A Study to Evaluate the Immunogenicity and Safety of a Recombinant Respiratory Syncytial Virus Vaccine in Older Adults Aged 60 Years and Older

NCT07208461 | Active Not Recruiting Phase 2 DMC

• 1 other identifier: LYB005/CT-CHN-201
• Study Type: interventional
• Target: 700
• Locations: 1 country
• Sites: 1

Brief Summary

This is a randomized, observer-blinded, placebo-controlled Phase Ⅱ clinical trial to evaluate the immunogenicity and safety of the Respiratory Syncytial Virus (RSV) Vaccine, LYB005 in participants aged 60 years and older.

Conditions

Respiratory Syncytial Virus Infection Prevention

Keywords

Respiratory Syncytial Virus; Respiratory Syncytial Virus Infection; Recombinant Respiratory Syncytial Virus (RSV) Vaccine

Outcome Measures

Primary Outcomes (2)

• The geometric mean titer (GMT) of Neutralizing Antibodies Against RSV A and RSV B

  Measured by microneutralization assay.

  30 days after vaccination

• Geometric Mean Fold Rise (GMFR) for Neutralizing Antibodies Against RSV A and RSV B

  Change from prevaccination in geometric mean fold rise of Neutralizing antibody titer Against RSV A and RSV B

  30 days after vaccination

Secondary Outcomes (8)

• The GMT of Neutralizing Antibodies Against RSV A and RSV B

  14 days, 3 months, 6 months and 12 months after vaccination after vaccination

• GMFR for Neutralizing Antibodies Against RSV A and RSV B

  14 days, 3 months, 6 months and 12 months after vaccination

• The geometric mean concentration (GMC) for Pre-fusion Protein Specific Binding Antibodies

  30 days, 3 months, 6 months and 12 months after vaccination

• GMFR for Pre-fusion Protein Specific Binding Antibodies

  30 days, 3 months, 6 months and 12 months after vaccination

• Occurrence of immediate adverse events

  Within 30 minutes after vaccination

Study Arms (7)

Low dose antigen of LYB005 without A01B adjuvant

EXPERIMENTAL

Participant aged 60 years and older will be vaccinated with 1 dose of LYB005 (low dose antigen without A01B adjuvant) at Day 0.

Biological: Low dose antigen of LYB005 without A01B adjuvant

Low dose antigen of LYB005 with A01B adjuvant

EXPERIMENTAL

Participant aged 60 years and older will be vaccinated with 1 dose of LYB005 (low dose antigen with A01B adjuvant) at Day 0.

Biological: Low dose antigen of LYB005 with A01B adjuvant

Middle dose antigen of LYB005 without A01B adjuvant

EXPERIMENTAL

Participant aged 60 years and older will be vaccinated with 1 dose of LYB005 (middle dose antigen without A01B adjuvant) at Day 0.

Biological: Middle dose antigen of LYB005 without A01B adjuvant

Middle dose antigen of LYB005 with A01B adjuvant

EXPERIMENTAL

Participant aged 60 years and older will be vaccinated with 1 dose of LYB005 (middle dose antigen with A01B adjuvant) at Day 0.

Biological: Middle dose antigen of LYB005 with A01B adjuvant

High dose antigen of LYB005 without A01B adjuvant

EXPERIMENTAL

Participant aged 60 years and older will be vaccinated with 1 dose of LYB005 (high dose antigen without A01B adjuvant) at Day 0.

Biological: High dose antigen of LYB005 without A01B adjuvant

High dose antigen of LYB005 with A01B adjuvant

EXPERIMENTAL

Participant aged 60 years and older will be vaccinated with 1 dose of LYB005 (high dose antigen with A01B adjuvant) at Day 0.

Biological: High dose antigen of LYB005 with A01B adjuvant

Placebo

PLACEBO COMPARATOR

Participants aged 60 years and older will be vaccinated with 1 dose of placebo at Day 0.

Biological: Placebo

Interventions

Middle dose antigen of LYB005 with A01B adjuvant BIOLOGICAL

0.5 mL per dose, containing a total of 60 μg antigen adjuvanted with A01B.

Middle dose antigen of LYB005 with A01B adjuvant

High dose antigen of LYB005 without A01B adjuvant BIOLOGICAL

0.5 mL per dose, containing a total of 120 μg antigen without A01B adjuvant.

High dose antigen of LYB005 without A01B adjuvant

High dose antigen of LYB005 with A01B adjuvant BIOLOGICAL

0.5 mL per dose, containing a total of 120 μg antigen adjuvanted with A01B.

