Respiratory Syncytial Virus (RSV)Phase 1NCT07694557
A Phase 1 Study to Evaluate the Safety, Reactogenicity and Immunogenicity of YKYY025 Injection
A Phase 1 study testing YKYY025 group in people with Respiratory Syncytial Virus (RSV), run by Beijing Youcare Kechuang Pharmaceutical Technology Co., Ltd. at 1 site in China.
Trial summary
A Phase 1 Study to Evaluate the Safety, Reactogenicity and Immunogenicity of YKYY025 Injection Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Respiratory Syncytial Virus (RSV)
- What is being tested?
- YKYY025 group
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 180 participants
- Where
- 1 siteChina
- Study dates
- 29 Jul 2026to 1 Oct 2028
- Phase
- Phase 1
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Male or female participants aged ≥18 to 49 years of age (Part 1) or
- ≥ 50 years of age (Part 2)，can provide legal proof of identity.
- Can understand the study procedures, voluntarily sign the informed consent form after informed consent.
- Able and willing to complete the study procedures during the entire study Follow-up period.
- Body temperature < 37.0°C (Axillary temperature) on the day of enrollment (before vaccination).
- For all women of childbearing potential (WOCBP) females must use an effective contraceptive method from at least 2 weeks prior to study vaccination. All male and female subjects of childbearing potential agree to use a reliable method of contraception (Oral contraceptives (excluding emergency contraceptives), injectable or buried contraceptives, slow-release local contraceptives, hormone patches, intrauterine devices (IUDs), sterilization, abstinence, condoms (male), diaphragm, cervical cap) until at least 6 months after study vaccination.
Who cannot join
- Previously received RSV vaccine or have participated or are currently participating in RSV vaccine clinical trials and have received the trial vaccine.
- A history of confirmed RSV infection or respiratory diseases related to RSV infection within 6 months prior to vaccination.
- Long term (defined as 14 days or more) treatment with immunosuppressants or other immunomodulatory drugs within 6 months prior to vaccination, or planned to receive such treatment within 30 days after vaccination, such as long-term use of systemic corticosteroids (continuous use for 2 weeks or more, dose ≥ 20mg/day prednisone or equivalent prednisone dose, excluding topical medications such as ointments, eye drops, inhalants, or nasal sprays);
- Received immunoglobulin and/or any blood products （such as blood, plasma） within 4 months of vaccination, or planning to receive during the study.
- Have used other experimental or unregistered products (drugs or vaccines) within 30 days before vaccination, or are currently participating in other clinical trials, or planning to participate in other clinical trials during the study.
- Received any live attenuated vaccines/ mRNA vaccine ≤ 28 days prior to vaccination or received any other non live vaccines (recombinant vaccines, subunit vaccines, inactivated vaccines, and other craft vaccines) within 14 days prior to vaccination.
Show all 19Show fewer
- Donate blood or lose a large amount of blood (>450 ml) within 30 days prior to vaccination, or plan to donate blood within 30 days after vaccination.
- Within 3 days prior to vaccination, suffering from acute illness or being in the acute phase of chronic illness, or using antipyretic, analgesic, anti-inflammatory, and/or anti allergic drugs.
- History of severe hypersensitivity reactions to any vaccine or medication, or known to be allergic to any component of the test vaccine, including rapid onset severe allergic reactions or other serious adverse reactions to mRNA vaccine administration.
- Previous or current congenital or acquired immunodeficiency disease (such as AIDS), systemic lupus erythematosus or other autoimmune diseases (such as Guillain Barre syndrome, multiple sclerosis, neuromyelitis optica and other inflammatory demyelinating neuropathy history); Other diseases that affect immune function (such as splenomegaly or functional splenomegaly).
- History of heart diseases such as myocarditis and pericarditis, or having any diseases that increase the risk of myocarditis or pericarditis (including cardiomyopathy, endocardial fibrosis, eosinophilic syndrome, hypersensitivity myocarditis, eosinophilic granulomas with polyangitis, persistent myocardial viral (such as enterovirus or adenovirus) infection, etc.).
- Previous or current serious cardiovascular and cerebrovascular diseases (such as congenital heart disease (except for cured atrial septal defect, patent foramen ovale, etc.), supraventricular tachycardia, atrial fibrillation, stroke, cerebral hemorrhage, etc.), liver and kidney diseases (such as chronic hepatitis active or suspected active hepatitis, nephrotic syndrome, uremia, etc.), respiratory diseases (such as chronic obstructive pulmonary disease, asthma, etc.), diabetes with serious complications, malignant tumors, etc.
