FindTrial
Sign In

Trial of a Chikungunya Vaccine, PXVX0317 CHIKV-VLP, in Healthy Adults

A Phase 2 Parallel-Group, Randomized, Double-Blind Study to Assess the Safety and Immunogenicity of PXVX0317 (Chikungunya Virus Virus-Like Particle Vaccine [CHIKV-VLP], Unadjuvanted or Alum-adjuvanted)

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03483961
Enrollment
445
Registered
2018-03-30
Start date
2018-04-18
Completion date
2020-09-21
Last updated
2023-07-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chikungunya Virus Infection

Brief summary

The goal of this Phase 2 trial is to evaluate the immune response to and safety profile of various doses/formulations/and schedules of administration of PXVX0317 in healthy adults. Primary Objective: To assess the immune response to the vaccine Secondary Objectives: To assess the kinetics of the immune response to different doses/formulations/schedules To assess the persistence of immune responses to different doses/formulations/schedules To assess the effect of a booster dose of the vaccine Safety Objective: To assess local and systemic reactions to the vaccine and to describe the safety profile of the vaccine

Detailed description

The trial will explore 8 formulation/schedule combinations of CHIKV VLP vaccine with or without Alhydrogel adjuvant, and will also explore different dose schedules of Day 1 and 15 or Day 1 and 29 or Day 29 only.

Interventions

BIOLOGICALCHIKV VLP/unadjuvanted

Vaccine consists of virus-like particles of chikungunya virus antigens

BIOLOGICALCHIKV VLP/adjuvanted

Adjuvanted formulation includes Alhydrogel

BIOLOGICALPlacebo

Placebo is vaccine diluent alone

Sponsors

Emergent BioSolutions
CollaboratorINDUSTRY
Bavarian Nordic
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 45 Years
Healthy volunteers
Yes

Inclusion criteria

1. Male or female 2. Age 18 to 45 years old (inclusive) 3. Using an acceptable method of contraception (if female of childbearing potential). 4. Able and willing to provide informed consent for study participation.

Exclusion criteria

1. Current acute febrile illness. 2. Clinically significant cardiac, respiratory, or rheumatologic disease, in the opinion of the Investigator. 3. Pregnant or breast-feeding. 4. Laboratory evidence of infection with Hepatitis B/C or HIV. 5. History of chikungunya virus infection. 6. Travel to a World Health Organization-designated chikungunya-endemic region within 30 days prior to Day 1. 7. History of allergic reaction to any component of CHIKV-VLP vaccine, Diluent, or Alhydrogel®. 8. Inability to discontinue systemic immunomodulatory or immunosuppressive medications 30 days prior to Day 1. 9. Received or plans to receive any licensed vaccine from 30 days prior to Day 1 through Day 57. 10. Received or plans to receive an investigational agent from 30 days prior to Day 1 through the duration of study participation. 11. Any other condition that, in the opinion of the Investigator, creates an unacceptable risk to the subject. 12. Any other condition that, in the opinion of the Investigator, may interfere with the conduct of the study or the validity of the data. 13. Any other condition that, in the opinion of the Investigator, creates an unacceptable safety risk for apheresis (Group 9 & 10 only). 14. Restricted venous access that would prevent the collection of PBMCs, plasma, and lymphocytes necessary for participation (Group 9 & 10 only). 15. Weight \< 110 pounds (Group 9 & 10 only)

Design outcomes

Primary

MeasureTime frameDescription
Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.Day 57 (from Day 1 vaccination), 28 days after the last injection.To assess the induction of anti-chikungunya virus (CHIKV) neutralizing antibody geometric mean titers by different formulations and schedules, as measured at 28 days after the last injection (Day 57) for Groups 2-8.

