Chikungunya Virus InfectionPhase 3NCT06007183
Long-term Follow-up Study to Evaluate Safety and Immunogenicity of CHIKV VLP Single or Booster Vaccination
A Phase 3 study testing CHIKV VLP vaccine booster in people with Chikungunya Virus Infection, run by Bavarian Nordic at 24 sites in United States.
Trial summary
The purpose of this phase 3 multicenter, randomized, double-blind, placebo-controlled rollover study is to evaluate the safety and long-term immunogenicity of CHIKV VLP vaccine in adult and adolescent participants and to evaluate CHIKV VLP booster vaccine induced serum neutralizing antibody (SNA) response at 3 or 4… Read more about this study
- Who is it for?
- Ages 12 years and olderHealthy volunteers can take part
- Conditions the study is for
- Chikungunya Virus Infection
- What is being tested?
- CHIKV VLP vaccine booster
- Type of treatment
- Vaccines, Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 715 participants
- Where
- 24 sitesUnited States
- Study dates
- 30 Aug 2023to Feb 2028
- Phase
- Phase 3
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 12 years and older
- All sexes
- Healthy volunteers accepted
- Child, Adult, Older adult
Who may be able to join
- Only within the EBSI-CV-317-004 feeder study informed consent form (ICF) (and/or assent form, as applicable), the participant voluntarily signed and agreed to be contacted or did not indicate they were not to be contacted for potential screening and enrollment in a future study (ie, EBSI-CV-317-008).
- Able and willing to provide informed consent (and assent, as applicable) voluntarily signed by participant (and guardian, as applicable) for participation in this rollover study EBSI-CV-317-008, including possible receipt of a booster dose of CHIKV VLP vaccine.
- Males or females, 12 years of age or older at the time of enrollment in the feeder study.
- Received a single dose of CHIKV VLP vaccine in one of the feeder studies, EBSI-CV-317-004 or EBSI-CV-317-005.
- Demonstrated compliance to the feeder study conduct (ie, rollover participant was without protocol deviations that excluded them from immunogenicity analysis in feeder study EBSI-CV-317-004 or EBSI-CV-317-005) without discontinuation or early withdrawal.
- Generally healthy, in the opinion of the investigator, based on medical history and physical examination.
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- Additional inclusion criteria to be assessed at Prerandomization Visit (Visit 5), before Randomization A (Visit 6), and before Randomization B (Visit 8 for Group 2) to determine eligibility for a booster dose of CHIKV VLP vaccine or placebo:
- Women who are either: i. Not of childbearing potential (CBP): premenarche, surgically sterile (at least six weeks postbilateral tubal ligation or bilateral total salpingectomy, bilateral oophorectomy, or hysterectomy), or postmenopausal (defined as a history of ≥12 consecutive months without menses prior to randomization in the absence of other pathologic or physiologic causes, following cessation of exogenous sex-hormonal treatment). For women who are postmenopausal, documented follicle stimulating hormone (FSH) level of ≥40 mIU/mL must be obtained. If the FSH is <40 mIU/mL, the participant must agree to use an acceptable form of contraception. or: ii. Meet all the below criteria:
- Negative serum pregnancy test at Prerandomization and Prebooster Visits
- Negative urine pregnancy test immediately prior to booster dose administration
- Use one of these acceptable methods of contraception (if women of CBP) for at least six months after booster:
- Hormonal contraceptives (eg, implants, pills, patches) initiated ≥30 days prior to booster dose administration
- Intrauterine device (IUD) inserted ≥30 days prior to booster dose administration
- Double barrier type of birth control (male condom with female diaphragm, male condom with cervical cap)
- Abstinence is acceptable only for adolescents (12-<18 years of age) who are not sexually active.
- Women participants of CBP must use an acceptable method of contraception from ≥30 days prior to Randomization A or assignment to Group 1; those who are randomized to Group 2 at year 3 can discontinue contraception until 30 days prior to booster dose administration, if desired. Women participants of CBP must use an acceptable method of contraception from ≥30 days prior to Randomization B through six-months postbooster vaccination dose (if applicable). Women participants of CBP randomized to Group 3 can discontinue contraception, if desired.
