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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT05634811
Recruitment Status : Active, not recruiting
First Posted : December 2, 2022
Last Update Posted : March 5, 2024
Information provided by (Responsible Party):

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.

Condition or disease Intervention/treatment Phase
Lyme Disease Biological: VLA15 Other: Normal Saline Phase 3

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 3242 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Other
Actual Study Start Date : December 12, 2022
Estimated Primary Completion Date : June 6, 2025
Estimated Study Completion Date : June 6, 2025

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: VLA15
Participants will receive 6-valent OspA-based Lyme disease vaccine (VLA15).
Biological: VLA15
6-valent OspA-based Lyme disease vaccine
Other Name: PF-07307405

Placebo Comparator: Normal Saline (Placebo)
Participants will receive 0.9% sodium chloride solution for injection
Other: Normal Saline
0.9% sodium chloride solution for injection

Primary Outcome Measures :
  1. The percentage of participants reporting prompted local reactions [ Time Frame: Within 7 days following each study intervention administration ]
  2. The percentage of participants reporting prompted systemic events [ Time Frame: Within 7 days following each study intervention administration ]
  3. The percentage of participants reporting adverse events (AEs) [ Time Frame: Through 1 month following each study intervention administration ]
  4. The percentage of participants reporting newly diagnosed chronic medical conditions (NDCMCs) [ Time Frame: Through study completion, up to 24 months ]
  5. The percentage of participants reporting serious adverse events (SAEs) [ Time Frame: Through study completion, up to 24 months ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   5 Years to 17 Years   (Child)
Sexes Eligible for Study:   All
Accepts 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.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT05634811

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Sponsors and Collaborators
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Study Director: Pfizer Call Center Pfizer
Additional Information:
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Responsible Party: Pfizer Identifier: NCT05634811    
Other Study ID Numbers: C4601012
First Posted: December 2, 2022    Key Record Dates
Last Update Posted: March 5, 2024
Last Verified: March 2024
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at:

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Pfizer:
Borrelia burgdorferi
Vector-Borne Disease
Lyme Disease Vaccine
Outer Surface Protein A (OspA)
Additional relevant MeSH terms:
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Lyme Disease
Gram-Negative Bacterial Infections
Bacterial Infections
Bacterial Infections and Mycoses
Borrelia Infections
Spirochaetales Infections
Tick-Borne Diseases
Vector Borne Diseases