Brineura approval for CLN2 disease (2017)
BioMarin won FDA approval for Brineura (cerliponase alfa), the first treatment for neuronal ceroid lipofuscinosis type 2 (CLN2 disease), a fatal neurodegenerative condition that strikes children around age two and causes seizures, loss of motor function, and death by early adolescence. The approval was based on a study of just 24 patients—even smaller than relutrigine's EMBOLD trial.
Brineura was approved based on a single-arm study with a historical comparator, demonstrating the FDA's willingness to accept unconventional trial designs for devastating pediatric diseases. BioMarin received a Priority Review Voucher it sold to Gilead for $125 million.
The approval established precedent that small trials in ultra-rare pediatric diseases can support approval when the unmet need is severe and the treatment effect is clear.
Relutrigine's EMBOLD trial enrolled 51 patients—small by conventional standards but larger than Brineura's pivotal study. The Brineura precedent suggests the FDA is prepared to approve based on limited patient numbers when the disease is severe, no alternatives exist, and the clinical signal is strong.
