A Study to Investigate Safety, Tolerability, and Pharmacokinetics of Oral AZD0233 Compared With Placebo in Healthy Adult Participants.

Inclusion Criteria:

• Healthy male and/or female participants with suitable veins for cannulation orrepeated venipuncture.

• All females must have a negative pregnancy test at the Screening Visit and onadmission to the Clinical Unit.

• Females of non-childbearing potential must be confirmed at the Screening Visit byfulfilling one of the following criteria:

1. Post-menopausal defined as amenorrhea for at least 12 months followingcessation of all exogenous hormonal treatments and follicle-stimulating hormone (FSH) levels in the post-menopausal range.

2. Documentation of irreversible surgical sterilization by hysterectomy, bilateraloophorectomy, or bilateral salpingectomy but not tubal ligation.

• Sexually active fertile male participants with partners of childbearing potentialmust adhere to the specified contraception methods from the time of firstadministration of study intervention until 3 months after the study Follow-up Visit.

• Have a body mass index between 18 and 30 kg/m² inclusive and weigh at least 50 kg.

Note: For Japanese sub-Cohort minimum weight of 45 kg is acceptable.

• For the healthy Japanese sub-Cohorts: healthy Japanese participants (e.g., natives of Japan or Japanese Americans) are defined as having both parents and 4 grandparents who are Japanese. This includes healthy second and third generation participants of Japanese descent whose parents or grandparents are living in a country other than Japan.

Exclusion Criteria:

• History of any clinically important disease or disorder which may either put theparticipant at risk because of participation in the study or influence the resultsor the participant's ability to participate in the study.

• History or presence of gastrointestinal, hepatic, or renal disease or any othercondition known to interfere with absorption, distribution, metabolism, or excretionof drugs.

• Any clinically important illness, medical/surgical procedure, or trauma within 4weeks of the first administration of study intervention.

• Any clinically important abnormalities in clinical chemistry, hematology,urinalysis, laboratory values or vital signs at Screening and/or first admission tothe Clinical Unit.

• Any clinically important abnormalities in rhythm, conduction or morphology of theresting electrocardiogram (ECG) and any clinically important abnormalities in the 12-lead ECG that may interfere with the interpretation of corrected QT (QTc)interval changes in heart rate.

• Current smokers or those who have smoked or used nicotine products (includinge-cigarettes) within the previous 3 months prior to Screening.

• Known or suspected history of alcohol or drug abuse or excessive intake of alcohol.

• Positive screen for drugs of abuse, or alcohol or cotinine at Screening or on eachadmission to the Clinical Unit.

• History of severe allergy/hypersensitivity or ongoing clinically importantallergy/hypersensitivity, or history of hypersensitivity to drugs of a similar classto AZD0233.

• Use of drugs with enzyme [Cytochrome P450 3A (CYP3A)]/ transporter [breast cancerresistance protein (BCRP) and organic anion transporting polypeptide 1B (OATP1B)]inducing/ inhibiting properties such as St John's Wort within 3 weeks prior to thefirst administration of study intervention.

• Use of any prescribed or nonprescribed medication including antacids, analgesics (other than paracetamol/acetaminophen), herbal remedies, mega dose vitamins (intakeof 20 to 600 times the recommended daily dose) and minerals during the 2 weeks priorto the first administration of study intervention or longer if the medication has along half-life. Hormone replacement therapy medications are allowed for femaleparticipants.

• Has received another new chemical entity (defined as a compound which has not beenapproved for marketing) within 30 days or 5 half-lives (whichever is longest) of thefirst administration of investigational medicinal product (IMP) in this study. Theperiod of exclusion begins one month after the final dose.

• Participants who have previously received AZD0233.

• Active systemic bacterial, viral, or fungal infection within 14 days prior to dosingor presence of fever (confirmed tympanic body temperature > 37.6 °C) within 14 daysprior to dosing on Day 1 depending on experienced symptoms.

• Clinically significant serious active and chronic infections within 60 days prior torandomization.

• Known history of primary immunodeficiency (congenital or acquired) or an underlyingcondition that predisposes to infection.

• Concomitant immunosuppressive and/or steroid treatment.

• Any positive result on Screening for serum hepatitis B surface antigen (HBsAg),hepatitis B core antibody (anti-HBc), hepatitis C antibody, human immunodeficiencyvirus (HIV).

• Clinical signs and symptoms consistent with COVID-19.

• Participants who are vegans or have medical dietary restrictions.

• Involvement in the planning and/or conduct of the study (applies to both AstraZenecastaff and/or staff at the Clinical Unit).

• Judgment by the investigator that the participant should not participate in thestudy if they have any ongoing or recent (ie, during the Screening period) minormedical complaints that may interfere with the interpretation of study data or areconsidered unlikely to comply with study procedures, restrictions, and requirements.

• Participants who cannot communicate reliably with the investigator.

• Vulnerable participants, e.g., kept in detention, protected adults underguardianship, trusteeship, or committed to an institution by governmental orjuridical order.