RBD5044 in Chinese Participants With Hypertriglyceridemia

The goal of this clinical trial is to learn if drug RBD5044 works to treat hypertriglyceridemia in adults. It will also learn about the safety of drug RBD5044. The main questions it aims to answer are: Does drug RBD5044 reduce the triglyceride levels? What medical problems may participants experience when taking drug RBD5044? Researchers will compare drug RBD5044 to a placebo to see if drug RBD5044 works to treat hypertriglyceridemia. Participants will: Receive RBD5044 or placebo twice during the trial (Day 1 and Day 84).

Inclusion Criteria: 1. The participants consented to participate in the clinical study and signed the informed consent form. 2. Male or nonpregnant (who do not plan to become pregnant) nonlactating female participants aged 18 to 80 years inclusive. 3. Established diagnosis of HTG and prior documented evidence (medical history) of fasting TG level ≥150 mg/dL (≥1.7 mmol/L) and \75 mmol/mol International Federation of Clinical Chemistry \[IFCC\] units) at screening. The participant will be excluded if they have diabetes and meet any of the following criteria: * Two HbA1c readings (≥4 weeks apart) during the screening period, with at least one reading \>9.0%. (If a participant is screen-failed based on HbA1c criteria, the investigator may optimize the anti-diabetic regimen and re-screen the participant.) * Any history of the following within 12 weeks prior to the screening period: diabetic ketoacidosis, diabetic decompensation/hyperosmolar hyperglycemic state, diabetes complications, recurrent infections, or hospitalization due to poor glycemic control. * For participants with insulin-dependent diabetes: Any change in basal insulin of more than ±10 units during the 12 weeks prior to Day 1, indicating an unstable insulin regimen. 7. Received any siRNA for lipids/TGs (other than inclisiran) within 365 days before Day 1. Administration of investigational drug and inclisiran must be separated by at least 4 weeks. 8. Any other siRNA or antisense oligonucleotide within 60 days or 5 target engagement half-lives (whichever is longer), or any other investigational product within 30 days or 5 target engagement half-lives (whichever is longer) before the first dose, with the exception that inclisiran is permitted if administered at least 4 weeks apart from the trial drug. 9. Participants who were positive for hepatitis B surface antigen (HBsAg) and/or hepatitis B core antibody (HBcAb), hepatitis C virus antibody (HCVAb), or human immunodeficiency virus antibody (HIVAb) at screening. 10. Clinically significant illness within 7 days before the first dose of the trial drug. A clinically significant illness is defined as one that is new or acutely worsened, requires intervention, may interfere with study assessments, or significantly increases the participant's risk. 11. Acute pancreatitis within 3 months prior to first investigational product administration. 12. Participants with a history of symptomatic gallbladder disease prior to the first dose (e.g., cholecystitis, choledocholithiasis, multiple gallstones, etc, unless cholecystectomy was performed at least 6 months prior). 13. History of malignancy within the past 5 years (with the exception of cured basal cell carcinoma, localized squamous cell carcinoma of the skin, or carcinoma in situ of the cervix), or currently under evaluation for a potential malignancy. 14. Any planned bariatric surgery or similar procedures to induce weight loss during the period starting at consent through EOS. 15. History of major surgery within 12 weeks or planned major surgery during the study 16. Planned coronary intervention (such as stent placement or heart bypass) during the study. 17. Acute or unstable myocardial ischemia (myocardial infarction, acute coronary syndrome, new angina pectoris, stroke, transient ischemic attack, or unstable congestive heart failure) within 6 months prior to screening or major cardiovascular surgery planned within 3 months after screening. 18. . Recent unstable or symptomatic cardiac arrhythmia requiring hospitalization (including any associated medication changes) within 90 days of the beginning of screening. 19. Alcohol abuse (men drinking more than 14 standard units per week, women drinking more than 9 standard units per week) within 3 months prior to screening. 1 standard unit containing 14g of alcohol, such as 360mL of beer or 45mL of spirits with 40% alcohol or 150mL of wine), or a positive alcohol B-PEth test, at the discretion of the investigator, is not suitable for participation in the study. 20. History or clinical evidence of drug abuse within the 12 months before screening. Drug abuse is defined as compulsive, repetitive, and/or chronic use of drugs or other substances with or without problems related to their use and/or where stopping or a dose reduction will lead to withdrawal symptoms. 21. Donated more than 500 mL of blood within 56 days before the first dose of the trial drug. 22. Participants with severe allergies (multiple drug and food allergies), or allergies to GalNAc and antisense oligonucleotides (ASO) components are determined by the investigator to be unsuitable for participation in this study. 23. History of severe intolerance to subcutaneous (SC) injection (minor reactions are permitted, e.g. localized swelling or redness.). 24. Any conditions which would make the participant unsuitable for enrollment or could interfere with the participant's participation in or completion of the trial in the opinion of the investigator. 25. Unwillingness to comply with lifestyle and diet management requirements. 26. Pregnant or breastfeeding participants or participants intending to become pregnant during the trial and within 90 days after study completion.