Trial Outcomes & Findings for Long-term Follow-up of Immunogenicity of a Single Dose of Japanese Encephalitis Chimeric Virus Vaccine (JE-CV) in Toddlers (NCT NCT01001988)

Results Overview

Seroprotection was defined as the proportion of participants with Japanese encephalitis virus neutralizing antibody titers ≥10 1/dil as measured by a JE 50% plaque reduction neutralization test (PRNT50).

Recruitment status

COMPLETED

Study phase

PHASE3

Target enrollment

596 participants

Primary outcome timeframe

Day 0 (pre-vaccination) from study JEC02, Day 28 post-vaccination from study JEC02, and at Years 1, 2, 3, 4, and 5 post-vaccination

Results posted on

2017-11-29

Participant Flow

Study participants were enrolled at 3 sites in Thailand and 2 sites in the Philippines.

A total of 596 participants received a single dose of JE-CV in JEC02 and came to Visit 1 (Year 1) in JEC05; 585 participants were included in the Per Protocol Analysis set.

Participant milestones

Participant milestones
Measure	Study Group Participants received a single dose of JE-CV in Study JEC02 (NCT00735644)
Overall Study STARTED	596
Overall Study COMPLETED	479
Overall Study NOT COMPLETED	117

Reasons for withdrawal

Reasons for withdrawal
Measure	Study Group Participants received a single dose of JE-CV in Study JEC02 (NCT00735644)
Overall Study Protocol Violation	84
Overall Study Withdrawal by Subject	18
Overall Study Lost to Follow-up	15

Baseline Characteristics

Long-term Follow-up of Immunogenicity of a Single Dose of Japanese Encephalitis Chimeric Virus Vaccine (JE-CV) in Toddlers

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Study Group n=585 Participants Participants received a single dose of JE-CV in Study JEC02
Age, Categorical <=18 years	585 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	0 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants
Age, Continuous	26.2 months STANDARD_DEVIATION 1.86 • n=5 Participants
Sex: Female, Male Female	272 Participants n=5 Participants
Sex: Female, Male Male	313 Participants n=5 Participants
Region of Enrollment Philippines	229 participants n=5 Participants
Region of Enrollment Thailand	356 participants n=5 Participants

PRIMARY outcome

Timeframe: Day 0 (pre-vaccination) from study JEC02, Day 28 post-vaccination from study JEC02, and at Years 1, 2, 3, 4, and 5 post-vaccination

Population: Seroprotection was analyzed in the Per Protocol Analysis Set.

Seroprotection was defined as the proportion of participants with Japanese encephalitis virus neutralizing antibody titers ≥10 1/dil as measured by a JE 50% plaque reduction neutralization test (PRNT50).

Outcome measures

Outcome measures
Measure	Study Group n=585 Participants Participants received a single dose of Japanese encephalitis chimeric virus vaccine (JE-CV) in Study JEC02 (NCT00735644)
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Year 2 post-vaccination	90.0 Percentage of participants
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Year 3 post-vaccination	93.1 Percentage of participants
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Year 4 post-vaccination	87.6 Percentage of participants
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Day 0 (pre-vaccination)	2.6 Percentage of participants
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Day 28 post-vaccination	100.0 Percentage of participants
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Year 1 post-vaccination	88.2 Percentage of participants
Percentage of Participants With Japanese Encephalitis Seroprotection Following a Single Dose of JE-CV Year 5 post-vaccination	85.4 Percentage of participants

PRIMARY outcome

Timeframe: Day 0 (pre-vaccination) from JEC02, Day 28 post-vaccination from JEC02, and at Years 1, 2, 3, 4, and 5 post-vaccination

Population: Geometric mean titers were assessed in the Per Protocol Analysis Set.

Geometric mean titers of Japanese encephalitis virus antibodies were assessed using the PRNT50 test.

Outcome measures

Outcome measures
Measure	Study Group n=585 Participants Participants received a single dose of Japanese encephalitis chimeric virus vaccine (JE-CV) in Study JEC02 (NCT00735644)
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Day 0 (pre-vaccination)	5.13 Titers (1/dil) Interval 5.06 to 5.21
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Day 28 post-vaccination	252 Titers (1/dil) Interval 224.0 to 284.0
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Year 1 post-vaccination	76.8 Titers (1/dil) Interval 67.4 to 87.6
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Year 2 post-vaccination	81.4 Titers (1/dil) Interval 71.7 to 92.6
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Year 3 post-vaccination	132 Titers (1/dil) Interval 114.0 to 153.0
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Year 4 post-vaccination	85.8 Titers (1/dil) Interval 74.7 to 98.6
Summary of Geometric Mean Titers of Japanese Encephalitis Virus Antibodies Following a Single Dose of a JE-CV Year 5 post-vaccination	63.3 Titers (1/dil) Interval 54.8 to 73.0

Adverse Events

Study Group

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Medical Director

Sanofi Pasteur

Phone: 800-633-1610

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place