About this trial

This is a 2-Stage, Phase I/II Study to Assess the Safety, Reactogenicity, and Immunogenicity of SK Japanese Encephalitis mRNA Vaccines (GBP560) in Healthy Adults (Aged 18 Years and Older)

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

For Stage 1, participant must be 18 to 55 years of age inclusive, at the time of signing the informed consent.

Participants who are healthy as determined by medical evaluation including medical history, vital signs, physical examination, clinical laboratory tests and medical judgement of the investigator.

Participants who are willing and able to attend all scheduled visits and comply with all study procedures.

Body mass index (BMI) within the range of 18.5-29.9 kg/m2 (inclusive) at screening

Disqualifiers

Any clinically significant respiratory symptoms (e.g., cough, sore throat), febrile illness (tympanic temperature >38°C), or acute illness within 24 hours prior to the 1st study vaccination. Prospective participants with these conditions cannot be included until 24 hours after resolution.

History of congenital, hereditary, acquired immunodeficiency, or autoimmune disease.

Any positive test results for hepatitis B surface antigen, hepatitis C antibody, or human immunodeficiency virus (HIV) at screening.

History of bleeding disorder or thrombocytopenia which is contraindicating intramuscular vaccination in the investigator's opinion.

Trial design

Design model

Sequential

Treatments tested in this trial

GBP560-A
Biological/Vaccine
injection volume of 0.5mililiter (mL) with each dose on V2(1day) and V5 (29day) in stage1 and stage2. Low dose: 3μg Mid dose: 15μg High dose: 50μg
GBP560-B
Biological/Vaccine
injection volume of 0.5mL with each dose on V2(1day) and V5 (29day) in stage1 and stage2. Low dose: 3μg Mid dose: 15μg High dose: 50μg
IXIARO
Biological/Vaccine
injection volume of 0.5mL on V2(1day) and V5 (29day) in stage1 and stage2
IMOJEV
Biological/Vaccine
injection volume of 0.5mL on V5 (29day) in stage1 and stage2
Normal Saline (Placebo)
Biological/Vaccine
injection volume of 0.5mL on V2 (1day) in stage1 and stage2 (This is for IMOJEV placebo)

Treatment groups

402 Participants

are divided into 10 treatment groups

10

Treatment groups

See each treatment group below.

Group A: Test group 1-1 (GBP560-A)Experimental treatment 1 intervention

Group B: Test group 1-2 (GBP560-B)Experimental treatment 1 intervention

Group C: Test group1-3 (GBP560-A)Experimental treatment 1 intervention

Group D: Test group1-4 (GBP560-B)Experimental treatment 1 intervention

Group E: Test group1-5 (GBP560-A)Experimental treatment 1 intervention

Group F: Test group1-6 (GBP560-B)Experimental treatment 1 intervention

Group G: Control group1 (IXIARO®)Active comparator 1 intervention

Group H: Control group2 (IMOJEV®)Active comparator 2 interventions

Group I: Test group 2-1 (GBP560-A or B)Experimental treatment 2 interventions

Group J: Test group 2-2 (GBP560-A or B)Experimental treatment 2 interventions

Trial outcomes

Primary outcomes

1

Percentage of participants experiencing any immediate reactions

For all cohort

Time frame

30 minutes (2 hours for the sentinel participants in stage 1) post each vaccination

2

Percentage of participants reporting any solicited local Adverse Event (AE)

For all cohort

Time frame

during the 7 days following each study vaccination

3

Percentage of participants reporting any solicited systemic Adverse Event (AE)

For all cohort

Time frame

during the 7 days following each study vaccination

4

Percentage of participants experiencing any unsolicited Adverse Event (AE)

For all cohort

Time frame

during the 28 days following each study vaccination

Secondary outcomes

1

Seroprotection rate for both the respective and cross JEV strains of each vaccine (SA14-14-2 and Beijing-1 strain) in live-virus neutralizing antibody titers at each time point

For Stage 1

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination

2

Seroresponse rate for both the respective and cross JEV strains of each vaccine (SA14-14-2 and Beijing-1 strain) in live-virus neutralizing antibody titers, from baseline to each subsequent time point.

For stage 1

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination

3

GMT of neutralizing antibody against both the respective and cross JEV strains of each vaccine (SA14-14-2 and Beijing-1 strain) measured by a live-virus neutralization assay (PRNT) at each time point

For stage 1

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination

4

Geometric mean fold rise of neutralizing antibody against both the respective and cross JEV strains of each vaccine (SA14-14-2,Beijing-1 strain), measured by live-virus neutralization assay(PRNT), from each pre-vaccination to each subsequent timepoint

For stage 1

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination.

Other outcomes

1

Seroprotection rate for the heterologous JEV strains of each vaccine (including, but not limited to K95A07, Bennett, JKT 6468, Sangju-v1 strains) in live-virus neutralizing antibody titers at each timepoint.

will be evaluated exclusively in a subset of approximately 20% of participants in stage 1, 10% of participants in stage 2

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination. and 24 months following the 2nd study vaccination (for stage2 only)

2

GMT of neutralizing antibody against the heterologous JEV strains of each vaccine (including, but not limited to K95A07, Bennett, JKT 6468, Sangju-v1 strains) measured by a live-virus neutralization assay (PRNT) at each timepoint

will be evaluated exclusively in a subset of approximately 20% of participants in stage 1, 10% of participants in stage 2

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination. and 24 months following the 2nd study vaccination (for stage2 only)

3

Seroresponse rate for the heterologous JEV strains of each vaccine (including, but not limited to K95A07, Bennett, JKT 6468, Sangju-v1 strains) in live-virus neutralizing antibody titers, from baseline to each subsequent time point

will be evaluated exclusively in a subset of approximately 20% of participants in stage 1, 10% of participants in stage 2

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination. and 24 months following the 2nd study vaccination (for stage2 only)

4

Geometric mean fold rise of neutralizing antibody against the heterologous JEV strains of each vaccine (including,but not limited to K95A07, Bennett, JKT 6468, Sangju-v1) measured by the PRNT assay, from each pre-vaccination to each subsequent time point

will be evaluated exclusively in a subset of approximately 20% of participants in stage 1, 10% of participants in stage 2.

Time frame

At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and at 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination. and 24 months following the 2nd study vaccination (for stage2 only)

A Study to Assess the Safety, Reactogenicity, and Immunogenicity of SK Japanese Encephalitis Messenger Ribonucleic Acid (mRNA) Vaccines (GBP560) in Healthy Adults

About this trial

Eligibility criteria

Qualifiers

Disqualifiers

Trial design

Treatments tested in this trial

Treatment groups

Trial outcomes

Primary outcomes

Secondary outcomes

Other outcomes

Sponsors and contacts