NEW YORK and LYON, France, August 14, 2026
Pfizer Inc. and Valneva SE announced that the European Medicines Agency (EMA) has validated their Marketing Authorization Application (MAA) for PF-07307405, an investigational 6-valent OspA-based Lyme disease vaccine candidate. EMA validation confirms that the application is sufficiently complete to begin the formal regulatory assessment process. The submission is supported by favorable results from the Phase 3 VALOR trial, which evaluated the vaccine candidate in children and adults aged five years and older. The companies reported more than 70% vaccine efficacy and said no safety concerns were identified in the study. If approved, PF-07307405 could become an important new preventive option for Lyme disease in Europe, where the infection represents a significant and growing public health burden.
PF-07307405 Shows More Than 70% Efficacy in Phase 3 VALOR
The EMA submission is based on results from the multinational Phase 3 VALOR trial, a randomized, placebo-controlled and observer-blinded study conducted across Lyme disease endemic regions in the United States, Canada and Europe. The trial enrolled 9,437 participants aged five years and older, who were randomized to receive either PF-07307405 or saline placebo. Participants received four doses, with vaccination administered at months 0, 2 and 5-9, followed by a fourth dose approximately one year later before the next Lyme disease season. The companies reported more than 70% efficacy against Lyme disease in the Phase 3 program and described the vaccine candidate as well tolerated, with no safety concerns identified. The results support continued regulatory evaluation, although EMA validation is not an approval and the final benefit-risk assessment remains to be completed. The candidate is currently investigational and there are no approved human Lyme disease vaccines in Europe or elsewhere.
OspA Vaccine Designed to Block Lyme Disease Transmission
PF-07307405 uses a 6-valent outer surface protein A (OspA) approach targeting six prevalent OspA serotypes associated with Borrelia burgdorferi sensu lato in North America and Europe. Rather than directly targeting the bacterium after it enters the human body, the vaccine is designed to generate antibodies that act within the feeding tick. When an infected tick feeds on a vaccinated person, vaccine-induced antibodies can enter the tick with the blood meal and bind to OspA proteins on Borrelia, potentially preventing the bacteria from leaving the tick and being transmitted to the person. Lyme disease is transmitted primarily through infected Ixodes ticks and can initially cause symptoms including fever, fatigue, headache and erythema migrans. If untreated, infection can spread and lead to complications involving the joints, heart, nervous system and skin. The companies said the vaccine could provide an additional layer of protection as the geographic footprint of Lyme disease continues to expand.
Advertisement
EMA Review Marks Major Milestone for Pfizer and Valneva
The regulatory milestone follows a collaboration and license agreement established between Pfizer and Valneva in 2020 for the co-development of PF-07307405, with Pfizer holding exclusive manufacturing and commercialization rights subject to regulatory success. The candidate has now completed two pivotal Phase 3 trials, making it one of the most advanced human Lyme disease vaccine programs in development. The companies said Lyme disease affects more than 100,000 people annually in Europe, while more than 200 million people live in areas considered at risk. The EMA assessment will now determine whether the available clinical, manufacturing and safety evidence supports marketing authorization. The next major milestone will be the EMA’s regulatory decision, rather than the current validation itself. If the application ultimately receives approval, PF-07307405 could represent a significant advancement in Lyme disease prevention and establish a new vaccine option for populations living in or traveling to endemic areas.
Source: Pfizer, Valneva ,press release
