GH1001 (GH001-PPD-203)

June 04, 2026: GH Research PLC (NASDAQ: GHRS) announced publication of full Phase 2a results for inhaled mebufotenin (GH001) in postpartum depression (PPD) and acceptance of two oral presentations at CINP 2026 (June 26–29, 2026; Glasgow).

GH001 in PPD (Phase 2a open-label, single-arm; n=10): The peer-reviewed article in The Journal of Clinical Psychiatry reports the primary endpoint was met with a mean MADRS reduction of 35.4 points from baseline to Day 8 (P<0.0001). All patients (10/10) achieved remission (MADRS ≤10) within two hours of dosing, sustained through Day 8. Maternal functioning improved (mean +34.1 points; +56% on the Barkin Index) at Day 8. Safety: no serious adverse events; treatment-emergent adverse events were mild/moderate; no treatment-emergent suicidal ideation/behavior. Breast milk analysis supports only a brief interruption of breastfeeding around dosing.

GH001 in TRD (Phase 2b GH001-TRD-201): Two CINP 2026 oral presentations will cover (1) efficacy with 6-month follow-up (June 27, 2026, 12:30–12:45 BST) and (2) safety/tolerability including open-label extension (June 28, 2026, 12:15–12:30 BST). The release also notes the Phase 2b primary endpoint was met with a MADRS reduction vs placebo of -15.5 points at Day 8 (P<0.0001).