- Currently or previously suffering from neurological disorders such as epilepsy (if there is a history of seizures), acute disseminated encephalomyelitis, or mental illnesses that affect normal behavior
- Suffering from thrombocytopenia, coagulation dysfunction, or any condition that can be a contraindication for intramuscular injection
- Participants aged 18-59: those with hypertension that cannot be controlled by medication or with systolic blood pressure ≥ 140mmHg and/or diastolic blood pressure ≥ 90mmHg during pre enrollment blood pressure measurement; Participants aged ≥ 60: those with hypertension that cannot be controlled by medication or with systolic blood pressure ≥ 150mmHg and/or diastolic blood pressure ≥ 100mmHg measured before enrollment.
- Planning to become pregnant during the study or Women of Childbearing Potential who have a positive pregnancy test before vaccination or are pregnant or lactating at screening or prior to vaccination.
- Prior to vaccination, if the laboratory testing indicators and/or electrocardiogram examination specified in the protocol show abnormalities that meet the grading standards of level 2 or above, or if the abnormal results are clinically significant and deemed unsuitable for vaccination with the experimental vaccine by the investigator.
- Participants have a positive result for hepatitis B surface antigen, hepatitis C antibody , HIV antibody and anti-Treponema pallidum antibody.
- Any other reason to be excluded in the opinion of the Investigator
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Anning First People's Hospital
Anning, Yunnan
Mingxuan Zhao, zhaomx@yn-cprc.com, zhouyuting@bjykkc.com
About this study
Official title: A Phase 1, Randomized, Double-Blind, Ascending-Dose Study to Evaluate the Safety, Reactogenicity and Immunogenicity of Respiratory Syncytial Virus mRNA Vaccine YKYY025 Injection in Healthy Adult Participants
A Phase 1 Study to Evaluate the Safety, Reactogenicity and Immunogenicity of YKYY025 Injection
Read the detailed description
This is a randomized, double-blind, ascending-dose Phase 1 clinical study to investigate the safety, reactogenicity, and immunogenicity of YKYY025 when administered in healthy adult male and female participants
- Conditions
- Respiratory Syncytial Virus (RSV)
- Being tested
- YKYY025 group, YKYY025 Placebo group
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
YKYY025 groupDrug
intramuscular, a single intramuscular injection of the corresponding dose of YKYY025 for injection
YKYY025 Placebo groupDrug
intramuscular, a single intramuscular injection of the corresponding dose of YKYY025 Placebo
| Study group | Role | What they receive |
|---|---|---|
| YKYY025 group | Active comparator | Not described Receives: Drug: YKYY025 group |
| YKYY025 Placebo group | Placebo comparator | Not described Receives: Drug: YKYY025 Placebo group |
What is being measured
The primary outcome is the main question the study is designed to answer.
Adverse events(AEs）
Measured: within 30 days after vaccination
Serious adverse events (SAEs)
Measured: within 12 months after vaccination
Heart rate in 12-lead electrocardiogram (ECG)
Measured: within 4 days after vaccination
PR interval in 12-lead electrocardiogram (ECG）
Measured: within 4 days after vaccination
RS duration in 12-lead electrocardiogram (ECG)
Measured: within 4 days after vaccination
QT/QTC in 12-lead electrocardiogram
Measured: within 4 days after vaccination
Secondary outcomes (3)
vaccine response rate (defined as at least 2-fold or 4-fold increase in titer/concentration from Baseline to post-vaccination))
Measured: through 12 months post-initial
Antigen-specific T cell levels in PBMC (ELISpot-IFN-γ)
Measured: sampling at Day14, Day30, 3 months and 6 months after vaccination
Antigen-specific T cell levels in PBMC (ELISpot-IL-4)
Measured: sampling at Day14, Day30, 3 months and 6 months after vaccination
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jul 2026
- Study start29 Jul 2026
- Primary completion1 Jul 2028 (estimated)
- Study completion1 Oct 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Respiratory Syncytial Virus (RSV)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 180 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Beijing Youcare Kechuang Pharmaceutical Technology Co., Ltd.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07694557
- Sponsor's protocol ID
- CLSP-YKYY025-Z01
- Status last verified
- Jul 2026
- First submitted
- 2 Jul 2026
- Last updated
- 10 Sep 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 10 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1, Randomized, Double-Blind, Ascending-Dose Study to Evaluate the Safety, Reactogenicity and Immunogenicity of Respiratory Syncytial Virus mRNA Vaccine YKYY025 Injection in Healthy Adult Participants
