To determine pre-existing virus neutralization titer levels against RSV in a general healthy population (immunogenicity is a secondary study objective (proof-of concept) in the main phase I study).
ID
Source
Brief title
Condition
- Respiratory tract infections
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Virus neutralization titer levels against RSV
Secondary outcome
NA
Background summary
Intravacc is developing a live-attenuated recombinant respiratory syncytial
virus (RSV) vaccine. With reverse genetics, a virus was constructed from which
the coding sequence for the G attachment protein was deleted from the RSV
genome. The resulting RSV*G lacks the G protein resulting in severely impaired
binding to host cells and reduced infectivity. Due to this attenuation and
limited spread, the vaccine is expected to induce an effective immune response,
without inducing RSV symptoms. The phase I study (main study) will evaluate the
safety, tolerability and shedding of the RSV vaccine in healthy adults. An
objective will be to evaluate the immunogenicity of the vaccine, the capacity
of the RSV*G vaccine to induce a humoral immune response both systemically and
mucosally (proof-of-concept). Because RSV is a common cold virus, all subjects
will have experienced multiple infections with RSV and have pre-existing
immunity. Therefore, true proof-of-concept, i.e. induction of a functional and
protective primary immune response, can only be established in naïve
individuals (infants). However, a. for prophylactic vaccines safety in healthy
adults is required before proceeding to target populations such as children and
infants and b. it is also of interest to study whether the vaccine is capable
of activating the immune system. The vaccine may boost pre-existing immunity
and induce new immune responses to sub-immunodominant epitopes in the F and SH
surface proteins.
A four-fold increase in RSV serum virus neutralizing antibody titers 28 days
after immunization is indicative for the activation of an immune response
against RSV. For the main study, one of the inclusion criteria is a
pre-existing virus neutralization titer against RSV below a certain level (to
be determined based on the results of the pilot study) at screening. RSV
neutralizing antibody titers can neutralize the vaccine upon administration and
thereby prevent infection, and thereby decrease the effectiveness of the
vaccine. Secondly, when high pre-vaccination titers are present, a rise in
antibody titers induced by the vaccine may not be measurable.
Study objective
To determine pre-existing virus neutralization titer levels against RSV in a
general healthy population (immunogenicity is a secondary study objective
(proof-of concept) in the main phase I study).
Study design
Virus neutralization titer levels against RSV will be determined in 4.0 mL
serum blood samples (RSV-specific IgG). These samples will be collected from a
planned total number of 100 healthy male/female subjects (a single blood sample
donation).
Study burden and risks
1 short visit with 1 blood sample, low risk low burden.
Antonie van Leeuwenhoeklaan 9
Bilthoven 3721 MA
NL
Antonie van Leeuwenhoeklaan 9
Bilthoven 3721 MA
NL
Listed location countries
Age
Inclusion criteria
1.Healthy male or female subjects, 18-45 years of age, inclusive;
2.Signed informed consent prior to any study-mandated procedure
3. Has the ability to communicate well with the Investigator in the Dutch language
Exclusion criteria
1. Immune-compromised individuals (known or expected immune deficiency, disease or use of medication that may affect the immune system);
2. Chronic airway diseases;
3. Airway infection / common cold within 14 days prior to blood sample collection;
4. Hay fever or other allergies that involve the airways;
5. Blood donation would result in loss of blood outside the limits of the national blood bank (>500 mL within 90 days.
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL62098.056.17 |