Clinical trial NCT06663436: A Study on the Immune Response and Safety of a Multicomponent Shigella Vaccine in Preventing Shigellosis in Infants
Official title: A Phase 2 Single-Blind, Randomized, Controlled, Single Center Study to Assess the Immunogenicity and Safety of a 2-Dose Schedule With GVGH altsonflex1-2-3 Vaccine in African Infants (H06_02TP)
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: PHASE2
Conditions: Diarrhoea
Keywords: Shigella
Shigellosis
altSonflex1-2-3
Infants
African
Safety
Immunogenicity
Lead sponsor: GlaxoSmithKline
Sponsor class: INDUSTRY
First posted: 2024-10-29
Enrollment: 200
Sex: ALL
Minimum age (years): 39
Maximum age (years): 43
Standard ages: CHILD
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: This study evaluates the immune response and safety of a multicomponent, 2-dose Shigella vaccine in preventing shigellosis in African infants. The candidate vaccine, altSonflex1-2-3, is currently being evaluated in a Phase 2 age de-escalation (from least vulnerable adult population to most vulnerable paediatric population) clinical study in Kenya, with the aim of identifying a preferred dose, using a 3-dose vaccination schedule in infants from 9 months of age (NCT05073003). This Phase 2 clinical study will evaluate the safety and immunogenicity of an alternative 2-dose vaccination schedule.


Eligibility criteria: Inclusion Criteria:

* Participants' parent(s)/ Legally acceptable representative (LAR), who, in the opinion of the investigator, can and will comply with the requirements of the protocol.
* Written or witnessed/thumb printed informed consent obtained from the parent(s)/LAR(s) of the participant prior to performance of any study specific procedure.
* Healthy participants as established by medical history, clinical examination, and laboratory assessment.
* Participants satisfying all screening requirements.
* Participants seronegative for hepatitis B, and hepatitis C.
* A male or female 9 months of age at the time of the first study intervention administration.
* Normal nutritional z-score.
* Previously completed routine childhood vaccinations to the best knowledge of the participant's parent(s)/LAR(s).
* Born at a gestation period of \>=37 weeks to the best knowledge of the participant's parent(s)/LAR(s).
* Participants negative for human immunodeficiency virus as confirmed by DNA polymerase chain reaction testing.
* Participants negative for HLA-B27.

Exclusion Criteria:

* Known exposure to Shigella during lifetime of the participant as confirmed during interview with the participant's parent(s)/LAR(s) or documented by participant's records.
* Progressive, unstable, or uncontrolled clinical conditions.
* History (known or suspected) of any reaction or hypersensitivity likely to be exacerbated by any component of the study intervention.
* Major congenital defects, as assessed by the investigator.
* Recurrent history or uncontrolled neurological disorders or seizures.
* Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
* Hypersensitivity (known or suspected), including allergy, to medicinal products, vaccines, or medical equipment whose use is foreseen in this study.
* Clinical conditions representing a contraindication to intramuscular vaccination and blood draws.
* Any behavioral or cognitive impairment or psychiatric disease that, in the opinion of the investigator, may interfere with the participant's ability to participate in the study.
* Acute disease and/or fever (defined as temperature \>=38.0°C) at the time of enrollment.
* Any clinically significant hematological and/or biochemical laboratory abnormality.
* Confirmed positive COVID-19 test during the period starting 30 days before the first administration of study interventions (Day -30 to Day 1).
* Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the study.
* Acute or chronic clinically significant pulmonary, cardiovascular, hepatic, or renal functional abnormality, as determined by physical examination or laboratory screening tests.
* Use of any investigational or non-registered product (drug, vaccine or invasive medical device) other than the study intervention(s) during the period beginning 30 days before the first dose of study intervention(s) (Day -30 to Day 1), or their planned use during the study period.
* Planned administration/administration of a vaccine/product not foreseen by the Protocol in the period starting 21 days before the first dose and ending after the last dose of study intervention(s) administration with the exception of Coronavirus disease 2019 (COVID-19) vaccines and Expanded Program on Immunization (EPI) vaccines.
* Administration of long-acting immune-modifying drugs at any time during the study period.
* Prior receipt of an experimental Shigella vaccine or live Shigella challenge.
* Prior receipt of a Typhoid conjugate vaccine (TCV).
* Administration of immunoglobulins and/or any blood products or plasma derivatives, or bone marrow transplantation, from birth or planned administration during the study period.
* Chronic administration of immune-modifying drugs (defined as more than 14 days consecutive days in total) and/or planned use of long-acting immune-modifying treatments at any time up to the end of the study.
* Concurrently participating in another clinical study, at any time during the study period, in which the participant has been or will be exposed to an investigational or a non-investigational intervention drug or invasive medical device.
* Any study personnel or immediate dependents, family, or household member.
* Child in care.
* Participants who do not meet eligibility criteria for administration of control vaccines.

