Pfizer and Valneva's experimental Lyme vaccine (LB6V/PF-07307405) demonstrated 73.2% efficacy 28 days after the final dose but failed to meet the primary endpoint when the 95% confidence interval lower bound was only 15.8%, below the required 20% threshold1
The vaccine showed 74.8% efficacy one day after the fourth dose, with the confidence interval lower bound exceeding 20% in this secondary pre-specified analysis12
The companies blamed the primary endpoint miss on fewer than anticipated Lyme disease cases being accrued during the VALOR study, which enrolled 9,437 individuals aged 5 years and older across the U.S., Canada, and Europe1
Despite missing the primary endpoint, Pfizer stated it is confident in the vaccine's potential and plans to submit it to regulatory authorities for approval1
Lyme disease affects approximately 476,000 people annually in the U.S. and 129,000 in Europe, with no vaccines currently approved in the U.S.; GSK withdrew its Lyme vaccine (LYMERix) in 2002 due to poor sales12
Under their 2020 partnership agreement, Valneva received $130 million upfront and is eligible for up to $308 million in total cash payments, with Pfizer maintaining sole control over commercialization12
Sources:
1. https://www.fiercebiotech.com/biotech/pfizer-valneva-blame-low-lyme-cases-phase-3-vaccine-fail-still-plan-approval-push
2. https://www.biospace.com/drug-development/pfizer-confident-in-valneva-partnered-lyme-vaccine-despite-missed-primary-endpoint