Pfizer and Valneva have released promising results from the Phase 2 clinical trial of their new Lyme disease vaccine, VLA15. While an antibody response remained in all groups after month 18, levels had declined, suggesting that a booster jab is required. The latest development brings the VLA15 vaccine one step closer to patients.
The VLA15 works by targeting the outer surface protein A (OspA) of the bacteria that causes Lyme disease (Borrelia burgdorferi). While Lyme disease can be treated effectively with antibiotics if diagnosed early enough, an effective vaccine could provide cost-effective protection for those at high risk of Lyme disease infection.
During the 18-month VLA15 Phase 2 clinical trial, the new vaccine was tested on 246 adults aged 18-65 in the US. All groups received a vaccine in months 0, 2 and 6. In October 2020, scientists announced their initial findings that VLA15 was immunogenic across all dose groups tested and elicited high antibody responses across all serotypes (ST1 – ST6) after one month. In addition, no serious adverse events (SAEs) were observed, strongly suggesting that the vaccine is safe.
The latest results, released in late September 2021, confirm that an antibody response remains after 18 months, but it declines – strongly suggesting a booster shot is required.
Participants in the trial were invited to continue in the trial and offered a booster shot. The booster shot proved to be highly effective, demonstrating “a strong anamnestic response” in all those who received it. Tests showed response levels were three-four times higher than those measured during the initial course of treatment.
“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 continuing our development efforts in our quest to potentially protect people from Lyme disease in the future.”
Pfizer and Valneva are planning for a Phase 3 clinical trial to begin in 2022. