FDA Approves First Drug Developed for Children with Rare Brain Tumor
Last week, the U.S. Food and Drug Administration approved Afinitor Disperz—pediatric doses of everolimus (Afinitor) tablets—to treat a rare brain tumor called subependymal giant cell astrocytoma (SEGA). Afinitor Disperz is the first approved form and dose of a drug developed to treat pediatric tumors.
Afinitor Disperz dissolves easily in a small amount of water, making the treatment easy to administer to patients who are unable to swallow whole tablets. It is also available in smaller doses than everolimus, the adult form of the drug.
Afinitor Disperz is recommended to treat patients 1 year of age and older who have tuberous sclerosis complex (TSC) and are diagnosed with SEGA but who are ineligible for surgery. Prior to the approval of this new dosage form, everolimus was recommended only for patients 3 years of age and older.
TSC is a rare genetic disease that causes tumors to grow in the brain and other vital organs. SEGA is a slow-growing tumor that can cause life-threatening complications by blocking the flow of fluid in the brain. These tumors occur in 6 to 9 percent of TSC patients, generally children and young adults.
Everolimus blocks the uncontrolled activity of a protein called mTOR kinase, which plays a critical role in the development and growth of SEGA tumors occurring in patients with TSC.
Everolimus was granted accelerated approval in 2010 to treat SEGA in patients with TSC.
Everolimus and Afinitor Disperz remain under accelerated approval for the treatment of SEGA in patients with TSC. Everolimus’ manufacturer, Novartis, updated safety and efficacy data from the single-arm study of 28 pediatric and adult patients used to support the drug’s accelerated approval in 2010 for the treatment of SEGA in patients with TSC.
In a more recent study involving 117 pediatric and adult patients who were randomly assigned to take everolimus or a placebo daily, 35 percent of patients treated with everolimus experienced tumor shrinkage compared with none who were treated with placebo. The most common side effects observed in patients with SEGA were mouth ulcers and respiratory tract infections.
Studies continue to evaluate the long-term safety and effectiveness of everolimus and Afinitor Disperz in pediatric and adult patients with SEGA. Afinitor Disperz is classified as an orphan drug because it is intended to treat a rare disease or condition. Afinitor Disperz’s application was granted priority review, which the FDA completed in 6 months.