Secondary

MeasureTime frameDescription
Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.At Days 8, 15, 22, 29, 36, and 57.To describe the kinetics of induction of anti-CHIKV neutralizing antibody geometric mean titers by different formulations and schedules for Groups 2-8.
Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.At Days 182, 365, 547, and 760.To assess differences in persistence of neutralizing antibody geometric mean titers induced by different formulations and schedules, as measured up to 731 days after the last injection (Day 760) relative to earlier time points for Groups 2-8.
Boosting of Vaccine-induced Neutralizing Antibody Geometric Mean Titer by a Booster Dose of PXVX0317 for Group 4 Only.Antibody levels will be measured at Day 547 prior to the booster dose and again 28 days later on Day 575 and then at Day 760.To assess the effect of a booster dose of PXVX0317 on neutralizing antibody geometric mean titers when given at Day 547 for Group 4 only. Antibody levels will be measured at Day 547 prior to the booster dose and again 28 days later on Day 575 and then at Day 760.
Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Day 57 (from Day 1 vaccination), 28 days after the last injection.Percentage of participants with an anti-CHIKV neutralizing antibody titer exceeding the following cutoff values: ≥15, 40, 160, 640, and 4-fold rise over baseline.

Countries

United States

Participant flow

Recruitment details

Participants were recruited at 3 U.S. sites.

Participants by arm

ArmCount
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)
20 mcg CHIKV VLP/unadjuvanted (Day 1) // Placebo (Day 15) // 20 mcg CHIKV VLP/unadjuvanted (Day 29) CHIKV VLP/unadjuvanted: Vaccine consists of virus-like particles of chikungunya virus antigens Placebo: Placebo is vaccine diluent alone
53
Group 2: 6 mcg/Adjuvant (Day 1 & 29)
6 mcg CHIKV VLP/adjuvanted (Day 1) // Placebo (Day 15) // 6 mcg CHIKV VLP/adjuvanted (Day 29) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
52
Group 3: 10 mcg/Adjuvant (Day 1 & 29)
10 mcg CHIKV VLP/adjuvanted (Day 1) // Placebo (Day 15) // 10 mcg CHIKV VLP/adjuvanted (Day 29) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
51
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)
20 mcg CHIKV VLP/adjuvanted (Day 1) // Placebo (Day 15) // 20 mcg CHIKV VLP/adjuvanted (Day 29) // 40 mcg CHIKV (Day 547) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
50
Group 5: 6 mcg/Adjuvant (Day 15 & 29)
Placebo (Day 1) // 6 mcg CHIKV VLP/adjuvanted (Day 15) // 6 mcg CHIKV VLP/adjuvanted (Day 29) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
53
Group 6: 10 mcg/Adjuvant (Day 15 & 29)
Placebo (Day 1) // 10 mcg CHIKV VLP/adjuvanted (Day 15) // 10 mcg CHIKV VLP/adjuvanted (Day 29) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
53
Group 7: 20 mcg/Adjuvant (Day 15 & 29)
Placebo (Day 1) // 20 mcg CHIKV VLP/adjuvanted (Day 15) // 20 mcg CHIKV VLP/adjuvanted (Day 29) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
51
Group 8: 40 mcg/Adjuvant (Day 29)
Placebo (Day 1) // Placebo (Day 15) // 40 mcg CHIKV VLP/adjuvanted (Day 29) CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel Placebo: Placebo is vaccine diluent alone
52
Group 9: 20 mcg/Adjuvant (Day 1 & 29)
20 mcg CHIKV VLP/adjuvanted (Day 1) // 20 mcg CHIKV VLP/adjuvanted (Day 29). This group will also have plasmapheresis performed on Day 57 and Leukapheresis on Day 182 CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel
20
Group 10: 40 mcg/Adjuvant (Day 1)
40 mcg CHIKV VLP/adjuvanted (Day 1). This group will also have plasmapheresis performed on Day 22. CHIKV VLP/adjuvanted: Adjuvanted formulation includes Alhydrogel
10
Total445

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004FG005FG006FG007FG008FG009
Overall StudyAdverse Event0010000000
Overall StudyLost to Follow-up76666441110
Overall StudyOther than AE, death, PI decision, LTFU, noncompliance, study terminated, or withdrawal of consent1000000000
Overall StudyWithdrawal by Subject3453421210

