Pfizer, Valneva Report Strong Efficacy Data From Lyme Vaccine Trial

By Megan Cheah

Pharmaceutical giant Pfizer and French vaccine maker Valneva reported positive topline results from their phase three study of a vaccine candidate for Lyme disease.

The companies said the results strengthen confidence in the vaccine candidate and that Pfizer is planning submissions to regulatory authorities.

In a statement Monday, they said that the investigational LB6V vaccine demonstrated more than 70% efficacy in preventing Lyme disease in individuals aged five and older. It was well tolerated with no safety concerns identified.

Fewer Lyme disease cases were accrued over the study period than anticipated, and the pre-determined statistical criterion wasn't met in the primary endpoint.

However, Pfizer said it is confident in the vaccine's potential, noting that this criterion was met in the second pre-specified analysis and the clinically meaningful efficacy demonstrated in the trial.

"These results bring us a step closer to our goal of delivering a much-needed vaccine to help protect against Lyme disease," said Thomas Lingelbach, chief executive and board member of Valneva.

Lyme disease is a bacterial infection that can be spread to humans by infected ticks. Early symptoms include a rash, fatigue, muscle and joint pain, headache and fever, but can often be overlooked or misinterpreted.

There is no current approved human vaccine for Lyme disease and LB6V is the furthest-advanced vaccine in development, said Pfizer and Valneva.

Write to Megan Cheah at megan.cheah@wsj.com

(END) Dow Jones Newswires

March 23, 2026 06:59 ET (10:59 GMT)