DISC-3405 (formerly MWTX-003) is an investigational anti-TMPRSS6 monoclonal antibody designed to increase hepcidin and suppress serum iron, with intended applications in polycythemia vera and other iron-overload conditions. Clinical development includes Phase 1 studies in healthy volunteers and planned patient studies. The product is not approved in any jurisdiction.
The FDA declined to approve Disc Medicine's bitopertin for erythropoietic protoporphyria on February 13, 2026, citing insufficient evidence linking biomarker reductions to clinical benefit. The company will pursue traditional approval using Phase 3 APOLLO trial data expected in Q4 2026.
Disc Medicine received a complete response letter from the FDA for bitopertin as a treatment for erythropoietic protoporphyria. The FDA acknowledged the drug lowers PPIX levels but requires evidence from the ongoing Phase 3 APOLLO study before approval.
| NCT ID | Title | Status | Phase |
|---|---|---|---|
| NCT07187973 |
A Phase 1b, Open-Label Study of DISC-3405 in Participants With Sickle Cell Disease (SCD) |
RECRUITING | PHASE1 |
| NCT06985147 |
A Phase 2, Open-Label Study of DISC-3405 in Participants With Polycythemia Vera (PV) |
RECRUITING | PHASE2 |
| NCT06050915 |
A Study of DISC-3405 in Healthy Volunteers |
COMPLETED | PHASE1 |
