Summary of Conference Call on GH Research's Phase IIb Trial Results Company and Industry - **Company**: GH Research - **Industry**: Biotechnology, specifically focusing on treatments for treatment-resistant depression (TRD) Core Points and Arguments 1. **Trial Overview**: The Phase IIb trial involved a double-blind placebo-controlled design with an open-label extension to assess the safety and efficacy of GA001 in patients with treatment-resistant depression [1][3] 2. **Primary Endpoint**: The primary endpoint was the mean change in the Montgomery-Åsberg Depression Rating Scale (MADRS) between GA001 and placebo at day eight, showing a statistically significant reduction of -15.5 points for GA001 compared to placebo [13][39] 3. **Efficacy Timeline**: GA001 demonstrated ultra-rapid efficacy, with significant reductions in MADRS scores observed as early as two hours post-treatment [13][39] 4. **Remission Rates**: The remission rate for GA001 was reported at 57.5% on day eight, compared to 0% for placebo, indicating a strong clinical relevance of the treatment [15][21] 5. **Safety Profile**: GA001 was well tolerated, with no serious adverse events reported. Common mild to moderate treatment-emergent adverse events included nausea and headache [22][39] 6. **Open Label Extension Results**: In the ongoing open-label extension, 77.8% of patients were in remission at six months, with 81.5% being responders, indicating sustained efficacy over time [32][40] 7. **Dosing Regimen**: Patients received individualized dosing regimens, with the majority requiring two doses on the same day. The psychoactive effects lasted approximately 15 minutes [12][57] 8. **Comparison with Existing Treatments**: GA001 showed a significant advantage over existing treatments like Spravato, with fewer required treatment visits and higher remission rates [33][38] Additional Important Content 1. **Patient Characteristics**: The trial enrolled 40 patients in the GA001 arm and 41 in the placebo arm, with a mean baseline MADRS score of 29, indicating moderate to severe depression [10][11] 2. **Retreatment Criteria**: Patients were retreated based on severity of depression, with specific MADRS cutoffs guiding the decision [5][6] 3. **Quality of Life Measures**: GA001 led to a significant increase of 20.6 points on the Quality of Life Satisfaction and Enjoyment Questionnaire (QLSF), correlating with the reduction in MADRS scores [20][34] 4. **Regulatory Engagement**: The company is preparing to engage with the FDA to resolve a clinical hold and discuss the pivotal program for GA001 [48][51] 5. **Discharge Criteria**: Patients were assessed for sedation and dissociation before discharge, with 97.5% being ready within one hour post-treatment [23][78] 6. **Hallucination Reports**: Only one patient reported a brief visual hallucination during the psychoactive phase, indicating a low incidence of such effects [78] This summary encapsulates the key findings and discussions from the conference call regarding GH Research's Phase IIb trial results for GA001, highlighting its potential as a treatment for treatment-resistant depression.