This is a 3 part phase 1, randomized, double-blind, placebo-controlled, study of the safety, tolerability, and pharmacokinetics of KVD824 following administration of single and multiple ascending oral doses; followed by a crossover food effect sub-study in healthy male volunteers.

Part A was a single-centre randomized, double blinded, placebo control to investigate the safety and tolerability of single ascending doses of KVD824 administered to healthy male volunteers.

Part B was a single centre, randomized, double blinded, placebo control to investigate the safety and tolerability of multiple ascending doses of KVD824 administered to healthy male volunteers.

Part C was a single-centre, open labelled to investigate the food effect.

Inclusion Criteria:

• Healthy male subjects between 18 and 55 years of age.
• Healthy subjects as determined by past medical history and as judged by the Chief Investigator / deputy.
• Male subject willing to wear a condom and whose partner of child bearing potential uses a highly effective method of contraception (e.g. partner use of intrauterine device (IUD)) or an effective method of contraception, i.e., established method of contraception + condom, if applicable (unless anatomically sterile or where abstaining from sexual intercourse is in line with the preferred and usual lifestyle of the subject) from first dose until 3 months after last dose of IMP. Men whose partners are already pregnant must continue to use a condom during the trial and for three months thereafter.
• Subject with a body mass index (BMI) of 18-32 kg/m2.
• Subject with no clinically significant history of previous allergy / sensitivity to KVD824 or any of the excipients contained within the Investigational Medicinal Product.
• Subject with no clinically significant abnormal serum biochemistry, haematology, clotting profiles, and urine examination values within 28 days before the first dose of Investigational Medicinal Product.
• Subject with a negative urinary drugs of abuse screen, determined within 28 days before the first dose of Investigational Medicinal Product (N.B. a positive result may be repeated at the Chief Investigator's discretion).
• Subject with negative human immunodeficiency virus (HIV) and hepatitis B surface antigen (Hep B) and hepatitis C virus antibody (Hep C) results.
• Subject with no clinically significant abnormalities in 12-lead electrocardiogram (QTcF ≤ 430 ms and PR interval 120-220 ms) determined within 28 days before first dose of Investigational Medicinal Product.
• Subject with no clinically significant abnormalities in vital signs (supine systolic (≤140 mmHg) and diastolic blood pressure (≤ 90 mmHg), pulse (≤ 100 bpm), oral temperature (≤ 37.5°C)) determined within 28 days before first dose of Investigational Medicinal Product.
• Subjects must not donate sperm from first dose until at least 3 months after last dose of Investigational Medicinal Product.
• Subjects without any special food restrictions that would hinder ability to consume gelatin (Part A and Part B placebo), or the high fat breakfast provided during study Part C; such as vegetarian, lactose intolerance, vegan, low-fat, low sodium, etc.
• Subjects with no known allergy or sensitivity to lactose and/or any additional excipients contained in Investigational Medicinal Product.
• Subject must be available to complete the study (including all follow up visits).
• Subject must satisfy the Chief Investigator / deputy about their fitness to participate in the study.
• Subject must provide written informed consent to participate in the study.

Exclusion Criteria:

• A clinically significant history of gastrointestinal disorder likely to influence Investigational Medicinal Product absorption.
• Use of prescription or non-prescription drugs, including vitamins, herbal and dietary supplements within 28 days or 5 half-lives (which ever is longer) prior to the first dose of Investigational Medicinal Product, unless in the opinion of the Chief Investigator the medication will not interfere with the study procedures or compromise subject safety.
• Evidence of renal, hepatic, central nervous system, respiratory, cardiovascular or metabolic dysfunction.
• Subjects with a history of clotting abnormalities.
• A clinically significant history of drug or alcohol abuse in the last 5 years.
• Users of nicotine products i.e., current smokers or ex-smokers who have smoked within the 6 months prior to dosing with the study medication or users of cigarette replacements (e.g., e-cigarettes, nicotine patches or gums).
• Inability to communicate well with Investigators (i.e., language problem, poor mental development or impaired cerebral function).
• Participation in a New Chemical Entity clinical study within the previous 3 months or a marketed drug clinical study within the 30 days before the first dose of Investigational Medicinal Product. (Washout period between studies is defined as the period of time elapsed between the last dose of the previous study and the first dose of the next study).
• Donation of 450 mL or more blood within the 3 months before the first dose of Investigational Medicinal Product.