- ClinicalTrials.gov ID
- NCT07694557
- Acronym / sponsor ID
- CLSP-YKYY025-Z01
- Conditions
- Respiratory Syncytial Virus (RSV)
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 180 participants (estimated)
- Lead sponsor
- Beijing Youcare Kechuang Pharmaceutical Technology Co., Ltd.Industry (pharma, biotech, devices)
- Study start
- 29 Jul 2026 (actual)
- Primary completion
- 1 Jul 2028 (estimated)
- Study completion
- 1 Oct 2028 (estimated)
- First posted
- 10 Jul 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A Phase 1 Study to Evaluate the Safety, Reactogenicity and Immunogenicity of YKYY025 Injection
Detailed description
This is a randomized, double-blind, ascending-dose Phase 1 clinical study to investigate the safety, reactogenicity, and immunogenicity of YKYY025 when administered in healthy adult male and female participants
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| YKYY025 group | Active comparator | Drug: YKYY025 group |
| YKYY025 Placebo group | Placebo comparator | Drug: YKYY025 Placebo group |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Male or female participants aged ≥18 to 49 years of age (Part 1) or
- ≥ 50 years of age (Part 2)，can provide legal proof of identity.
- Can understand the study procedures, voluntarily sign the informed consent form after informed consent.
- Able and willing to complete the study procedures during the entire study Follow-up period.
- Body temperature < 37.0°C (Axillary temperature) on the day of enrollment (before vaccination).
Key exclusion criteria (19 listed)
- Previously received RSV vaccine or have participated or are currently participating in RSV vaccine clinical trials and have received the trial vaccine.
- A history of confirmed RSV infection or respiratory diseases related to RSV infection within 6 months prior to vaccination.
- Long term (defined as 14 days or more) treatment with immunosuppressants or other immunomodulatory drugs within 6 months prior to vaccination, or planned to receive such treatment within 30 days after vaccination, such as long-term use of systemic corticosteroids (continuous use for 2 weeks or more, dose ≥ 20mg/day prednisone or equivalent prednisone dose, excluding topical medications such as ointments, eye drops, inhalants, or nasal sprays);
- Received immunoglobulin and/or any blood products （such as blood, plasma） within 4 months of vaccination, or planning to receive during the study.
- Have used other experimental or unregistered products (drugs or vaccines) within 30 days before vaccination, or are currently participating in other clinical trials, or planning to participate in other clinical trials during the study.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| YKYY025 groupintramuscular, a single intramuscular injection of the corresponding dose of YKYY025 for injection | Drug | YKYY025 group |
| YKYY025 Placebo groupintramuscular, a single intramuscular injection of the corresponding dose of YKYY025 Placebo | Drug | YKYY025 Placebo group |
Primary outcome
Adverse events(AEs）
Time frame: within 30 days after vaccination
Serious adverse events (SAEs)
Time frame: within 12 months after vaccination
Heart rate in 12-lead electrocardiogram (ECG)
Time frame: within 4 days after vaccination
PR interval in 12-lead electrocardiogram (ECG）
Time frame: within 4 days after vaccination
RS duration in 12-lead electrocardiogram (ECG)
Time frame: within 4 days after vaccination
QT/QTC in 12-lead electrocardiogram
Time frame: within 4 days after vaccination
3 secondary outcomes
vaccine response rate (defined as at least 2-fold or 4-fold increase in titer/concentration from Baseline to post-vaccination))
Time frame: through 12 months post-initial
Antigen-specific T cell levels in PBMC (ELISpot-IFN-γ)
Time frame: sampling at Day14, Day30, 3 months and 6 months after vaccination
Antigen-specific T cell levels in PBMC (ELISpot-IL-4)
Time frame: sampling at Day14, Day30, 3 months and 6 months after vaccination
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Sep 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing YKYY025 group in people with Respiratory Syncytial Virus (RSV), run by Beijing Youcare Kechuang Pharmaceutical Technology Co., Ltd. at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 19 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 10 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Yuting Zhou (+86 18606417018, zhouyuting@bjykkc.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Adverse events(AEs） (time frame: within 30 days after vaccination). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Sep 2026.