Disc Medicine says bitopertin met Phase 3 goals for rare light-sensitivity disease

Disc Medicine said its oral drug bitopertin met all of its main and secondary objectives in a Phase 3 trial for erythropoietic porphyria, or EPP, a rare disease that causes painful reactions to bright light.

After six months, the drug lowered blood levels of protoporphyrin IX, or PPIX, by about 46%, compared with just over a 4% reduction for placebo recipients, Disc reported. The company also reported a 12.2-hour increase, relative to placebo, in pain-free time in light during the sixth month. Disc said dizziness was the most common treatment-related side effect.

The FDA rejected Disc’s request for accelerated approval in February, saying prior trials did not clearly show that lower PPIX levels meant patients could tolerate more sunlight, BioPharma Dive reported. The FDA letter said traditional approval could be possible if bitopertin succeeded in a Phase 3 trial. Disc plans to re-engage regulators and resubmit an application by the end of the year. The company said the treatment could launch in 2027.