- Note: Contraception requirements do not apply for participants in exclusively same-sex relationships and these participants should have no plans to become pregnant by any other means during the same time period as women of CBP are required to use contraception. Contraception requirements do not apply to Group 4 participants (unrandomized or unboosted).
Who cannot join
- Received placebo treatment in the feeder study.
- Measurable anti-CHIKV SNA at Day 1 in the feeder study.
- History of severe allergic reaction or anaphylaxis to any component of the investigational product (IP).
- Receipt of either an investigational or licensed CHIKV vaccine (excluding prior receipt of CHIKV VLP vaccine).
- New onset/diagnosis of any disease falling within the feeder study exclusion criteria including: i. History of any known congenital or acquired immunodeficiency that could impact response to vaccination (eg, leukemia, lymphoma, generalized malignancy, functional or anatomic asplenia, alcoholic cirrhosis) or ii. Clinically significant cardiac, pulmonary, rheumatologic, or other chronic disease, in the opinion of the investigator. This may include chronic illness requiring hospitalization during the feeder study.
- Evidence of substance abuse that, in the opinion of the investigator, could adversely impact the individual's participation or the conduct of the study.
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- Any other medical condition or general reason that, in the opinion of the investigator, could adversely impact the individual's participation or the conduct of the study.
- Experienced a related safety event in the feeder study that, in the investigator's judgement, precludes receipt of booster.
- Bavarian Nordic staff members and their families, contractors, agents, business partners, and anyone with a financial interest in the outcome of the study.
- Additional exclusion criteria to be assessed at Prerandomization Visit (Visit 5), before Randomization A (Visit 6), and before Randomization B (Visit 8 for Group 2) to determine eligibility for a booster dose of CHIKV VLP vaccine or placebo:
- Participation or planned participation in an investigational clinical trial, excluding feeder studies EBSI-CV-317-004 or EBSI-CV-317-005 (eg, vaccine, drug, medical device, or medical procedure) for the following time periods:
- Group 1: 30 days prior to Randomization A or assignment to Group 1 at Visit 6 through Visit 7 Group 2: 30 days prior to Randomization A at Visit 6 until the Randomization A visit and 30 days prior to booster dose at Visit 8 through Visit 9 Group 3: 30 days prior to Randomization A at Visit 6 until the Randomization A visit Group 4: 30 days prior to Randomization A at Visit 6 until the Randomization A visit Note: Participation in an observational trial or follow-up phase of a trial may be allowed; however, these instances should be discussed with this study's medical monitor (MM).
- Currently breastfeeding.
- Positive laboratory evidence of current infection with human immunodeficiency virus (HIV), hepatitis C virus (HCV) or hepatitis B virus (HBV).
- Prior receipt or anticipated use of systemic immunomodulatory or immunosuppressive medications from six months prior to Prebooster Visit through 21 days after booster dose. Note: For systemic corticosteroids, use at a dose or equivalent dose of 20 mg of prednisone daily for 14 days or more within three months of Prebooster Visit through 21 days postbooster dose is exclusionary. The use of inhaled, intranasal, topical, ocular, or intraocular steroids is allowed.
- Receipt or anticipated receipt of blood or blood-derived products from 90 days prior to Prebooster Visit through 21 days postbooster dose.
- Acute disease within the last 14 days prior to booster dose (participants with an acute mild febrile illness can be considered for a deferral of vaccination two weeks after the illness has resolved and treatment has been completed).
- Receipt or anticipated receipt of any vaccine from 30 days prior to booster dose through 21 days postbooster.
- Note: Participants that are ineligible or decline booster will be included in Group 4 (unrandomized or unboosted) for follow-up unless consent/assent for follow-up is withdrawn.
Trial locations and contacts
24 sites in 1 country.
24 sites in 1 country
United States24 sites
Velocity Clinical Research, Austin
Cedar Park, Texas, 78613
Synexus Clinical Research US, Inc.
