Safety, Tolerability, PK and PD of SSS55 in Healthy Subjects

Launched by SHENYANG SUNSHINE PHARMACEUTICAL CO., LTD. · Jun 30, 2025

Keywords

ClinConnect Summary

This clinical trial is studying a new medicine called SSS55 to see if it is safe and well-tolerated when given as a single injection to healthy adults. The main goal is to understand how the body processes the medicine, if it causes any side effects, and how the immune system responds to it. This study is in an early phase, meaning it is the first step to test the medicine in people, and it will compare SSS55 to a placebo (a harmless injection) without anyone knowing which one they receive until the study is over.

To join this trial, participants need to be healthy adults between 18 and 45 years old who meet certain health requirements, like having a normal weight and no serious medical conditions. They also must be willing to receive certain vaccines before the study starts. Participants can expect to go through health checks, including blood tests, physical exams, and scans, to make sure they are healthy enough. Since this is a safety study, careful monitoring will happen after the injection to watch for any side effects. It’s important to note that people with allergies, recent infections, or certain medical histories won’t be eligible to join. This trial is not yet recruiting, but it aims to gather important information to help develop SSS55 safely in the future.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • 1. Healthy subjects aged 18 to 45 years old (including the boundary value), regardless of gender;
• • 2. The subjects voluntarily participated in the clinical trial and signed the informed consent form;
• • 3. Men with a weight of ≥50 kg, women with a weight of ≥45 kg, and those with a body mass index (BMI) ranging from 19 to 28 kg/m2 (including the critical value);
• • 4. Those who underwent vital sign assessment, physical examination, blood routine, urine routine, blood biochemistry, coagulation function, pregnancy examination (for women of childbearing age), 12-lead ECG, chest X-ray/lung CT during screening, and the results showed no abnormalities or the abnormalities had no clinical significance;
• • 5. Be willing to receive the MV-ACYW meningococcal vaccine and pneumococcal vaccine 14 days or more before randomization.
• Exclusion Criteria:
• • 1) Those with a clear history of drug or food allergies, or a known history of hypersensitivity reactions that are clinically significant to the research intervention measures or related compounds or commonly used antibacterial agents;
• • 2) Those with a history of any serious clinical diseases in the past or present, including but not limited to those in the digestive system, cardiovascular system, respiratory system, urinary system, musculoskeletal system, endocrine system, immune system, neuropsychiatric system, hematological system, etc. (except those deemed eligible for enrollment by the researcher);
• • 3) First-degree relatives with a known history of meningococcal infection or a history of meningococcal infection;
• • 4) Those with contraindications to meningococcal vaccination (with a history of epilepsy or other brain diseases, etc.);
• • 5) There was or suspected active viral, bacterial, fungal or parasitic infection within 14 days prior to screening, including herpes, shingles or cold sores;
• • 6) A history of recurrent infections of unknown cause; Or systemic antibiotics (intravenous antibiotics, oral antibiotics, etc., excluding topical application antibiotics) have been used within 90 days before administration;
• • 7) There is a history of Gilbert syndrome or the researcher assesses that it meets the diagnostic criteria for the disease;
• • 8) Received treatment with blood products within 6 months prior to administration;
• • 9) Those who have undergone major surgical operations within 4 weeks prior to administration or have not fully recovered from any previous invasive procedures;
• • 10) Suffering from syphilis (Treponema pallidum antibody positive) or AIDS (HIV antibody positive), or active hepatitis C (hepatitis C virus antibody positive), or active hepatitis B (hepatitis B surface antigen positive);
• • 11) A history of malignant tumors in the past or present;
• • 12) Any drugs (including prescription drugs, over-the-counter drugs, Chinese herbal medicines, etc.) or health supplements have been used within 2 weeks before administration (if determined by the investigator, the time interval from the start of administration of the drug in this trial \> Five half-lives, and the corresponding subjects can also be enrolled.