Respiratory Syncytial Virus Infections
Conditions
Keywords
Live attenuated vaccine, Safety, Immunogenicity, Phase 1 clinical trial, Pediatric, Seropositive
Brief summary
This study evaluates an investigational vaccine that is designed to protect humans against infection with respiratory syncytial virus (RSV) and is administered as drops in the nose. Specifically, the study analyzes the safety of, and the immune response to, the vaccine when administered to healthy children between the ages of 15 and 59 months who are seropositive to RSV.
Interventions
Single dose administered intranasally on Day 1
Single dose administered intranasally on Day 1
OTHERPlacebo
Single dose administered intranasally on Day 1
BIOLOGICALInvestigational RSV vaccine MV-012-968 (Dosage 3)
Single dose administered intranasally on Day 1
Sponsors
Meissa Vaccines, Inc.
Study design
Allocation
RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
PREVENTION
Masking
SINGLE (Subject)
Masking description
The study is single-mask in 2 of the 3 dosage groups: study participants and their parent(s)/guardian(s) will not know their child's study assignment, whereas investigators, site staff, and site pharmacists will remain unmasked.
Intervention model description
The first 15 enrolled participants will be assigned to Dosage Group 1 and be randomly allocated to receive either investigational vaccine at Dosage 1 or placebo. The Safety Monitoring Committee will subsequently review Dosage Group 1 safety data through Day 14, to allow dosage escalation. The next 15 enrolled participants will be assigned to Dosage Group 2 and be randomly allocated to receive investigational vaccine at Dosage 2 or placebo. The Safety Monitoring Committee will subsequently review Dosage Group 2 safety data through Day 14, to allow dosage escalation. The final group (Dosage Group 3) will consist of up to 12 enrolled participants who will be allocated to receive investigational vaccine at Dosage 3.
Eligibility
Sex/Gender
ALL
Age
15 Months to 59 Months
Healthy volunteers
Yes
Inclusion criteria
Key Inclusion Criteria: 1. Children aged 15-59 months 2. Good health based on history, physical examination and medical record review, without evidence or suspicion of chronic disease 3. Seropositive to RSV, as defined by serum neutralizing antibody titer above the threshold described in the study Analytical Plan 4. Written informed consent provided by parent(s)/guardian(s) Key
Exclusion criteria
1. Known or suspected chronic illness, particularly cardiopulmonary (including asthma or reactive airways disease), metabolic, hepatic, renal, or infectious (including recurrent or chronic sinusitis) 2. Known or suspected immunodeficiency 3. Household or close contact with anyone ≤ 6 months of age or with immunocompromised individual(s) 4. Nasal obstruction (including due to anatomic/structural causes, acute or chronic rhinosinusitis, or other causes) 5. Receipt of immunoglobulins, monoclonal antibodies and/or any blood products, or ribavirin within 3 months prior to study inoculation, or planned during study period 6. Receipt of an investigational RSV vaccine at any time 7. Any other condition that, in the judgment of the investigator, would be a risk to participant's safety and/or may interfere with study procedures or interpretation of results
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Solicited adverse events (AEs) | Immediate post-vaccination period | Frequency of solicited AEs will be measured, categorized by severity. Solicited AEs are predefined AEs that may occur after investigational vaccine administration |
| Unsolicited AEs | Immediate post-vaccination period | Frequency of unsolicited AEs will be measured, categorized by severity. Unsolicited AEs are any untoward medical occurrences in a participant administered the investigational vaccine, regardless of causal relationship to the investigational vaccine. Unsolicited AEs can include unfavorable and unintended signs (including abnormal laboratory findings), symptoms, or diseases temporally associated with the use of the investigational vaccine. |
| Serious adverse events (SAEs) | Full study duration, an average of 6 months | Frequency of SAEs will be measured, categorized by vaccine-relatedness. SAEs are AEs, whether considered causally related to the investigational vaccine or not, that threaten life or result in any of the following: death, inpatient hospitalization or prolongation of existing hospitalization, persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions, or congenital anomaly/birth defect. |
| Medically attended adverse events (MAEs) | Full study duration, an average of 6 months | Frequency of MAEs will be measured, categorized by vaccine-relatedness. MAEs are AEs, whether considered causally related to the investigational vaccine or not, with unscheduled medically attended visits, such as urgent care visits, acute primary care visits, emergency department visits, or other previously unplanned visits to a medical provider. Scheduled medical visits such as routine physicals, wellness checks, 'check-ups', and vaccinations, are not considered MAEs. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Potential vaccine virus shedding: magnitude | Baseline through Day 28, an average of four (4) weeks | If post-vaccination shedding of vaccine virus is detected by culture, peak viral titer (measured in plaque forming units, PFU) will be measured per dosage group and overall. |
| Change in serum RSV-specific neutralizing antibody titers | Baseline through Day 28, an average of six (6) weeks | Change in serum RSV-specific neutralizing antibody (nAb) titers will be measured per participant. |
| Potential vaccine virus shedding: duration | Baseline through Day 28, an average of four (4) weeks | If post-vaccination shedding of vaccine virus is detected by culture, duration of shedding (in days) will be measured per dosage group and overall. |
| Change in serum binding (RSV F-specific) antibody titers | Baseline through Day 28, an average of six (6) weeks | Change in serum binding (RSV F-specific) antibody titers will be measured per participant. |
| Change in nasal mucosal binding (RSV F-specific) antibody titers | Baseline through Day 28, an average of six (6) weeks | Change in mucosal binding (RSV F-specific) antibody titers will be measured per participant. |
| Potential vaccine virus shedding: frequency | Baseline through Day 28, an average of four (4) weeks | Frequency of any post-vaccination shedding of vaccine virus (as detected by viral culture) will be measured per dosage group and overall. |
Countries
United States
Outcome results
None listed