Baseline characteristics

CharacteristicGroup 1: 20 mcg/Unadjuvant (Day 1 & 29)Group 2: 6 mcg/Adjuvant (Day 1 & 29)Group 3: 10 mcg/Adjuvant (Day 1 & 29)Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Group 5: 6 mcg/Adjuvant (Day 15 & 29)Group 6: 10 mcg/Adjuvant (Day 15 & 29)Group 7: 20 mcg/Adjuvant (Day 15 & 29)Group 8: 40 mcg/Adjuvant (Day 29)Group 9: 20 mcg/Adjuvant (Day 1 & 29)Group 10: 40 mcg/Adjuvant (Day 1)Total
Age, Categorical
<=18 years
3 Participants1 Participants0 Participants0 Participants0 Participants1 Participants0 Participants0 Participants0 Participants0 Participants5 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
50 Participants51 Participants51 Participants50 Participants53 Participants52 Participants51 Participants52 Participants20 Participants10 Participants440 Participants
Age, Continuous30.4 years
STANDARD_DEVIATION 8.22
31.2 years
STANDARD_DEVIATION 8.26
31.2 years
STANDARD_DEVIATION 7.64
33.7 years
STANDARD_DEVIATION 7.53
30.6 years
STANDARD_DEVIATION 7.72
32.9 years
STANDARD_DEVIATION 7.53
32.4 years
STANDARD_DEVIATION 7.78
31.6 years
STANDARD_DEVIATION 7.82
27.1 years
STANDARD_DEVIATION 7.58
29.6 years
STANDARD_DEVIATION 7.65
31.5 years
STANDARD_DEVIATION 7.86
Day 1 predose (baseline) geometric mean anti-chikungunya luciferase neutralizing antibody titer.7.5 titer7.5 titer7.5 titer7.5 titer7.8 titer7.5 titer7.5 titer7.5 titer8.6 titer9.0 titer7.6 titer
Ethnicity (NIH/OMB)
Hispanic or Latino
3 Participants4 Participants4 Participants3 Participants4 Participants8 Participants2 Participants4 Participants2 Participants1 Participants35 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
50 Participants48 Participants47 Participants47 Participants49 Participants45 Participants49 Participants48 Participants18 Participants9 Participants410 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants1 Participants0 Participants0 Participants1 Participants0 Participants2 Participants
Race (NIH/OMB)
Asian
0 Participants2 Participants1 Participants2 Participants0 Participants1 Participants0 Participants2 Participants1 Participants0 Participants9 Participants
Race (NIH/OMB)
Black or African American
10 Participants9 Participants14 Participants13 Participants14 Participants9 Participants15 Participants7 Participants7 Participants6 Participants104 Participants
Race (NIH/OMB)
More than one race
0 Participants1 Participants0 Participants0 Participants2 Participants2 Participants1 Participants2 Participants0 Participants0 Participants8 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants1 Participants0 Participants1 Participants0 Participants0 Participants0 Participants2 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
43 Participants40 Participants36 Participants35 Participants36 Participants40 Participants34 Participants41 Participants11 Participants4 Participants320 Participants
Region of Enrollment
United States
53 participants52 participants51 participants50 participants53 participants53 participants51 participants52 participants20 participants10 participants445 participants
Sex: Female, Male
Female
30 Participants30 Participants37 Participants32 Participants38 Participants29 Participants27 Participants26 Participants7 Participants3 Participants259 Participants
Sex: Female, Male
Male
23 Participants22 Participants14 Participants18 Participants15 Participants24 Participants24 Participants26 Participants13 Participants7 Participants186 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
EG006
affected / at risk
EG007
affected / at risk
EG008
affected / at risk
EG009
affected / at risk
deaths
Total, all-cause mortality
0 / 530 / 520 / 500 / 510 / 530 / 530 / 510 / 520 / 200 / 10
other
Total, other adverse events
26 / 5335 / 5236 / 5034 / 5129 / 5328 / 5330 / 5134 / 5212 / 204 / 10
serious
Total, serious adverse events
0 / 531 / 522 / 501 / 510 / 530 / 532 / 513 / 520 / 200 / 10

Outcome results

Primary

Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.

