If the trial succeeds, the vaccine could be the first human vaccine for the tick-borne illness in the U.S. in 2 decades. One other vaccine – LYMErix – was used in the past but was discontinued in 2002.
“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,” Annaliesa Anderson, PhD, Pfizer’s senior vice president and head of vaccine research and development, said in the statement.
Lyme disease infects about 476,000 people in the U.S. each year, according to CDC data. About 30,000 cases are officially reported to the CDC each year by state health departments.
In the phase III trial by Pfizer and Valneva, a French biotech company, the vaccine candidate VLA15 will be tested for efficacy, safety, and immune response. The trial will enroll about 6,000 healthy adults and children, ages 5 and older.
The trial is being done at up to 50 sites in the U.S. and Europe where Lyme disease is usually found, including Finland, Germany, the Netherlands, Poland, and Sweden. People in the trial will get three doses of the vaccine or a saline placebo over a 5- to 9-month period, followed by a booster dose or saline placebo 12 months later.
The vaccine, called a protein subunit vaccine, targets the outer surface protein A of Borrelia burgdorferi, the bacteria that causes Lyme disease. The protein is expressed when present in a tick, and blocking the protein stops the bacteria from leaving the tick and infecting humans.
Data from phase II studies showed a strong immune response in adults and children, with “acceptable safety and tolerability profiles,” Pfizer said.
After the phase III study, Pfizer could submit a biologics license application to the FDA and a marketing authorization application to the European Medicines Agency in 2025.
“We are extremely pleased to reach this important milestone in the development of VLA15,” Juan Carlos Jaramillo, MD, chief medical officer of Valneva, said in the statement.
“Lyme disease continues to spread, representing a high unmet medical need that impacts the lives of many in the Northern Hemisphere,” he said. “We look forward to further investigating the VLA15 candidate in Phase 3, which will take us a step closer to potentially bringing this vaccine to both adults and children who would benefit from it.”
The trial comes as of Lyme disease appears to be more common across the U.S. Diagnoses of it rose 357% in rural areas and 65% in urban areas between 2007 and 2021, according to a recent analysis of private insurance claims released this month.
Early symptoms of Lyme disease include a rash, as well as symptoms such as fatigue, fever, headache, a stiff neck, muscle pain, and joint pain. The general symptoms can often be overlooked or confused for those of another disease.
Left untreated, Lyme disease can spread throughout the body and cause serious complications, such as arthritis, heart inflammation, and nervous system issues.