Inclusion Criteria:
* Healthy volunteers will be included in Part A or Part B of the study if they satisfy all the following criteria:
1. Must have given written informed consent before any study-related activities are carried out and must be able to communicate well with the researchers, and complete the study according to the study regulations；
2. Body mass index (BMI) ≥ 18.0 and ≤ 26.0 kg/m2, and male participants weighing no less than 50 kg and female participants no less than 45 kg;
3. Medically healthy without clinically significant abnormalities at screening and pre-dose on Day 1, including: vital signs, physical exams, and ECG results, as well as chest image and abdominal ultrasounds, should be within the normal reference range for healthy individuals or slightly outside but still acceptable, with no clinical significance according to the researchers' judgment.
4. Medically healthy without clinically significant findings in serum chemistry, hematology, coagulation and urinalysis tests as judged by the investigator.
5. Male participants and/or female participants who are infertile should be between 18-45 years old at the time of signing the informed consent form (inclusive).
1. Infertile female participants (who are physiologically unable to get pregnant, including postmenopausal or surgically sterile women) must meet at least one of the following:
* Surgically sterile women are defined as those who have a full hysterectomy, bilateral tubal ligation, or bilateral oophorectomy at least 6 weeks before receiving the study, with relevant clinical records.
* Postmenopausal women are defined as women who have not any menstrual bleeding (including periods, irregular bleeding, spotting, etc.) for at least 12 months and have no other cause for amenorrhea (e.g., hormonal contraception, hormone replacement therapy, prior chemotherapy), confirmed with serum follicle-stimulating hormone (FSH) \>40 MIU/mL and estradiol \<40 pg/mL (\<140 pmol/L) to verify postmenopausal status.
2. Male participants and their partners must agree to follow contraceptive guidance throughout the study period, and male participants must not donate sperm during this period.
Exclusion Criteria:
* Healthy volunteers will be excluded from Part A or Part B of the study if there is evidence of any of the following at screening, Day -1 or pre-dose on Day 1:
1. Unable to comply with the requirements of the protocol.
2. History or presence of clinical significance, such as hematologic, kidney, endocrine, lung, gastrointestinal, cardiovascular, liver, mental disorders, or nervous system diseases, or allergic diseases (including drug allergies, such as a history of heparin allergy or heparin-induced thrombocytopenia, but not including untreated, asymptomatic seasonal allergies).
3. An acute illness within 14 days before administration (such as nausea, vomiting, fever, or diarrhea).
4. Currently infection, or experienced a severe infection within 6 months before or during administration (such as infections requiring antibiotic, antifungal, antiparasitic or antiviral medications), or having chronic or recurrent infectious diseases.
5. Trial participants and/or their first-degree relatives have genetic immunodeficiency.
6. Experienced severe trauma or major surgery within 3 months before administration.
7. History of tuberculosis; signs or symptoms of active tuberculosis as judged by the investigator during screening (such as fever, cough, night sweats, and weight loss); chest imaging (e.g., chest X-ray, chest CT scan) at screening or any time within the 6 months prior showing active pulmonary tuberculosis; contact with patients with open tuberculosis within the last 6 months; positive tuberculosis test (QuantiFERON®-TB or T-SPOT.TB test) during screening - those who test positive may not need a chest X-ray.
8. Positive drug test results;
9. Heavy drinkers: Women who usually drink more than 7 drinks per week or men more than 14 drinks per week in the 6 months before screening (1 drink = 150 ml wine, 360 ml beer, or 45 ml spirits) or anyone who tests positive on a breath alcohol test prior to the first study drug administration.
10. Donated more than 500 ml of blood (not including plasma) within 56 days prior to the first study drug administration, or plan to donate blood or blood components during the study or within 1 month after the study.
11. Used other investigational drugs within the following time limits prior to the first study drug administration:
1. Small molecules: 5 half-lives or 30 days (whichever is longer);
2. Biologics: 5 half-lives or 90 days (whichever is longer);
3. Other drugs (including those with insufficient information): 5 half-lives or 90 days (whichever is longer).
12. Used the same type of antibody drug within 7 half-lives prior to the first study drug administration.
13. Use of systemic glucocorticoids, immunosuppressants or modulators, hormone replacement therapy, or any other treatments that could affect drug absorption, distribution, metabolism, or excretion within 30 days before the first dose, or use of any other prescription drugs, over-the-counter drugs, herbal medicines, or dietary supplements (including vitamins and health products) within 14 days prior to the first study drug administration.
14. Anyone testing positive for syphilis-specific antibodies, hepatitis C antibodies (HCV-Ab), hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb), or human immunodeficiency virus serology antibody (HIV-Ab) during the screening period.
15. Vaccination with live virus vaccines, attenuated live vaccines, or any vaccines containing live virus components within 6 weeks before the first dose, during the planned study period, or within 8 weeks after the study ends.
16. Any history of severe or recurrent suicidal behavior, or during the screening period (looking back 12 months) or at baseline, having answered "yes" to suicidal ideation questions 4 or 5 on the Columbia-Suicide Severity Rating Scale (C-SSRS), or any suicidal behavior in the past 5 years, meaning "yes" to any question on C-SSRS regarding suicidal behavior in the past 5 years.
17. Any other situations that the investigator judges as unsuitable for participating in this study.