To assess the induction of anti-chikungunya virus (CHIKV) neutralizing antibody geometric mean titers by different formulations and schedules, as measured at 28 days after the last injection (Day 57) for Groups 2-8.

Time frame: Day 57 (from Day 1 vaccination), 28 days after the last injection.

Population: Immunogenicity-evaluable: Exposed participants as treated per protocol (no major protocol deviation or exclusion reason prior to unblinding, all doses received, no prohibited medication, and evaluable serum samples within required time frames).

ArmMeasureValue (GEOMETRIC_MEAN)
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.2057.0 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.1116.2 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.1465.3 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.2023.8 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.920.1 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.1206.9 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.1562.8 titer
Group 8: 40 mcg/Adjuvant (Day 29)Anti-CHIKV Neutralizing Antibody Geometric Mean Titer 28 Days After the Last Injection for Groups 2-8.1712.5 titer
Comparison: Groups 2-8 are compared to Group 1.p-value: 0.0015ANOVA
Comparison: Groups 2-8 are compared to Group 1p-value: 0.0761ANOVA
Comparison: Groups 2-8 are compared to Group 1.p-value: 0.9317ANOVA
Comparison: Groups 2-8 are compared to Group 1.p-value: <0.0001ANOVA
Comparison: Groups 2-8 are compared to Group 1.p-value: 0.0045ANOVA
Comparison: Groups 2-8 are compared to Group 1.p-value: 0.1437ANOVA
Comparison: Groups 2-8 are compared to Group 1.p-value: 0.3216ANOVA
Secondary

Boosting of Vaccine-induced Neutralizing Antibody Geometric Mean Titer by a Booster Dose of PXVX0317 for Group 4 Only.

To assess the effect of a booster dose of PXVX0317 on neutralizing antibody geometric mean titers when given at Day 547 for Group 4 only. Antibody levels will be measured at Day 547 prior to the booster dose and again 28 days later on Day 575 and then at Day 760.

Time frame: Antibody levels will be measured at Day 547 prior to the booster dose and again 28 days later on Day 575 and then at Day 760.

Population: Immunogenicity-evaluable: Exposed participants as treated per protocol (no major protocol deviation or exclusion reason prior to unblinding, all doses received, no prohibited medication, and evaluable serum samples within required time frames).

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Boosting of Vaccine-induced Neutralizing Antibody Geometric Mean Titer by a Booster Dose of PXVX0317 for Group 4 Only.Day 547 (pre-boost)223.6 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Boosting of Vaccine-induced Neutralizing Antibody Geometric Mean Titer by a Booster Dose of PXVX0317 for Group 4 Only.Day 575 (post-boost)12325.8 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Boosting of Vaccine-induced Neutralizing Antibody Geometric Mean Titer by a Booster Dose of PXVX0317 for Group 4 Only.Day 760 (post-boost)5874.2 titer
Secondary

Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.

To assess differences in persistence of neutralizing antibody geometric mean titers induced by different formulations and schedules, as measured up to 731 days after the last injection (Day 760) relative to earlier time points for Groups 2-8.

Time frame: At Days 182, 365, 547, and 760.

Population: Immunogenicity-evaluable: Exposed participants as treated per protocol (no major protocol deviation or exclusion reason prior to unblinding, all doses received, no prohibited medication, and evaluable serum samples within required time frames).

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182345.1 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760169.8 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547169.2 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365243.4 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182209.0 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547NA titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365137.5 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760NA titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365226.7 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547NA titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760NA titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182358.4 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365336.6 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 7605365.1 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547215.7 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182486.6 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760NA titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182253.4 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365195.2 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547NA titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547NA titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182303 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760NA titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365246.9 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365302.0 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547NA titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182388.1 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760NA titer
Group 8: 40 mcg/Adjuvant (Day 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 760279.7 titer
Group 8: 40 mcg/Adjuvant (Day 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 182505.7 titer
Group 8: 40 mcg/Adjuvant (Day 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 365491.7 titer
Group 8: 40 mcg/Adjuvant (Day 29)Differences in Persistence of Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 547297.9 titer
Secondary

Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.

