Pfizer Says Lyme Vaccine Missed Trial Target, Will Still Seek Approval

‘These results bring us a step closer to our goal of delivering a much-needed vaccine to help protect against Lyme disease,’ an executive said.

A blacklegged tick, also known as a deer tick, a carrier of Lyme disease. CDC via AP

Pfizer and its partner Valneva said on March 23 that their experimental Lyme disease vaccine did not meet the target in a clinical trial, but the results were strong enough that the firms will seek regulatory approval for the shot.

The vaccine, known as LB6V, was about 75 percent efficacious in reducing confirmed Lyme in recipients, compared with placebo recipients, the companies said. The efficacy was measured one day after the fourth vaccine dose, and was similar to the 73 percent efficacy observed 28 days after the fourth shot.