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Safety Study of a Vaccine to Help Protect Against Lyme Disease in Healthy Children

A PHASE 3, RANDOMIZED, PLACEBO-CONTROLLED, OBSERVER-BLINDED TRIAL TO EVALUATE THE SAFETY OF A 6-VALENT OspA-BASED LYME DISEASE VACCINE (VLA15) IN HEALTHY CHILDREN 5 THROUGH 17 YEARS OF AGE

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05634811
Enrollment
3547
Registered
2022-12-02
Start date
2022-12-12
Completion date
2025-07-21
Last updated
2026-05-07

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

Conditions

Lyme Disease

Keywords

Borreliosis, Borrelia burgdorferi, Spirochetes, Vector-Borne Disease, Lyme Disease Vaccine, VLA15, Outer Surface Protein A (OspA), Ticks

Brief summary

This study is to understand if the study vaccine (called VLA15) is safe in healthy children. We are looking for children who: * are healthy * are age 5 through 17 * have not been diagnosed with any form of Lyme disease in the past * have not received any vaccines for Lyme disease in the past Lyme disease happens most often in children of this age. The study vaccine may be used potentially to help prevent Lyme disease. The goal of this study is to get more information about the safety of the study vaccine in this age group. Participants will be in this study for about 2 years. During that time, they will receive VLA15 or placebo (sterile saltwater solution) by a "shot" in the arm. We will compare experience of children receiving VLA15 to those receiving the placebo. Participants will not know whether they get VLA15 or placebo. Everyone participating in this study will: * get the shots in a clinic or in a hospital office * receive a total of 4 shots * receive the first 3 shots within 6 months * receive the last shot about 1 year afterwards * need to come to the trial site for 6 planned visits; 4 of these are vaccination visits and 2 are follow-up visits. We will contact you by phone 1 time every year during the study to monitor your experience. You may have extra visits if you experience a severe reaction after a vaccine dose.

Interventions

BIOLOGICALVLA15

6-valent OspA-based Lyme disease vaccine

OTHERNormal Saline

0.9% sodium chloride solution for injection

Sponsors

Pfizer
Lead SponsorINDUSTRY

Study design

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

Eligibility

Sex/Gender
ALL
Age
5 Years to 17 Years
Healthy volunteers
Yes

Inclusion criteria

* Healthy participants at enrollment who are determined to be eligible for inclusion in the study. Participants with preexisting chronic medical conditions determined to be stable may be included. * Participants and/or participants' parent(s)/guardian who are willing and able to comply with all scheduled visits, study procedures and lifestyle considerations for the duration of the study.

