New Drug Shows ‘Encouraging’ Outcomes for Pediatric Brain Tumor Treatment

Treatment with tovorafenib led to a 64% overall response rate in patients with recurrent or progressive pediatric low-grade glioma, study findings showed.

More than half of patients with recurrent or progressive pediatric low-grade glioma — the most common type of brain tumor in children — experienced their tumors shrink (known as overall response rate) when given tovorafenib (DAY101), according to findings from the ongoing phase 2 FIREFLY-1 trial.

Trial results, which were published by Day One Bio, the manufacturer of tovorafenib, showed that in 69 evaluable patients, the overall response rate was 64%, with 91% of patients experiencing a clinical benefit: three patients (4%) had a complete response, meaning that the were no signs left of cancer; 41 patients (59%) had a partial response, meaning that their tumors shrunk; and 19 patients (28%) had their disease stabilize.

These findings are promising to this patient population, which currently does not have a standard of care, explained Dr. Samuel Blackman, co-founder and chief medical officer at Day One.

“The responses we’ve observed in the FIREFLY-1 study with weekly monotherapy tovorafenib in children with recurrent or progressive low-grade gliomas are very encouraging,” Blackman said in a company-issued press release.

FIREFLY-1 included a total of 77 patients between the ages of 6 months and 25 years with recurrent or progressive pediatric low-grade glioma. On average, patients had three prior lines of therapy — with nearly 60% receiving at least one prior MAPK inhibitor —, and the average treatment duration with tovorafenib was 8.4 months. Fifty-nine patients (77%) were still on treatment at the time of the most recent data reporting.

The most common side effects seen with tovorafenib, which is administered once a week, were: change in hair color (75% of patients); increased creatine phosphokinase, which can indicate damage to the muscle tissue, heart or brain (64%); anemia (46%); fatigue (42%); and rash (42%).

“Based on the efficacy and safety profile of tovorafenib observed to date from the FIREFLY-1 trial population, we plan to submit a New Drug Application in the first half of this year that will include additional follow up from the full study population,” said Jeremy Bender, CEO of Day One, in the release.

When a pharmaceutical company submits a New Drug Application to the Food and Drug Administration (FDA), they are providing study data to the agency to prove that the treatment is safe and efficacious. If the FDA then files the New Drug Application, it will then review the research and determine if the drug should be approved.

“We look forward to continuing our discussions with regulatory authorities with the hope of bringing this therapy to children in need of new options as soon as possible,” Bender said.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.