NCT07058779

Brief Summary

This study was a single-dose, randomized, double-blind, placebo-controlled study of SSS55 injection to evaluate the safety, tolerability, PK characteristics, immunogenicity and preliminary efficacy characteristics of single-dose SSS55 injection in healthy individuals.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
26

participants targeted

Target at P25-P50 for phase_1

Timeline
19mo left

Started Aug 2025

Typical duration for phase_1

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress33%
Aug 2025Dec 2027

First Submitted

Initial submission to the registry

May 26, 2025

Completed
2 months until next milestone

First Posted

Study publicly available on registry

July 10, 2025

Completed
25 days until next milestone

Study Start

First participant enrolled

August 4, 2025

Completed
1.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 1, 2026

Expected
1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2027

Last Updated

March 2, 2026

Status Verified

February 1, 2026

Enrollment Period

1.3 years

First QC Date

May 26, 2025

Last Update Submit

February 26, 2026

Conditions

Outcome Measures

Primary Outcomes (1)

  • To evaluate the safety and tolerability of a single intravenous infusion of SSS55 injection in healthy adult subjects in China

    Number of participants with treatment-related adverse events as assessed by CTCAE v4.0

    22days

Secondary Outcomes (3)

  • To evaluate the pharmacokinetic (PK) characteristics of SSS55 injection after a single intravenous infusion in healthy adult subjects in China

    22days

  • To evaluate the pharmacodynamic characteristics of SSS55 injection after a single intravenous infusion in healthy adult subjects in China

    22 days

  • To evaluate the ADA of SSS55 injection after a single intravenous infusion in healthy adult subjects in China

    22days

Study Arms (4)

Low-dose group

EXPERIMENTAL

dose1

Drug: SSS55

middle-dose group

EXPERIMENTAL

dose 2

Drug: SSS55

high-dose group

EXPERIMENTAL

dose 3

Drug: SSS55

Higher-dose group

EXPERIMENTAL

dose 4

Drug: SSS55

Interventions

SSS55DRUG

SSS55 is an injection targeting complement C3b

Also known as: SSS55 injection
Higher-dose groupLow-dose grouphigh-dose groupmiddle-dose group

Eligibility Criteria

Age18 Years - 45 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Healthy subjects aged 18 to 45 years old (including the boundary value), regardless of gender;
  • The subjects voluntarily participated in the clinical trial and signed the informed consent form;
  • 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);
  • 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;
  • Be willing to receive the MV-ACYW meningococcal vaccine and pneumococcal vaccine 14 days or more before randomization.

You may not qualify if:

  • \) 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;
  • \) 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);
  • \) First-degree relatives with a known history of meningococcal infection or a history of meningococcal infection;
  • \) Those with contraindications to meningococcal vaccination (with a history of epilepsy or other brain diseases, etc.);
  • \) There was or suspected active viral, bacterial, fungal or parasitic infection within 14 days prior to screening, including herpes, shingles or cold sores;
  • \) 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;
  • \) There is a history of Gilbert syndrome or the researcher assesses that it meets the diagnostic criteria for the disease;
  • \) Received treatment with blood products within 6 months prior to administration;
  • \) Those who have undergone major surgical operations within 4 weeks prior to administration or have not fully recovered from any previous invasive procedures;
  • \) 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);
  • \) A history of malignant tumors in the past or present;
  • \) 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.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Shanghai General Hospital

Shanghai, Shanghai Municipality, China

RECRUITING

Central Study Contacts

Ding Chief Pharmacist, Doctor of Medicine

CONTACT

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
OTHER
Intervention Model
SEQUENTIAL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 26, 2025

First Posted

July 10, 2025

Study Start

August 4, 2025

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

December 1, 2027

Last Updated

March 2, 2026

Record last verified: 2026-02

Locations