To describe the kinetics of induction of anti-CHIKV neutralizing antibody geometric mean titers by different formulations and schedules for Groups 2-8.

Time frame: At Days 8, 15, 22, 29, 36, and 57.

Population: Immunogenicity-evaluable: Exposed participants as treated per protocol (no major protocol deviation or exclusion reason prior to unblinding, all doses received, no prohibited medication, and evaluable serum samples within required time frames).

ArmMeasureGroupValue (GEOMETRIC_MEAN)
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 29417.2 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 572057.0 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 22691.5 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 363442.8 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 870.6 titer
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 15419.3 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 15189.4 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 834.3 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 361675.8 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 571116.2 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 22351.3 titer
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 29277.3 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 29890.5 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 571465.3 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 15530.2 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 872.6 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 362772.4 titer
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 221400.2 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 291238.1 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 222198.1 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 572023.8 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 15912.7 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 8117.6 titer
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 363435.0 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 157.7 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 88.4 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 2246.4 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 29258.0 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 361327.7 titer
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 57920.1 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 157.5 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 571206.9 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 29328.8 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 87.5 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 362155.4 titer
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 2263.1 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 22119.0 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 363609.0 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 157.7 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 571562.8 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 29886.2 titer
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 87.5 titer
Group 8: 40 mcg/Adjuvant (Day 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 298.2 titer
Group 8: 40 mcg/Adjuvant (Day 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 227.5 titer
Group 8: 40 mcg/Adjuvant (Day 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 36157.9 titer
Group 8: 40 mcg/Adjuvant (Day 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 157.5 titer
Group 8: 40 mcg/Adjuvant (Day 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 87.5 titer
Group 8: 40 mcg/Adjuvant (Day 29)Kinetics of Anti-chikungunya Virus (CHIKV) Neutralizing Antibody Geometric Mean Titer for Groups 2-8.Day 571712.5 titer
Secondary

Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.

Percentage of participants with an anti-CHIKV neutralizing antibody titer exceeding the following cutoff values: ≥15, 40, 160, 640, and 4-fold rise over baseline.

Time frame: Day 57 (from Day 1 vaccination), 28 days after the last injection.

Population: Immunogenicity-evaluable: Exposed participants as treated per protocol (no major protocol deviation or exclusion reason prior to unblinding, all doses received, no prohibited medication, and evaluable serum samples within required time frames).

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1547 Participants
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline47 Participants
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64043 Participants
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16047 Participants
Group 1: 20 mcg/Unadjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4047 Participants
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4044 Participants
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64032 Participants
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline44 Participants
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16042 Participants
Group 2: 6 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1544 Participants
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4043 Participants
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline43 Participants
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1544 Participants
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64041 Participants
Group 3: 10 mcg/Adjuvant (Day 1 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16043 Participants
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16045 Participants
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline45 Participants
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1545 Participants
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4045 Participants
Group 4: 20mcg/Adjuvant(Day 1 & 29);40mcg/Adjuvant (Day 547)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64043 Participants
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16047 Participants
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1548 Participants
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4048 Participants
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64029 Participants
Group 5: 6 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline48 Participants
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16048 Participants
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64040 Participants
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4048 Participants
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1548 Participants
Group 6: 10 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline48 Participants
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16046 Participants
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1547 Participants
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4047 Participants
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline47 Participants
Group 7: 20 mcg/Adjuvant (Day 15 & 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64041 Participants
Group 8: 40 mcg/Adjuvant (Day 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4-fold rise over baseline50 Participants
Group 8: 40 mcg/Adjuvant (Day 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 64044 Participants
Group 8: 40 mcg/Adjuvant (Day 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 1550 Participants
Group 8: 40 mcg/Adjuvant (Day 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 16050 Participants
Group 8: 40 mcg/Adjuvant (Day 29)Percentage of Participants With an Anti-CHIKV Neutralizing Antibody Titer Exceeding the Following Cutoff Values: ≥15, 40, 160, 640, and 4-fold Rise Over Baseline.Titer at or above 4050 Participants

Source: ClinicalTrials.gov · Data processed: Feb 17, 2026