Valneva SE (Nasdaq: VALN; Euronext Paris: VLA), a specialty vaccine company, and Pfizer Inc. (NYSE: PFE) today reported further positive Phase 2 data for their Lyme disease vaccine candidate, VLA15. Based on these new results, Valneva and Pfizer plan to proceed with a three-dose primary series vaccination schedule in a planned Phase 3 clinical trial. The trial will evaluate VLA15 in adults and pediatric subjects 5 years of age and above and is expected to be initiated in 2022, subject to regulatory approval.

The Phase 2 trial, VLA15-221, compared the immunogenicity of VLA15 after administration of two (at months 0 and 6) or three (at months 0, 2 and 6) primary series doses in groups aged 5-11, 12-17 and 18-65 years. In the sub-analysis of adult participants (18-65 years old) who received VLA15 in either the two-dose schedule (N=90) or the three-dose schedule (N=97), performed one month after the last vaccination dose, VLA15 was found to be immunogenic with both vaccination schedules tested. These data are consistent with the strong immunogenicity profile observed for this age group in previous Phase 2 studies. However, the induction of anti-OspA IgG (anti-outer surface protein A immunoglobulin G) antibody titers was higher in participants who received the three-dose primary series compared to those who received the two-dose primary series, supporting the use of a three-dose primary series schedule in the planned Phase 3 clinical trial. The VLA15-221 trial is ongoing to assess the safety and immunogenicity of VLA15 in 5-17 year olds. Initial pediatric data are expected in the first half of 2022.

The analysis was also consistent with the acceptable safety and tolerability profile observed in previous studies of VLA15. No vaccine-related serious adverse events (SAEs) were observed.

Juan Carlos Jaramillo M.D., Chief Medical Officer of Valneva, said, "I'm very pleased with these results, which are critical for determining the optimal vaccination schedule for our planned Phase 3 trial. In partnership with Pfizer, we are excited to further investigate this vaccine candidate, which will hopefully help provide protection against Lyme disease for both adults and children."

Kathrin U. Jansen, Ph.D., Senior Vice President and Head of Vaccine Research & Development at Pfizer, said: "Lyme disease is increasingly impacting people throughout the northern hemisphere, potentially due to environmental changes and more active outdoor lifestyles. The continued positive data from the VLA15-221 trial support the ongoing development of this vaccine candidate, and we look forward to continuing to work with Valneva to potentially help protect people against Lyme disease."

About VLA15

VLA15 is the only Lyme disease vaccine candidate currently in clinical development. This investigational multivalent protein subunit vaccine uses an established mechanism of action for a Lyme disease vaccine that targets the outer surface protein A (OspA) of Borrelia burgdorferi, the bacteria that cause Lyme disease. OspA is one of the most dominant surface proteins expressed by the bacteria when present in a tick. The vaccine covers the six OspA serotypes expressed by Borrelia burgdorferi sensu lato species that are prevalent in North America and Europe. VLA15 has demonstrated strong immunogenicity and safety data in pre-clinical and clinical studies so far. The program was granted Fast Track designation by the U.S. Food and Drug Administration (FDA) in July 2017(1). Valneva and Pfizer entered into a collaboration agreement in April 2020 to co-develop VLA15.(2)

About Clinical Study VLA15-221

VLA15-221 is a randomized, observer-blind, placebo-controlled Phase 2 study. It is the first clinical study with VLA15 that enrolls a pediatric population aged 5 years and older.

294 healthy adult participants received VLA15 at two different immunization schedules (month 0-2-6 [N=97] or month 0-6 [N=90]) or three doses of placebo (month 0-2-6 [N=107]). Vaccine recipients received VLA15 at a dose of 180 μg, which was selected based on data generated in the two previous Phase 2 studies. The main safety and immunogenicity readout in adults was performed at month 7. A subset of participants will receive a booster dose of VLA15 or placebo at month 18 (booster phase) and will be followed for three additional years to monitor antibody persistence. The VLA15-221 trial is ongoing to assess the safety and immunogenicity of VLA15 in a pediatric population aged 5 years and above.

VLA15 is tested as an alum-adjuvanted formulation and administered intramuscularly. The study is conducted at sites located in areas where Lyme disease is endemic and has enrolled volunteers with a cleared past infection with Borrelia burgdorferi as well as Borrelia burgdorferi-na?ve volunteers.

About Lyme Disease

Lyme disease is a systemic infection caused by Borrelia burgdorferi bacteria transmitted to humans by infected Ixodes ticks(3). It is considered the most common vector-borne illness in the Northern Hemisphere. While the true incidence of Lyme disease is unknown, it is estimated to annually affect approximately 476,000 people in the United States(4) and 130,000 people in Europe(5). Early symptoms of Lyme disease (such as a gradually expanding erythematous rash called Erythema migrans or more unspecific symptoms like fatigue, fever, headache, mild stiff neck, arthralgia or myalgia) are often overlooked or misinterpreted. Left untreated, the disease can disseminate and cause more serious complications affecting the joints (arthritis), the heart (carditis) or the nervous system. The medical need for vaccination against Lyme disease is steadily increasing as the disease footprint widens(6).

About Valneva SE

Valneva is a specialty vaccine company focused on the development and commercialization of prophylactic vaccines for infectious diseases with significant unmet medical need. The Company takes a highly specialized and targeted approach to vaccine development and then applies its deep understanding of vaccine science to develop prophylactic vaccines addressing these diseases. Valneva has leveraged its expertise and capabilities both to successfully commercialize two vaccines and to rapidly advance a broad range of vaccine candidates into and through the clinic, including candidates against Lyme disease, the chikungunya virus and COVID-19.

About Pfizer: Breakthroughs That Change Patients' Lives

At Pfizer, we apply science and our global resources to bring therapies to people that extend and significantly improve their lives. We strive to set the standard for quality, safety and value in the discovery, development and manufacture of health care products, including innovative medicines and vaccines. Every day, Pfizer colleagues work across developed and emerging markets to advance wellness, prevention, treatments and cures that challenge the most feared diseases of our time. Consistent with our responsibility as one of the world's premier innovative biopharmaceutical companies, we collaborate with health care providers, governments and local communities to support and expand access to reliable, affordable health care around the world. For more than 170 years, we have worked to make a difference for all who rely on us.

1. Valneva Receives FDA Fast Track Designation for its Lyme Disease Vaccine Candidate VLA15
2. Valneva and Pfizer Announce Collaboration to Co-Develop and Commercialize Lyme Disease Vaccine, VLA15
3. Stanek et al. 2012, The Lancet 379:461-473
4. Source: https://www.cdc.gov/lyme/stats/humancases.html
5. Sykes RA, et al. An estimate of Lyme borreliosis incidence in Western Europe. Journal of Public Health 2017; 39(1): 74-81
6. New Scientist, Lyme disease is set to explode and we still don’t have a vaccine; March 29, 2017. https://www.newscientist.com/article/mg23431195-800-lyme-disease-is-set-to-explode-and-you-cant-protect-yourself/