Clinical Study of GH001 in Depression

Inclusion Criteria: * Has a body mass index (BMI) in the range of 18.5 and 35.0 kg/m2 (inclusive); * Meets the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) diagnostic criteria for single-episode major depressive disorder (MDD) or recurrent MDD, without psychotic features confirmed by the Mini-International Neuropsychiatric Interview (MINI); * Treatment-Resistant Depression as evaluated by the Antidepressant Treatment History Form - Short Form (ATHF-SF); * Has outpatient status at screening and enrolment visits; Exclusion Criteria: * Has a current or prior diagnosis of a psychiatric comorbidity that renders the patient unsuitable for the study according to a study psychiatrist or registered psychologist; * Has received any investigational medication within the last 1 month; * Has a current medically significant condition (e.g., severe infection) or has a history of a medically significant condition (e.g., medical history of seizure, uncontrolled hypertension, uncontrolled diabetes, severe cardiovascular disease, hepatic or renal failure, etc.) that renders the patient unsuitable for the study according to the medical supervisor's judgment; * Takes any medication or other substance that renders the patient unsuitable for the study according to the medical supervisor's judgment; * Has a clinically significant abnormality in physical examination, vital signs, ECG, or clinical laboratory parameters, which renders the patient unsuitable for the study according to the medical supervisor's judgment;