Exclusion criteria

* Female participants that are pregnant, breastfeeding, or have a positive urine pregnancy test at Visit 1. Sexually active females and fertile males unwilling to use contraception as per protocol. * Any contraindication to vaccination or vaccine components, including previous anaphylactic reaction to any vaccine or vaccine-related components. * Any diagnosis of Lyme disease within the past 3 months. * Any history of Lyme arthritis, carditis, neuroborreliosis, or other disseminated Lyme Disease (LD), regardless of when diagnosed. * Known tick bite within the past 4 weeks. * Congenital or acquired immunodeficiency or other conditions or treatments associated with immunosuppression that would inhibit the ability to mount an immune response to a vaccine. * Other medical, psychiatric condition, active suicidal ideation/behavior or lab abnormality which increases risk of study participation or, in investigator's judgment is inappropriate for the study. * Receipt of a previous vaccination for LD. * Treatment for LD in the 3 months prior to study intervention administration. * Receipt of blood/plasma products or immunoglobulins within 6 months before study intervention administration through conclusion of the study. * Receipt of systemic corticosteroids for ≥14 days within 28 days before study intervention administration. Inhaled/nebulized, intra-articular, intrabursal, or topical corticosteroids are permitted. * Receipt of chronic systemic treatment with other known immunosuppressant medications, or radiotherapy, within 6 months before study intervention administration. * Current use of any prohibited concomitant medication(s) or participants unwilling/unable to use a permitted concomitant medication(s). * Participation in other studies involving investigational drugs/vaccines/devices within 28 days prior to study entry and/or during study participation (observational studies are acceptable). * Investigator site staff, sponsor/sponsor delegates directly involved in the conduct of the study and their family members; site staff supervised by the investigator and their family members.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 1From Day 1 through 1 Month after Study Vaccination 1 (Vaccination on Day 1, Month 0)An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Only AEs collected by non-systematic assessment (excluding local reactions and systematic events) after dose 1 were included in this outcome measure. AEs included both serious AEs (SAEs) and non-SAEs.
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 2From Day 1 through 1 Month after Study Vaccination 2 (Vaccination on Day 1, Month 2)An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Only AEs collected by non-systematic assessment (excluding local reactions and systematic events) after dose 2 were included in this outcome measure. AEs included both SAEs and non-SAEs.
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 3From Day 1 through 1 Month after Study Vaccination 3 (Vaccination on Day 1, Month 6)An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Only AEs collected by non-systematic assessment (excluding local reactions and systematic events) after dose 3 were included in this outcome measure. AEs included both SAEs and non-SAEs.
Percentage of Participants With AEs Through 1 Month Following Study Vaccination 4 (Booster Dose)From Day 1 through 1 Month after Study Vaccination 4 (Vaccination on Day 1, Month 18)An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Only AEs collected by non-systematic assessment (excluding local reactions and systematic events) after dose 4 were included in this outcome measure. AEs included both SAEs and non-SAEs.
Percentage of Participants With AEs Through 1 Month Following Any Study VaccinationFrom Day 1 through 1 Month after any study vaccinationAn AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Only AEs collected by non-systematic assessment (excluding local reactions and systematic events) after any dose were included in this outcome measure.
Percentage of Participants With Newly Diagnosed Chronic Medical Condition (NDCMCs) Throughout the StudyThroughout the study (from study vaccination 1 through 6 months post study Vaccination 4 [Booster dose]: maximum up to 24 months)An NDCMC was defined as a disease or medical condition, not previously identified, that was expected to be persistent or was otherwise long-lasting in its effects. NDCMCs included conditions that were undiagnosed prior to study entry (diagnosed while in the study and confirmed not to be a preexisting condition) and that were not considered temporary conditions based upon the expected natural history of the condition. An NDCMC was not reported on AE CRF.
Percentage of Participants With Serious Adverse Events (SAEs) Throughout the StudyThroughout the study (from study vaccination 1 through 6 months post study Vaccination 4 [Booster dose]: maximum up to 24 months)An SAE was defined as any untoward medical occurrence that, at any dose, met one or more of the following criteria: resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, any other important medical event.
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 1From Day 1 through Day 7 after Study Vaccination 1 (Vaccination on Day 1, Month 0)Local reactions included pain at injection site, redness and swelling and were recorded by participants in the electronic dairy (e-diary) or by investigators in case report form (CRF) after vaccination. Local reactions were graded per the 'Local Reaction Grading Scale' per protocol based on Center for Biologics Evaluation and Research (CBER) toxicity guidelines. Percentage of participants with at least 1 local reaction of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 2From Day 1 through Day 7 after Study Vaccination 2 (Vaccination on Day 1, Month 2)Local reactions included pain at injection site, redness and swelling and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Local reactions were graded per the 'Local Reaction Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 local reaction of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 3From Day 1 through Day 7 after Study Vaccination 3 (Vaccination on Day 1, Month 6)Local reactions included pain at injection site, redness and swelling and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Local reactions were graded per the 'Local Reaction Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 local reaction of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days Following Study Vaccination 4 (Booster Dose)From Day 1 through Day 7 after Study Vaccination 4 (Vaccination on Day 1, Month 18)Local reactions included pain at injection site, redness and swelling and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Local reactions were graded per the 'Local Reaction Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 local reaction of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Local Reaction of Any Grade for up to 7 Days After Any Study VaccinationFrom Day 1 through Day 7 after any study vaccinationLocal reactions included pain at injection site, redness and swelling and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Local reactions were graded per the 'Local Reaction Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 local reaction of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 1From Day 1 through Day 7 after Study Vaccination 1 (Vaccination on Day 1, Month 0)Systemic events included fever, fatigue, headache, muscle pain and joint pain and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Systemic events were graded per the 'Systemic Events Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 systemic event of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 2From Day 1 through Day 7 after Study Vaccination 2 (Vaccination on Day 1, Month 2)Systemic events included fever, fatigue, headache, muscle pain and joint pain and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Systemic events were graded per the 'Systemic Events Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 systemic event of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 3From Day 1 through Day 7 after Study Vaccination 3 (Vaccination on Day 1, Month 6)Systemic events included fever, fatigue, headache, muscle pain and joint pain and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Systemic events were graded per the 'Systemic Events Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 systemic event of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days Following Study Vaccination 4 (Booster Dose)From Day 1 through Day 7 after Study Vaccination 4 (Vaccination on Day 1, Month 18)Systemic events included fever, fatigue, headache, muscle pain and joint pain and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Systemic events were graded per the 'Systemic Events Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 systemic event of any grade were reported in this outcome measure.
Percentage of Participants With at Least 1 Systemic Event of Any Grade for up to 7 Days After Any Study VaccinationFrom Day 1 through Day 7 after any study vaccinationSystemic events included fever, fatigue, headache, muscle pain and joint pain and were recorded by participants in the e-diary or by investigators in CRF after vaccination. Systemic events were graded per the 'Systemic Events Grading Scale' per protocol based on CBER toxicity guidelines. Percentage of participants with at least 1 systemic event of any grade were reported in this outcome measure.

Countries

United States

Contacts

STUDY_DIRECTORPfizer CT.gov Call Center

Pfizer

Participant flow

Recruitment details

A total of 3646 participants were enrolled, of which 3547 participants were randomized.

Pre-assignment details

This study was conducted across 57 sites across the United States of America (USA).

Baseline characteristics

Characteristic
Age, Continuous11 Years
STANDARD_DEVIATION 3.5
Ethnicity (NIH/OMB)
Hispanic or Latino
240 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
391 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
17 Participants
Race (NIH/OMB)
American Indian or Alaska Native
9 Participants
Race (NIH/OMB)
Asian
27 Participants
Race (NIH/OMB)
Black or African American
99 Participants
Race (NIH/OMB)
More than one race
9 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
4 Participants
Race (NIH/OMB)
Unknown or Not Reported
10 Participants
Race (NIH/OMB)
White
2690 Participants
Sex: Female, Male
Female
1645 Participants
Sex: Female, Male
Male
776 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
deaths
Total, all-cause mortality
0 / 1,4290 / 4670 / 1,2191 / 4180 / 2,6481 / 885
other
Total, other adverse events
1,290 / 1,429341 / 4671,121 / 1,219295 / 4182,411 / 2,648636 / 885
serious
Total, serious adverse events
15 / 1,4294 / 46727 / 1,21910 / 41842 / 2,64814 / 885

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 8, 2026