Chicago, Illinois, 60602
Velocity Clinical Research, Cleveland
Cleveland, Ohio, 44122
Velocity Clinical Research, Providence
East Greenwich, Rhode Island, 02818
DM Clinical Research
Houston, Texas, 77081
Alliance for Multispecialty Research, LLC
Kansas City, Missouri, 64114
Wr-Crcn, Llc
Las Vegas, Nevada, 89106
Alliance for Multispecialty Research, LLC
Las Vegas, Nevada, 89119
Alliance for Multispecialty Research, LLC
Lexington, Kentucky, 40509
Velocity Clinical Research, Medford
Medford, Oregon, 97504
Optimal Research, LLC
Melbourne, Florida, 32934
Suncoast Research Associates, LLC
Miami, Florida, 33173
Alliance for Multispecialty Research, LLC
Mobile, Alabama, 36608
Alliance for Multispecialty Research, LLC
Newton, Kansas, 67114
Alliance for Multispecialty Research, LLC
Norfolk, Virginia, 23502
Lynn Institute of Norman
Norman, Oklahoma, 73072
Optimal Research, LLC
Peoria, Illinois, 61614
M3 Wake Research Inc.
Raleigh, North Carolina, 27612
Rochester Clinical Research, LLC
Rochester, New York, 14609
BFHC Research, LLC
San Antonio, Texas, 78249
Alliance for Multispecialty Research, LLC
Tempe, Arizona, 85281
DM Clinical Research
Tomball, Texas, 77375
Velocity Clinical Research, Salt Lake City
West Jordan, Utah, 84088
Alliance for Multispecialty Research, LLC
Wichita, Kansas, 67207
About this study
Official title: A Long-term Follow-up Study to Evaluate Safety and Immunogenicity of a Chikungunya Virus Virus-like Particle Vaccine (CHIKV VLP) in Healthy Adults and Adolescents After Either a Single or Booster Vaccination Dosing Regimen
The purpose of this phase 3 multicenter, randomized, double-blind, placebo-controlled rollover study is to evaluate the safety and long-term immunogenicity of CHIKV VLP vaccine in adult and adolescent participants and to evaluate CHIKV VLP booster vaccine induced serum neutralizing antibody (SNA) response at 3 or 4 years post-initial CHIKV VLP vaccination.
Read the detailed description
Primary Objectives:
- To evaluate the long-term immunogenicity of CHIKV VLP vaccine in healthy adult and adolescent participants as measured by proportion of participants maintaining an anti-CHIKV serum neutralizing antibody (SNA) titer ≥100 (seroresponse rate, also considered the presumptive seroprotection rate) at yearly intervals up to 5 years postvaccination in feeder studies EBSI-CV-317-004 (NCT05072080) and EBSI-CV-317-005 (NCT05349617).
- To assess the vaccine-induced SNA titers by a booster dose of CHIKV VLP vaccine at 3 or 4 years post-initial vaccination in feeder studies EBSI-CV- 317-004 and EBSI-CV-317-005.
- To evaluate the safety and tolerability of CHIKV VLP vaccine in all participants.
- To evaluate the safety and tolerability of a booster vaccination and compare with safety and tolerability reported post-initial vaccination of CHIKV VLP vaccine under feeder studies EBSI-CV-317-004 and EBSI-CV-317-005 in healthy adults and adolescents.
Secondary Objectives:
- To evaluate the long-term immunogenicity of CHIKV VLP vaccine in healthy adult and adolescent participants as measured by anti-CHIKV SNA geometric mean titers (GMTs) at yearly intervals up to 5 years post-initial vaccination in feeder studies EBSI-CV-317-004 and EBSI-CV-317-005.
- To evaluate the immune response to a booster vaccination and compare this response to that reported post-initial vaccination of CHIKV VLP vaccine under feeder studies EBSI-CV-317-004 and EBSI-CV-317-005 in healthy adults and adolescents.
