A Phase I Study of TACI-antibody Fusion Protein Injection (RC18) in Healthy Adult Chinese Subjects

Inclusion Criteria: 1. Voluntarily signed the informed consent as applicable to participate in the study, age 18-55, inclusive, male: female=1:1; 2. Body mass index between 18.5-26 kg/m², inclusive, with a body weight ≥50 kg (male), ≥45 kg (female); 3. Considered "healthy" by the investigator. Healthy status is defined by absence of evidence of any active or chronic disease following a detailed medical and surgical history, as well as a complete physical examination including vital signs, 12-lead ECG, X-ray examination, infectious disease examination, peripheral blood cell count, platelet aggregation and coagulation function, blood chemistry, urine routine and stool routine ( include occult blood); 4. An understanding, ability, and willingness to fully comply with study procedures and restrictions. Exclusion Criteria: 1. History of any hematological, digestive system, respiratory, cardiovascular, renal, neurological, psychiatric disease, metabolic disorders or tumor, which could affect the action, absorption, or disposition of the investigational product, or clinical or laboratory assessments; 2. History of abnormal bleeding or coagulation disorders (e.g. easy bruising, gum bleeding, prolonged bleeding after tooth extraction, joint hemorrhage; anemia in recent 1 year caused by menorrhagia, postpartum hemorrhage, vitamin K deficiency, haemorrhagic diseases caused by acquired coagulation factor antibodies, trauma or post-operative bleeding, etc.); 3. Pregnant or lactating female during screening period; subjects and their partners did not agree to take effective contraceptive measures (such as intrauterine devices, contraceptives or condoms) throughout the study period and within 30 days after the end of the visit period; 4. History of allergic to therapeutic or diagnostic protein products, allergic to two or more drugs and/or non-drug factors; suffering from allergic diseases; 5. History of surgery within six months before signing the informed consent; Willing to undergo surgery within two weeks after the end of the trial (including cosmetic surgery, dental surgery, oral surgery, etc.); 6. Participated an investigational product in recent 3 months; 7. Current use of any prescription or over-the-counter (herbal, vitamins, or healthcare products). Current use is defined as use within 14 days or PK equivalent of 5 half-lives, whichever is longer; 8. History of Bleeding or donated more than 400ml blood 3 months before screening period, or plan to denote blood within 1 month after the trial; 9. Consume more tobacco or alcohol (≥14 units of alcohol per week: one standard unit contains 14g of alcohol, equals to 360ml of beer, 45ml of 40% liquor or 150ml of wine; smokers with more than 5 cigarettes per day.); 10. Consume excessive caffeine-containing beverages, foods that may affect drug metabolism within four weeks before signing informed consent: coffee (≥1100 mL per day), tea (≥2200 mL per day), cola (≥2200 mL per day), energy drinks (≥1100 mL per day), chocolate (≥510 g per day); 11. Positive HIV, HBsAg, Hepatitis C virus, Tubercle Bacillus antibody screen; 12. Researchers believe that there are other factors that are not suitable for participating in the experiment.