Lyme Disease Vaccine Candidate Phase 3 Trial to Begin

Summer in the Northeast is vacation season, when city dwellers flee the heat in search of cooler climes. Increasingly, it’s also the season for Lyme disease, a tick-borne illness that afflicts an estimated 476,000 people in the U.S.[1] and another 130,000 in Europe each year.[2] Children aged 5-14 years old have historically represented the largest share of confirmed cases, according to CDC data.[3]

Pfizer and its partner Valneva SE, a specialty vaccine company, announced the initiation of a Phase 3 clinical study of their investigational Lyme disease candidate vaccine, VLA15. The Phase 3 study is planned to enroll approximately 6,000 participants 5 years of age and older in Europe and the U.S.

“With increasing global rates of Lyme disease, providing a new option for people to help protect themselves from the disease is more important than ever,” said Annaliesa Anderson, Ph.D., Senior Vice President and Head of Vaccine Research & Development at Pfizer. “We hope that the data generated from the Phase 3 study will further support the positive evidence for VLA15 to date, and we are looking forward to collaborating with the research sites across the U.S. and Europe on this important trial.”[4]

The only Lyme disease vaccine candidate in clinical development

Lyme disease is caused by bacteria that is transmitted to humans by certain deer ticks. Early symptoms can include an expanding rash, fatigue, fever and headache. Untreated, the disease can cause serious complications affecting the joints, heart and nervous system. VLA15 is the only Lyme disease vaccine candidate currently in clinical development.

If successful, the vaccine candidate will block an outer surface protein of the bacteria that causes Lyme disease and help inhibit the bacterium’s ability to leave the tick and infect humans.

Pfizer could potentially submit a Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) and Marketing Authorisation Application (MAA) to the European Medicines Agency (EMA) as early as 2025, if the planned Phase 3 study is successfully completed.

An ongoing effort

Pfizer has a rich history in vaccine research and development and deep-rooted knowledge of infectious diseases. Over the years, the company has played a pivotal role in eliminating or nearly eliminating deadly infectious diseases like smallpox and polio globally and has successfully designed novel vaccines based on new delivery systems and technologies that have resulted in vaccines to prevent bacterial infections. Pfizer’s Vaccine Research and Development scientists continue to work on vaccines against major infectious diseases while striving to bring the benefits of vaccines into previously unexplored areas. The company is at the forefront to usher in a new era of vaccine innovation, both to prevent and treat disease, with special focus on maternal/neonatal, hospital-acquired infections (HAI), and cancer.

For more information on our vaccine research efforts, visit our website here: Vaccine and Immunization Research and Development News | Pfizer

[1] How many people get Lyme disease? CDC data available here.
[2] Sykes RA, et al. An estimate of Lyme borreliosis incidence in Western Europe. Journal of Public Health 2017; 39(1): 74-81
[3] Lyme disease – Confirmed cases by age and sex. CDC data available here.
[4] Pfizer and Valneva Initiate Phase 3 Study of Lyme Disease Vaccine Candidate VLA15. Available here.

Forward-looking statements included herein are subject to substantial risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. We encourage you to read our reports filed with the U.S. Securities and Exchange Commission (SEC), including the sections captioned “Risk Factors” and “Forward Looking Information and Factors that May Affect Future Results,” for a description of such substantial risks and uncertainties. These reports are available at and the SEC’s website.

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