The purpose of this clinical trial is to evaluate the safety and tolerability of LH-001 when administered as an oral, single or multiple dose(s) at ascending dose levels in healthy participants.

This is a first-in-human, randomized, double-blinded, placebo-controlled study. This study consists of two parts: (1) single ascending doses in 4 cohorts (SAD) and (2) 14-day multiple ascending doses in 3 cohorts (MAD). Cohorts may be added or removed if needed due to safety considerations or deviations of actual PK parameters from predicted values.

The SAD study consists of a screening visit, a 2-day inpatient stay (Day 1-2), a return visit for safety assessments on Day 3, Day 4, and Day 8.

The MAD study consists of a screening visit, a 2-day inpatient stay (Day 1-2), daily return for dosing and safety assessments (Day 3-13), a 2-day inpatient stay (Day 14-15), and a follow-up by phone (Day 21).

Inclusion Criteria:

• Healthy males or females aged 18-60 years at the time of consent
• Must provide written informed consent
• Physically and mentally able and willing to participate in the safety and other assessments including staying overnight
• BMI 18-29.9 kg/m2
• Sexually active male participants, sexually active female participants of childbearing potential, and their sexual partners are to adhere to the contraception requirements. These requirements include utilizing highly effective birth control (including hormonal methods, intrauterine devices, and/or barrier methods) from the screening phase through the completion of the last study follow-up. Note, the barrier method may not be used as a standalone method and must be combined with an additional approved method.
• Participants taking non-prescribed medication must cease taking the medication for at least 48 hours prior to dosing of LH-001.

Exclusion Criteria:

• Taking any prescription medications outlined in the prohibited/conditional drug list (see Section 6.8.1)
• History or presence of gastrointestinal, renal, or hepatic disease or any other condition known to interfere with absorption, distribution, metabolism, or excretion of drugs
• History or presence of major disorder of any other major organ system (cardiovascular, respiratory, central nervous system, or endocrine system)
• History of cancer within 5 years of consent (exceptions are squamous and basal cell carcinomas of the skin)
• Any clinically important illness, medical/surgical procedure, or trauma within 4 weeks prior to dosing.
• History or presence of alcohol or substance abuse
• History of chronic or current use of recreational or illicit drugs
• History of, or treatment for, major psychiatric illness
• History of, or treatment for, seizures or epilepsy
• Pregnant or breast-feeding females
• History of, or treatment for, an autoimmune disease (e.g., Rheumatoid Arthritis, Multiple Sclerosis, Myasthenia Gravis, etc.)
• History of asplenia, hyposplenia, or splenectomy
• History or presence of drug hypersensitivity
• Poor venous access
• Receipt of investigational therapy within 4 months prior to screening
• Current or previous use of systemic corticosteroids or other systemic immunosuppressive agents 4 weeks prior to dosing
• Current or previous use of NMDA antagonists 4 weeks prior to dosing
• Clinically significant findings in the opinion of the investigator in the laboratory, physical examination, or vital sign assessments
• Evidence of active Hepatitis B, Hepatitis C, or HIV on laboratory testing
• Any clinically significant ECG abnormality in the opinion of the investigator
• Plasma or blood donation within the last 4 weeks
• Positive drug or alcohol screen
• Any contraindication to or unable to tolerate a LP, for those who consented to the procedure, including the use of anti-coagulant medications. Daily administration of 81 mg aspirin will be allowed
• Any concurrent condition that, in the opinion of the investigator, would interfere with the evaluation of LH-001
• Participants who answer "Yes" on the C-SSRS Suicidal Ideation Item 4 (Active Suicidal Ideation with Some Intent to Act, Without Specific Plan) and whose most recent episode meeting criteria for this C-SSRS Item 4 occurred within the last 6 months, OR Subjects who answer "Yes" on the C-SSRS Suicidal Ideation Item 5 (Active Suicidal Ideation with Specific Plan and Intent) and whose most recent episode meeting criteria for this CSSRS Item 5 occurred within the last 6 months OR Subjects who answer "Yes" on any of the 5 C-SSRS Suicidal Behavior Items (actual attempt, interrupted attempt, aborted attempt, preparatory acts, or behavior) and whose most recent episode meeting criteria for any of these 5 C-SSRS Suicidal Behavior Items occurred in the last 2 years

The investigators and participants will remain blinded throughout the study. At the completion of each cohort, the statistician will be unblinded to analyze data.