A Multicenter, Randomized, Double-blind, Placebo-controlled Phase II Dose Exploration Clinical Trial Evaluating the Efficacy, Safety, and Pharmacokinetic Characteristics of STC314 Injection Administered Intravenously in Sepsis Patients

This is a randomized, double-blind, placebo-controlled phase II dose exploration study. The aim of this trial is to evaluate the efficacy, safety, and pharmacokinetic characteristics of STC314 injection in sepsis patients receiving loading dose and continuous intravenous infusion, determine the optimal therapeutic dose, and provide supporting evidence for phase III clinical trials. The overall design of the experiment is shown in Figure 1. This experiment consists of three parallel groups, including two treatment groups with different doses of STC314 injection and one placebo control group.

Inclusion criteria

• (1) 18≤ age ≤80 years old, gender is not limited; (2) The subjects or their guardians voluntarily participate in the study and sign the informed consent; (3) being treated in an intensive care unit; (4) Meet the diagnostic criteria for sepsis 3.0, namely:

• There is a confirmed or suspected infection;
• The presence of infection-induced organ dysfunction, i.e., the Sequential Organ failure score (SOFA) ≥2, as known in If there is organ function impairment before infection, that is, SOFA score is greater than 0, it is necessary to compare SOFA score after infection Previous rise ≥2 points. (5) SOFA score ≤ 13 points; (6) The time from meeting the sepsis 3.0 diagnostic criteria to randomization does not exceed 48 hours; (7) Male and female subjects of reproductive age agreed to use an effective contraceptive method from the start of the study until 1 month after the end of dosing.

Exclusion criteria

• (1) The pregnancy test of women of childbearing age before administration is positive, and pregnant or lactating women; (2) Chronic disease has caused serious organ function impairment, or has caused serious complications:

• Heart: New York Heart Association Heart Function Grade IV;
• Lung: chronic respiratory failure requires long-term oxygen therapy;
• Kidney: chronic kidney disease stage 4 or 5;
• Liver: previous liver failure, hepatic encephalopathy or hepatic coma, gastrointestinal bleeding caused by portal hypertension in the past six months; Or Child-Pugh score ≥ 10 points. (3) Cancer patients with cachexia, or due to obstruction, space occupation, extrusion and other reasons, resulting in serious damage to organ function or internal bleeding, Those who have difficulty or have not yet undergone surgical treatment, or who have received chemotherapy or immunotherapy within the last month; (4) The subjects had severe immune deficiency or were using strong immunosuppression: granulocytosis (N<0.5×10^9/L), activity Blood tumor or stage III HIV infection; Are being treated with immune-inducing drugs such as anti-thymocyte globulin (ATG), Antilymphocyte globulin (ALG), interleukin-2 receptor a chain antibody (IL-2RA), and interleukin-6 receptor αantibody (IL-6RA), etc. Continuous use of glucocorticoid therapy for nearly 2 weeks with a daily dose exceeding 200mg equivalent to hydrocortisone; (5) There is active bleeding that is difficult to control effectively; (6) Currently requiring systemic administration of therapeutic doses of anticoagulants (except prophylactic doses); (7) aPTT > 1.5 times the upper limit of normal value; (8) Platelet count < 50 ×10^9/L; (9) The patient needs or is receiving extracorporeal membrane oxygenation (ECMO) treatment; (10) endangered status, the expected survival time is not more than 24 hours; (11) Cardiac arrest, acute myocardial infarction, or massive cerebral infarction in the past 1 week; (12) are receiving or require dialysis or kidney replacement treatment within 6 hours; (13) Combined with severe or more severe burns: the total surface area of the burn exceeds 30% or the area of the third-degree burn exceeds 10%; Or surface Less than 30% of the volume, but the body condition is heavier or have shock, compound injury, respiratory tract burning; (14) Allergic to the active ingredient of the test drug (methylcellobiose sulfate) or excipients (disodium hydrogen phosphate and sodium dihydrogen phosphate); (15) Participants had participated in another clinical study (except those who did not receive intervention) or were participating in another trial within 1 month prior to screening Clinical treatment; (16) The subject's previous or ongoing disease, physical examination or laboratory test results are abnormal, as determined by the investigator to be probable Adversely affect the subject's safety in the study, or may affect the assessment of the subject's clinical or mental state By a wide margin.