This study is comprised of two parts. The purpose of the first part of this study is to evaluate the effects of a supratherapeutic dose of psilocybin on cardiac repolarization. The purpose of the second part of the study is to evaluate the effects of food on the pharmacokinetics of psilocybin.

Part one of this study will be a double-blind, single-dose, randomized, placebo-controlled, 4-treatment, 4-period, 12-sequence crossover design in 36 healthy volunteers (adult male and/or female subjects). Subjects will be randomly assigned to 1 of 12 different treatment administration sequences, whereby each sequence will include 3 double-blind treatments (therapeutic dose of psilocybin, supratherapeutic dose of psilocybin, and placebo) and 1 open-label positive control treatment (moxifloxacin).

Part two of this study will be an open-label, randomized, 2-period, 2-sequence crossover design in 24 healthy volunteers (adult male and/or female subjects). Each assigned treatment will be administered under fasting or fed conditions as a single dose on Day 1 of the respective study period.

Inclusion Criteria:

• Provision of signed and dated informed consent form (ICF)
• Stated willingness to comply with all study procedures and availability for the duration of the study
• Healthy adult male or female
• Aged at least 18 years but not older than 65 years, inclusive
• Body mass index (BMI) within 18.0 kg/m2 to 32.0 kg/m2 (for Part 1) or to 33.0 kg/m2 (for Part 2), inclusively

Exclusion Criteria:

• History of significant hypersensitivity to psilocybin or any related products (including excipients of the formulations) as well as severe hypersensitivity reactions (like angioedema) to any drugs
• Presence or history of significant gastrointestinal, liver or kidney disease, or surgery that may affect drug bioavailability
• History of significant cardiovascular, pulmonary, hematologic, neurological, psychiatric, endocrine, immunologic or dermatologic disease
• Showing suicidal ideation or behavior as per the Columbia Suicide Severity Rating Scale (C-SSRS) administered at screening
• Presence of out-of-range cardiac interval (PR < 110 msec, PR > 200 msec, QRS < 60 msec, QRS >110 msec and QTcF > 450 msec for males and > 470 for females) on the ECG at screening or other clinically significant ECG abnormalities, unless deemed non-significant by an Investigator
• History of risk factors for Torsades de Pointes (TdP), including unexplained syncope, known long QT syndrome, heart failure, myocardial infarction, angina, or clinically significant abnormal laboratory assessments including hypokalemia, hypercalcemia, or hypomagnesaemia
• Family history of long QT syndrome or Brugada syndrome
• Any clinically significant illness in the 28 days prior to the first study drug administration
• Intake of psilocybin or any other psychedelic (including 3,4-methylenedioxymethamphetamine [MDMA] and ketamine) in the 28 days prior to the first study drug administration
• Not suitable for participation in the study at the discretion of the Principal Investigator