Primary outcomes:
measure: Geometric mean titers (GMTs) of anti-serotype-specific Shigella lipopolysaccharides/O-antigen (LPS/OAg) serum Immunoglobulin G (IgG)
timeFrame: Day 1 (before administration of Dose 1)
measure: GMTs of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 169 (before administration of Dose 2)
measure: GMTs of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 29 (28 days after administration of Dose 1)
measure: GMTs of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 197 (28 days after administration of Dose 2)
measure: Geometric mean concentrations (GMCs) of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 1 (before administration of Dose 1)
measure: GMCs of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 169 (before administration of Dose 2)
measure: GMCs of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 29 (28 days after administration of Dose 1)
measure: GMCs of anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 197 (28 days after administration of Dose 2)
measure: Number of infants with at least a 4-fold increase in anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 29 compared with baseline (Day 1)
measure: Number of infants with at least a 4-fold increase in anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 197 compared with baseline (Day 1)
measure: Number of infants with at least a 4-fold increase in anti-serotype-specific Shigella LPS/OAg serum IgG
timeFrame: Day 197 compared with pre-Dose 2 (Day 169)
Secondary outcomes:
measure: Number of infants with solicited administration-site events
timeFrame: During 7 days after each study intervention administration (study interventions administered at Day 1 and Day 169)
measure: Number of infants with solicited systemic events
timeFrame: During 7 days after each study intervention administration (study interventions administered at Day 1 and Day 169)
measure: Number of infants with unsolicited adverse events (AEs)
timeFrame: During 28 days after each study intervention administration (study interventions administered at Day 1 and Day 169)
measure: Number of infants with serious adverse events (SAEs) during the entire study period
timeFrame: From Day 1 to Day 197
measure: Number of infants with deviations from laboratory reference values of hematological, renal, and hepatic panel test results
timeFrame: Day 8 compared with baseline (Day 1)
measure: Number of infants with deviations from laboratory reference values of hematological, renal, and hepatic panel test results compared to pre-Dose 2 values
timeFrame: Day 176 compared with pre-Dose 2 (Day 169)
measure: Anti-measles IgG concentrations expressed as GMCs
timeFrame: At Day 1 (before the first MR-VAC vaccination) and Day 197 (28 days after the second MR-VAC vaccination)
measure: Anti-rubella IgG concentrations expressed as GMCs
timeFrame: At Day 1 (before the first MR-VAC vaccination) and Day 197 (28 days after the second MR-VAC vaccination)
measure: Number of infants with measles seroresponse >=150 mIU/mL and >=200 mIU/mL
timeFrame: At Day 197 (28 days after the second MR-VAC vaccination)
measure: Number of infants with rubella seroresponse >=4 IU/mL and >=10 IU/mL
timeFrame: Day 197 (28 days after the second MR-VAC vaccination)
Other outcomes:
Locations:
city: Kericho
country: Kenya
facility: GSK Investigational Site
Study officials:
References: