- Valneva SE (Nasdaq: VALN; Euronext Paris: VLA), a specialty vaccine company, and Pfizer Inc. (NYSE: PFE), today announced further positive Phase 2 results, including booster response, for Lyme disease vaccine candidate VLA15.
The Phase 2 study, VLA15-202, is evaluating the immunogenicity and safety of VLA15 in a Month 0-2-6 vaccination schedule. The study enrolled 246 healthy adults 18 to 65 years of age in the U.S. As announced in October 20201, the study met its primary endpoint of demonstrating that VLA15 was immunogenic across all dose groups tested and elicited high antibody responses across all serotypes (ST1 - ST6) at one month after completion of the primary vaccination series. Continued evaluation at Month 18 showed that antibody titers declined thereafter across all groups, remaining above baseline but confirming the need for a booster strategy.
VLA15 was safe and well-tolerated across all doses and age groups tested. No related Serious Adverse Events (SAEs) were observed in any treatment group.
Participants who received a complete primary vaccination series with 180 µg doses of VLA15, were invited to continue the study in a booster extension phase and were randomized to receive an additional 180 µg dose of VLA15 (N=39) or placebo (N=19) at Month 18.
VLA15's acceptable safety profile was confirmed through one-month post-booster. Administration of a booster dose elicited a strong anamnestic response yielding a 2.9-fold (ST3) to 4.2-fold (ST1, ST4) increase (Geometric Mean Fold Rise) in anti-OspA IgG antibody titers compared with titers observed after primary immunization. All participants seroconverted to anti-OspA IgG after the booster dose, meaning Seroconversion Rates (SCRs) were 100% for all OspA serotypes. SCR was defined as the rate of subjects that changed from seronegative at baseline to seropositive. Additionally, subjects who were seropositive at baseline needed to show at least a 4-fold increase in anti-OspA IgG compared to baseline titer. Functionality of elicited antibodies was demonstrated by Serum Bactericidal activity Assays, leading to SCRs ranging from 86.8% (ST2) to 100.0% (ST3) after the booster. The study is continuing to monitor persistence of antibody responses.
Juan Carlos Jaramillo M.D., Chief Medical Officer of Valneva, commented, "Lyme disease represents a high unmet medical need which impacts the lives of millions of people in the Northern Hemisphere. We are excited by these additional Phase 2 results, which we believe take us a step closer to making a major contribution against this severe disease, subject to regulatory approval."
"The prevalence and geographic reach of Lyme disease is growing, underscoring the major medical need for vaccination against the disease," adds Kathrin Jansen, PhD, Senior Vice President and Head of Pfizer Vaccine Research and Development. "These positive results of the Phase 2 VLA15-202 study represent another important milestone in the development of VLA15, and we look forward to continue our development efforts in our quest to potentially protect people from Lyme disease in the future."
About VLA15
VLA15 is the only active Lyme disease vaccine candidate 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, and covers the six OspA serotypes that are prevalent in North America and Europe. OspA is one of the most dominant surface proteins expressed by the bacteria when present in a tick. 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 20172.
Valneva and Pfizer announced a collaboration for VLA15's development and commercialization at the end of April 2020. The two companies are working closely together on the next development steps and are planning for a Phase 3 trial in 2022.
About Phase 2 Clinical Study VLA15-202
VLA15-202 is a randomized, observer-blind, placebo controlled trial conducted in the US.
A total of 246 healthy volunteers18 to 65 years of age received 135 µg (N=97), or 180 µg (N=98) of VLA15 or placebo (N=51)).
VLA15 was tested as alum adjuvanted formulation and was administered intramuscularly at Month 0-2-6.
Participants were followed for an additional 12 months, with the primary immunogenicity readout at one month after completion of the primary vaccination series (Primary Endpoint). A subset of participants who received a complete primary vaccination series in the 180 µgdose level VLA15 group, were invited to continue the study into a booster phase and were randomized to receive an additional 180 µg dose of VLA15 (N=39) or placebo (N=19) at Month 18.
Study centers are located in areas where Lyme disease is endemic; volunteers with a prior history of Lyme disease, were also enrolled.
About Lyme Disease
Lyme disease is a systemic infection caused by Borrelia burgdorferi bacteria transmitted to humans by infected Ixodes ticks3. It is considered the most common vector- borne illness in the Northern Hemisphere. According to the U.S. Centers for Disease Control and Prevention (CDC), approximately 476,000 Americans are diagnosed and treated for Lyme disease each year4, and there are at least a further 200,000 cases in Europe annually5. 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 widens6.
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.
