SSS55 safety and how the body handles it in healthy adults

A Randomized, Double-blind, Placebo-controlled Phase I Clinical Study to Evaluate the Safety, Tolerability, Pharmacokinetic and Pharmacodynamic Characteristics of SSS55 Injection in Healthy Subjects in China

This trial tests a single injection of SSS55 in healthy adults to see if it is safe, how the body processes it, and whether it triggers immune responses.

Quick facts

• Phase: Phase 1
• Study type: Interventional
• Enrollment: 26 (estimated)
• Ages: 18 Years to 45 Years
• Sex: All
• Sponsor: Shenyang Sunshine Pharmaceutical Co., LTD. (Industry-sponsored)
• Locations: 1 site (Shanghai, Shanghai Municipality)
• Trial ID: NCT07058779 on ClinicalTrials.gov

What this trial studies

This is a randomized, double-blind, placebo-controlled, single-dose Phase 1 trial in healthy adults that examines safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), immunogenicity, and preliminary efficacy signals. Four dose groups were planned with sentinel dosing: the first two subjects in each group were randomized 1:1 to SSS55 or placebo and observed for 8 days before dosing the remainder of the group. Participants are adults aged 18–45 meeting weight and BMI criteria and must be willing to receive specified vaccines before randomization. The trial is sponsored by Shenyang Sunshine Pharmaceutical and conducted at Shanghai General Hospital.

Who should consider this trial

Good fit: Ideal candidates are healthy men and women aged 18–45 with BMI 19–28 kg/m2, meeting screening labs and physical exam criteria, and willing to receive the required meningococcal and pneumococcal vaccines prior to randomization.

Not a fit: People with significant medical conditions, known drug or food allergies or hypersensitivity, pregnant or breastfeeding individuals, or those outside the age/weight/BMI criteria are unlikely to benefit from participating.

Why it matters

Potential benefit: If successful, the results could show that SSS55 is safe enough to move into patient trials and provide initial data to guide effective dosing.

How similar studies have performed: Single-dose, randomized, placebo-controlled Phase 1 trials measuring PK/PD and immunogenicity are a standard first step for new biologics and have successfully guided development of other agents, but SSS55 itself appears novel and untested in humans.

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.

Where this trial is running

Shanghai, Shanghai Municipality

• Shanghai General Hospital — Shanghai, Shanghai Municipality, China (Recruiting)

Study contacts

• Study coordinator: Ding Chief Pharmacist, Doctor of Medicine

Conditions Safety Issues