- Conditions
- Chikungunya Virus Infection
- Being tested
- CHIKV VLP vaccine booster, Placebo booster
- Keywords
- Chikungunya, PXVX0317, Vaccine, Immunogenicity, CHIKV VLP, VIMKUNYA®
- Medical subject headings
- Chikungunya Fever
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CHIKV VLP vaccine boosterBiological
Also called PXVX0317, VIMKUNYA ®
CHIKV VLP vaccine is comprised of chikungunya virus virus-like particles (CHIKV VLP) 40 µg, aluminum hydroxide 2% adjuvant, and formulation buffer supplied as a single dose of 0.8 mL in a pre-filled syringe, to be administered via intramuscular (IM) injection in the deltoid muscle.
Placebo boosterBiological
Placebo is comprised of formulation buffer supplied as a single dose of 0.8 mL in a pre-filled syringe administered via IM injection in the deltoid muscle.
| Study group | Role | What they receive |
|---|---|---|
| Group 1a | Active comparator | CHIKV VLP vaccine booster, 3 years post initial vaccination Receives: Biological: CHIKV VLP vaccine booster |
| Group 1b | Placebo comparator | Placebo booster, 3 years post initial vaccination Receives: Biological: Placebo booster |
| Group 2a | Active comparator | CHIKV VLP vaccine booster, 4 years post initial vaccination Receives: Biological: CHIKV VLP vaccine booster |
| Group 2b | Placebo comparator | Placebo booster, 4 years post initial vaccination Receives: Biological: Placebo booster |
| Group 3 | No intervention | Up to protocol-defined unboosted participants |
| Group 4 | No intervention | All other unrandomized or unboosted participants, for any reason |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of participants maintaining a preboost anti-CHIKV SNA titer ≥100 at yearly intervals up to 5 years post-initial vaccination
For all groups using the immunogenicity evaluable population (IEP) the proportion of participants maintaining a preboost anti-CHIKV SNA titer ≥100 (seroresponse rate, also considered the presumptive seroprotection rate) at yearly intervals up to 5 years post-initial vaccination in one of the feeder studies; only prebooster data will be summarized.
Measured: 5 years post-initial vaccination in feeder study EBSI-CV-317-004 or EBSI-CV317-005 until booster
Proportion of vaccine boosted participants with composite booster response at 21 days after booster vaccination
For IEP participants who receive a CHIKV VLP vaccine booster (Groups 1a and 2a), proportion of participants with a boost response is defined as a composite of:
- ≥4-fold rise in anti-CHIKV SNA titer from prebooster to postbooster measured at 21 days after booster for participants with a prebooster titer ≥100 OR
- Anti-CHIKV SNA titer ≥100 and ≥4-fold increase in anti-CHIKV SNA titer from prebooster to postbooster measured at 21 days after booster vaccination for participants with a prebooster titer <100.
Note: Prebooster is the last SNA sample prior to booster dose, ideally the sample on boost day prior to booster dose administration but can be the time point prior if the boost day sample is missed or incorrectly processed.
Measured: 21 days after booster vaccination
Secondary outcomes (4)
Anti-CHIKV SNA Geometric Mean Titers (GMTs) at yearly intervals
For all groups using the IEP, anti-CHIKV SNA GMTs preboost at yearly intervals up to 5 years post-initial CHIKV VLP vaccination in feeder study EBSI-CV-317-004 or EBSI-CV-317-005; only prebooster data will be summarized.
Measured: 5 years post-initial vaccination in feeder study EBSI-CV-317-004 or EBSI-CV-317-005 until booster
Anti-CHIKV SNA GMTs at 21 days postboost
Anti-CHIKV SNA GMTs in Groups 1a and 2a (CHIKV VLP IEP booster population), at 21 days postboost.
Measured: 21 days postboost for Groups 1a and 2a
Anti-CHIKV SNA Geometric Mean Fold Increase (GMFI) Prebooster to Postbooster
For IEP participants who receive a CHIKV VLP vaccine booster (Groups 1a and 2a) and have a 21-day postbooster SNA titer, GMFI from prebooster anti-CHIKV SNA titer to 21 days postbooster anti-CHIKV SNA titer and at yearly intervals up to 5 years post-initial vaccination in feeder study EBSI-CV-317-004 or EBSI-CV-317-005.
