Finally, following additional testing in mouse models, the researchers treated eight pediatric and young adult patients who had high-grade gliomas with avapritinib through a compassionate use program. Most of the patients had DMGs, and seven of the eight had PDGFRA alterations. All had previously undergone surgical biopsy or resection and radiation, and four had also received chemotherapy or other treatment approaches.
After being treated with avapritinib once daily for an average of four months, three of the patients demonstrated a radiographic response. The drug was also well tolerated. These three patients also survived roughly twice as long as those who didn’t respond to avapritinib, although their disease ultimately metastasized.
This early data suggests that avapritinib is generally safe and may trigger an initial clinical response in a small group of patients who have pediatric high-grade gliomas with PDGFRA amplification.
“Our research now provides the basis for a clinical trial for avapritinib in newly diagnosed pediatric patients,” says Filbin. “Our follow-up work focuses on genetic markers for personalized treatment and developing combination therapies with FDA-approved drugs to enhance efficacy.”