Pfizer, Valneva overcome CRO issues to finish phase 3 recruitment for Lyme disease vaccine

Pfizer and Valneva have completed recruitment for a phase 3 trial of the Lyme disease vaccine VLA15 after work was halted earlier this year due to problems with one of the CROs at some of the trial sites.

In February, the two companies were forced to pull half of the participants from the study after the discovery of good clinical practice violations at some sites in the U.S. that were run by third-party trial operator Care Access. The problems caused the two to push back a regulatory filing for the vaccine.

In the meantime, other sites not operated by Care Access continued to enroll patients to make up for the shortfall and have signed on 9,437 participants, the two companies said in a Nov. 4 press release.

Lyme disease is a vector-borne illness most commonly found in the Northern Hemisphere and affects an estimated 476,000 people in the U.S. each year and an estimated 129,000 people in Europe, according to the companies. The disease can lead to long-lasting consequences, Annaliesa Anderson, SVP and head of  Pfizer’s vaccine research and development, said in the release.

“If approved, a vaccine could prevent the disease and ease the burden of acute, severe and sometimes persistent consequences in both adults and children," Anderson said. 

The VLA15 trials began in August 2022 with an overall enrollment goal of 18,000 healthy people who live in areas with endemic Lyme disease and lead lifestyles that put them at increased risk of being bitten by ticks. Pfizer expects to submit regulatory filings in the U.S. and Europe in 2026.