Turn on cookies to sign in
Signing in saves your progress to your Curie account. We can only do that with cookies on — turn them on to continue.
A phase 3 trial of LB6V, a Lyme disease vaccine co-funded by Pfizer and Valneva, showed over 70% efficacy — but narrowly missed its primary endpoint. Researchers attribute the miss to a low number of confirmed cases. Despite the stumble, Pfizer still plans to seek regulatory approval, with a potential U.S. and European launch targeted for late 2027.
So close, yet so far. A phase 3 trial of LB6V — a Lyme disease vaccine candidate co-developed by Pfizer and Valneva — showed strong efficacy against the most common Lyme-causing bacteria, but narrowly missed its primary statistical endpoint. Researchers presented the results at IDWeek in Washington, calling the vaccine's performance "clinically meaningful" even as the numbers fell just short of the bar.
The trial enrolled nearly 10,000 participants aged 5 and older, with 8,011 completing the study. Participants received four doses of the six-valent OspA-based vaccine over roughly 18 months. Despite the endpoint miss, Pfizer has said it will pursue regulatory approval, with a potential launch in U.S. and European markets targeted for the second half of 2027.
By the Numbers:
Why it matters: There has been no commercially available Lyme disease vaccine since LYMErix was pulled in 2002. With cases surging, LB6V could fill a critical gap — if regulators find the efficacy data compelling enough.