Measured: 21 days after booster vaccination and 5 years post-initial vaccination in feeder study EBSI-CV-317-004 or EBSI-CV-317-005
Booster Response at 21 Days Relative to 21-day Response in Feeder Study EBSI-CV-317-004 or EBSI-CV-317-005
For IEP participants who receive a CHIKV VLP vaccine booster (Groups 1a and 2a) and have a 21-day postboost SNA titer, GMFI from feeder study EBSI-CV-317-004 or EBSI-CV-317-005 Day 22 SNA titer to 21-day postbooster SNA titer in the rollover study.
Measured: 21 days after booster vaccination
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Aug 2023
- Study start30 Aug 2023
- Primary completionFeb 2028 (estimated)
- Study completionFeb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Chikungunya Virus InfectionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- All eligible participants in the youngest (12 to \<18 years) and oldest (≥65 years) age groups will be assigned to a booster at Year 3 (Group 1). All other participants will be randomized 1:1:1 to a booster at Year 3 (Group 1) or Year 4 (Group 2), or no booster, with follow-up through the Year 5 durability timepoint (Group 3). Prior to booster dose administration (Group 1 and Group 2 only) participants will be randomized 1:1 to CHIKV VLP vaccine booster or placebo booster.
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 715 participants (actual)
Sponsor and investigators
- Lead sponsor
- Bavarian Nordic
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06007183
- Sponsor's protocol ID
- EBSI-CV-317-008
- Status last verified
- Aug 2026
- First submitted
- 18 Aug 2023
- Last updated
- 7 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Publications
Bennett SR, McCarty JM, Ramanathan R, Mendy J, Richardson JS, Smith J, Alexander J, Ledgerwood JE, de Lame PA, Royalty Tredo S, Warfield KL, Bedell L. Safety and immunogenicity of PXVX0317, an aluminium hydroxide-adjuvanted chikungunya virus-like particle vaccine: a randomised, double-blind, parallel-group, phase 2 trial. Lancet Infect Dis. 2022 Sep;22(9):1343-1355. doi: 10.1016/S1473-3099(22)00226-2. Epub 2022 Jun 13.
PubMed 35709798McCarty JM, Bedell L, Mendy J, Coates EE, Chen GL, Ledgerwood JE, Tredo SR, Warfield KL, Richardson JS. Chikungunya virus virus-like particle vaccine is well tolerated and immunogenic in chikungunya seropositive individuals. Vaccine. 2023 Oct 6;41(42):6146-6149. doi: 10.1016/j.vaccine.2023.08.086. Epub 2023 Sep 9.
PubMed 37690874Richardson JS, Anderson DM, Mendy J, Tindale LC, Muhammad S, Loreth T, Tredo SR, Warfield KL, Ramanathan R, Caso JT, Jenkins VA, Ajiboye P, Bedell L; EBSI-CV-317-004 Study Group. Chikungunya virus virus-like particle vaccine safety and immunogenicity in adolescents and adults in the USA: a phase 3, randomised, double-blind, placebo-controlled trial. Lancet. 2025 Apr 19;405(10487):1343-1352. doi: 10.1016/S0140-6736(25)00345-9. Epub 2025 Mar 27.
PubMed 40158526Tindale LC, Richardson JS, Anderson DM, Mendy J, Muhammad S, Loreth T, Tredo SR, Ramanathan R, Jenkins VA, Bedell L, Ajiboye P; EBSI-CV-317-005 Study Group. Chikungunya virus virus-like particle vaccine safety and immunogenicity in adults older than 65 years: a phase 3, randomised, double-blind, placebo-controlled trial. Lancet. 2025 Apr 19;405(10487):1353-1361. doi: 10.1016/S0140-6736(25)00372-1. Epub 2025 Mar 27.
PubMed 40158524