Single Ascending Dose Study of MSD-001 in Healthy Participants

Key Inclusion Criteria:

• Male or female healthy consented participants 18 to 55 years of age

• CYP2D6 phenotype established based on pharmacogenetic testing.

• Free from psychoactive drug use from 4 weeks before dosing and until the last followup visit.

Key Exclusion Criteria:

• Any current clinically relevant, or history of, acute or chronic diseases inclusiveof psychiatric disorders and relevant family history, which could interfere with theparticipant's safety during the trial, or expose them to undue risk, or which couldinterfere with the study objectives.

• Moderate to severe congestive heart failure, history of heart surgery, pulmonaryhypertension, systemic hypertension (i.e., systolic BP >139 mm hg, diastolic bloodpressure > 89 mm hg), pulse rate > 90 bpm, clinically significant ECG abnormality,QTc > 450 msec, myocardial infarction in the past year, or any other active orsevere cardiovascular condition.

• Clinically significant personal or familial history of epilepsy, seizures,convulsions, or other seizure disorder (excluding febrile seizures as a child),previous head trauma or other risk factor for seizure.

• Use of any psychedelic drug in the three months prior to planned dosing or theoccurrence of persistent psychological effects following the previous use ofpsychedelic drugs.

• Subject experiences severe anticipatory anxiety or is otherwise considered unfit forstudy.

• History of moderate or severe illicit substance abuse or dependence, or a positivetest result(s) for alcohol and/or drugs of abuse at screening or admission to theclinical unit.

• Subject has received a prior investigational intervention, has had a history ofrelevant hypersensitivity or allergic reactions, and has donated and/or received anyblood or blood products or experienced blood loss, that may interfere with theobjectives of the study.

• Subject has a significant negative life event (e.g. loss of a loved one) in the past 6 months.