High dose antigen of LYB005 with A01B adjuvant

Placebo BIOLOGICAL

0.5 mL 0.9% sodium chloride (normal saline) injection per dose

Placebo

Low dose antigen of LYB005 without A01B adjuvant BIOLOGICAL

0.5 mL per dose, containing a total of 30 μg antigen without A01B adjuvant.

Low dose antigen of LYB005 without A01B adjuvant

Low dose antigen of LYB005 with A01B adjuvant BIOLOGICAL

0.5 mL per dose, containing a total of 30 μg antigen adjuvanted with A01B.

Low dose antigen of LYB005 with A01B adjuvant

Middle dose antigen of LYB005 without A01B adjuvant BIOLOGICAL

0.5 mL per dose, containing a total of 60 μg antigen without A01B adjuvant.

Middle dose antigen of LYB005 without A01B adjuvant

Eligibility Criteria

• Age: 60 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Residents aged 60 years and older (at the time of screening), regardless of gender;
• Participants can provide valid identification, voluntarily agree to participate in the study, and sign the Informed Consent Form, and are able to attend all planned follow-up visits and comply with the protocol requirements;
• Axillary temperature \< 37.3°C on the day of enrollment;
• Female participants must be postmenopausal (postmenopausal status defined as amenorrhea for 12 months without other medical causes) and must not intend to become pregnant by any means. Male participants must practice strict contraception and avoid plans for procreation or sperm donation from the screening period until 1 month after vaccination. Acceptable methods of contraception include oral contraceptives (excluding emergency contraception), injectable or implantable contraception, sustained-release local contraceptives, contraceptive patches, intrauterine devices, sterilization, abstinence, condoms, diaphragms, and cervical caps.

You may not qualify if:

• Allergy to the investigational vaccine or its excipients, or a history of anaphylactic shock or other serious adverse reactions to other vaccines;
• Previous vaccination against Respiratory Syncytial Virus;
• A confirmed diagnosis or etiological evidence of respiratory syncytial virus infection and related diseases caused by the infection within 12 months before enrollment;
• Has taken antipyretics, analgesics or anti-allergy drugs within 24 hours before enrollment;
• Has received any vaccine within 14 days before vaccination, or have received a live vaccine within 28 days;
• Has received blood or blood-related products, including immunoglobulin, within 3 months prior to enrollment; or plan to use them during the study period;
• Individual with the following diseases: ①Has acute diseases or are in the acute exacerbation period of chronic diseases within 3 days before vaccination; ②Diagnosed with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; ③History of congenital or acquired immunodeficiency or autoimmune diseases; Chronic administration (≥14 consecutive days) of corticosteroids (dose ≥ 20 mg/day prednisone or equivalent dose) or other immunosuppressants within the past 3 months, with the exception of inhaled or topical steroids, or short-term use (\<14 consecutive days) of oral corticosteroids; ④Neurological diseases or family history (seizures, epilepsy, encephalopathy, etc.); history of psychiatric disorders or family history; ⑤Asplenia or functional asplenia; ⑥Severe or uncontrolled or hospitalization-required cardiovascular diseases, diabetes, blood and lymphatic system diseases, immune system diseases, liver and kidney diseases, respiratory system diseases, metabolic and skeletal system diseases, or malignant tumors; ⑦Contraindications for intramuscular injection and blood drawing, such as coagulation disorders, thrombosis or hemorrhagic diseases, or situations requiring continuous use of anticoagulants; ⑧Severe hypertension that cannot be controlled by medication (measured on-site: systolic blood pressure ≥ 160 mmHg and/or diastolic blood pressure ≥ 100 mmHg);
• History of major surgery within 12 weeks prior to enrollment (as determined by the investigator), or not fully recovered from the surgery, or having plans for major surgery during the anticipated period of the subject's participation in the study;
• History of long-term alcohol abuse and/or drug abuse;
• Individual who is currently participating in other research or unregistered product (drugs, vaccines, or devices, etc.) clinical studies, or plan to participate in other clinical studies before the end of this clinical study;
• Other conditions that may impact the subject's safety or influence the assessment of vaccine response, as determined by the investigator.

Sponsors & Collaborators

• Guangzhou Patronus Biotech Co., Ltd.: lead

Study Sites (1)

Center for Disease Control and Prevention of Dangyang City

Dangyang, China

Location

MeSH Terms

Conditions

Respiratory Syncytial Virus Infections

Condition Hierarchy (Ancestors)

Pneumovirus Infections; Paramyxoviridae Infections; Mononegavirales Infections; RNA Virus Infections; Virus Diseases; Infections

Study Officials

• Yeqing Tong

  Hubei Provincial Center for Disease Control and Prevention

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 27, 2025
• First Posted: October 6, 2025
• Study Start: October 21, 2025
• Primary Completion: March 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: February 11, 2026

Record last verified: 2026-02

Locations

CN (1)