A Dose Escalation Phase 1 Study of HXN5003 in Healthy Participants

1. Participants must sign an Institutional Review Board (IRB) approved informed consent form before any study specific procedure.
2. Male and female participants aged between 18 to 55 years, inclusive.
3. Participants must have a body mass index between 18 to 32 kg/m2, inclusive.
4. Able to participate and comply with all study procedures and restrictions
5. Participants must be willing to understand and comply with all research procedures and restrictions, and able to communicate effectively with researchers.

Exclusion Criteria:

1. Females who are pregnant, planning to become pregnant, or lactating during the trial.
2. Participant who has history or evidence of any active or suspected infection within the past 14 days prior to randomization;
3. Participant who has known positive tuberculin skin test or recent exposure to an individual with active tuberculosis (TB), or current clinical or laboratory evidence of active TB.
4. Participant who has history of malignancy within 5 years before randomization, excluding localized basal cell carcinoma or cutaneous squamous cell carcinoma of the skin that have been resected or cured..
5. Participant who has known type I/II diabetes.
6. Positive for human immunodeficiency virus (HIV) antibodies, syphilis test, hepatitis B surface antigen, or hepatitis C antibodies.
7. Participant who has tested positive for drugs use at Screening or before randomization;
8. Participant who has used nicotine or tobacco containing products within 3 months (>5 cigarettes or an equivalent amount of tobacco per day)
9. Participant who has a history of alcohol abuse (alcohol consumption in excess of 14 units per week
10. Participant who has received an experimental agent (vaccine, drug, biologic, device, blood product or medication) within 30 days or 5 half-lives prior to dosing, or plan to receive another experimental agent during the duration of this trial;
11. Participants who have donated blood (excluding plasma donations) of approximately 1 pint (500 mL) or more within 30 days prior to dosing.
12. Use of prescription or over-the-counter drugs or dietary or herbal supplements within 7 days or 5 half-lives (whichever is longer) prior to dosing;
13. Recent exposure to live vaccines within 30 days, or non-live vaccines (including mRNA COVID/flu) within 2 weeks prior to randomization,
14. Participants with herpes zoster reactivation or cytomegalovirus (CMV) that resolved less than 60 days prior to signing informed consent.
15. Abnormal renal function estimated glomerular filtration rate calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation \< 70mL/min/1.73m2
16. Triplicate 12-lead electrocardiogram (ECG) that demonstrates clinically relevant abnormalities that may affect participant safety or interpretation of study results
17. Participant who has clinically significant interventional therapies (surgery, paracentesis, etc.) within 6 months prior to randomization, or plan to have any surgeries during the duration the trial;
18. History of any severe hypersensitivity or allergic reaction (i.e. anaphylaxis or angioedema) to any drug;
19. History of, or current, clinically relevant acute or chronic medical conditions or diseases of the cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrinological, hematological, neurologic, psychiatric, immunologic, Gilbert's Syndrome and allergic disease or any other condition, in the opinion of the Investigator, might interfere with the absorption, distribution, metabolism, or excretion of study drug; or place the participant at risk in this study or interfere with the interpretation of data.
20. Unwilling or unable to comply with the criteria in the Lifestyle Considerations section of this protocol.