This an open label study to assess the pharmacokinetics of CT1812 in normal healthy volunteers.

Open label study to assess PK in 36 older healthy volunteers. Subjects will be screened 35 days prior dose to determine eligibility. On day -1 subjects will be admitted to the clinical research unit and on day 1 will be randomized to receive one of the following doses: 150 mg BID, 150 mg QD or 300 mg QD in the fed state. Subjects will be confined in the Clinical Research Unit where they will continue to receive study drug and complete safety assessments, PK and CSF draws, until day 16 when they will be discharged.

Inclusion Criteria:

• Men and Women 50-80 years of age, inclusively
• In good health as determined by the Investigator with no clinically significant abnormalities
• Weight between 50.0 and 100.0 kg, inclusive at Screening
• No suicidal ideation
• No active depression
• Living independently at home or in a community setting
• Able to swallow CT1812 capsule or capsules
• Non-smoker with no history of using tobacco or any nicotine-containing products
• Subjects with negative serology for HIV, Hepatitis B, and C
• Negative results for drugs of abuse, cotinine, and alcohol
• Negative test results for COVID-19
• Willing to comply with Clinical Pharmacology Unit's COVID-19 policies

Exclusion Criteria:

• Any chronic medical condition which, in the opinion of the investigator, might pose a safety risk to the subject or interfere with study interpretation
• Subject with active or recent infection requiring antibiotic therapy
• Medical history of vasculitis or any autoimmune disease
• Any recent hospitalization
• Subjects living in a continuous care nursing facility
• Any contraindication to a lumbar puncture
• Subjects with self-reported history of major depression
• History of diabetes
• Intake of drugs or substances potentially involved in clinically significant induction or inhibition of CYP3A4 or P-gp mediated drug interactions with CT1812
• Intake of investigational drug prior to study drug administration on Day 1
• Participation in an investigational device study prior to study drug administration on Day 1
• Grapefruit, grapefruit juice, and Seville oranges/juice must be avoided within 14 days prior to dosing and throughout the course of the study
• Suspected or known drug or alcohol abuse,
• Excessive consumption of coffee, tea, cola, or other caffeinated beverages
• Loss or donation of blood; nation of bone marrow or peripheral stem cells; or donation of plasma
• Venous access considered inadequate; history or evidence of adverse symptoms associated with phlebotomy or blood donation
• Suspected or known allergy to any component of the study treatments
• Employee or family member of the Investigator, study site personnel, or Sponsor
• A subject with any condition that, in the opinion of the Investigator, makes the subject unsuitable for study participation will be excluded