A Study to Investigate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of AZD4954 in Healthy Adult Participants With or Without Elevated Lipoprotein (a) (Lp[a]) Levels, and Participants With Dyslipidemia

Inclusion Criteria:

All Parts:

• Participants with plasminogen level (concentration) within normal range at theScreening Visit.

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

• Females of childbearing potential must not be lactating and if heterosexually activemust agree to use an approved method of highly effective contraception.

• Females of non-childbearing potential must be confirmed at the Screening Visit.

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

Parts A and B (Healthy Participants):

• Male and female participants aged 18 to 65 years with suitable veins for cannulationor repeated venipuncture.

• Have a body mass index (BMI) between 18 and 35 kg/m² inclusive.

• For Japanese and Chinese participants (Parts A and B):

1. A Japanese participant is defined as having both parents and 4 grandparents whoare ethnically Japanese. This includes second and third generation Japanesewhose parents or grandparents are living in a country other than Japan.

2. A Chinese participant is defined as having both parents and 4 grandparents whoare ethnically Chinese. This includes second and third generation Chinese whoseparents or grandparents are living in a country other than China.Part B (Healthy Participants):

• Participants must have elevated Lp(a) ≥ 30 mg/dL at the Screening Visit.

Part B (Participants with Dyslipidemia):

• Male and female participants aged 18 to 70 years with suitable veins for cannulationor repeated venipuncture.

• Have a BMI > 18 kg/m².

• Participants must have elevated Lp(a) ≥ 70 mg/dL at the Screening Visit.

• Participants with a fasting LDL-C ≥ 70 mg/dL and < 190 mg/L at the Screening Visit.

• Participants should be receiving moderate or high-intensity statin therapy for ≥ 2months prior to the Screening Visit, according to the American College ofCardiology/American Heart Association guidelines on blood cholesterol management.

• Participants with documented coronary artery disease, stroke, or peripheral arterydisease or at moderate or high risk for an atherosclerotic cardiovascular diseaseevent.

• There should be no planned medication or dose change during study participation.

Exclusion Criteria:

All Parts:

• History of any clinically important disease or disorder.

• 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.

• Participants with known bleeding or coagulation disorders.

• Participants who have an elevated high-sensitivity C-reactive protein (> 3 mg/L) orhave a prothrombin time/international normalized ratio (PT/INR) or activated partialthromboplastin time (aPTT) > 1.25 times × upper limit normal (ULN).

• Any clinically important abnormalities in hematology, coagulation, clinicalchemistry, urinalysis, abnormal vital signs or abnormal laboratory values.

• Any positive result on Screening for serum hepatitis B surface antigen (HBsAg),hepatitis B core antibody (HBcAb), hepatitis C virus (HCV) or human immunodeficiencyvirus (HIV).

• Any clinically important abnormalities in rhythm, conduction, or morphology of theresting 12-lead electrocardiogram (ECG) at Screening.

• Use of drugs with enzyme inducing properties such as St John's Wort within 3 weeksprior to the first administration of study intervention.

Parts A and B (Healthy Participants):

• Use of any prescribed or nonprescribed medication including antacids, analgesics (other than paracetamol/acetaminophen), herbal remedies, intake of > 3 × dailyrecommended levels of vitamins and minerals during the 2 weeks prior to the firstadministration of study intervention or longer if the medication has a longhalf-life.

• Current smokers or those who have smoked or used nicotine products.

Part B (Participants with Dyslipidemia):

• Acute ischemic cardiovascular event in the last 12 months prior to randomization.

• Poorly controlled diabetes.

• Previous administration of Lp(a) inhibitor.

• Have uncontrolled hypertension.

• Abnormal vital heart rate.