation. This marks an important advance for a slow-growing but incurable brain cancer.
About 3,500 Americans are diagnosed with this type of tumor each year. Most cases (70–80%) have an IDH1 mutation. Patients usually live 10–12 years, but the disease can eventually become more aggressive. Before this approval, no treatments were designed specifically for IDH-mutant low-grade glioma. Care often involved surgery and chemotherapy such as temozolomide or PCV.
Vorasidenib is an oral medicine that blocks mutant IDH1 and IDH2 enzymes, lowering levels of a cancer-promoting molecule called 2-HG. Its approval is based on the INDIGO trial, which enrolled 331 patients who had surgery.
The drug significantly slowed tumor growth. Median progression-free survival was 27.7 months with vorasidenib versus 11.1 months with placebo. It also postponed the need for further treatments like radiation or chemotherapy; many patients taking the drug still had not needed more therapy, while the placebo group reached this point at 17.8 months.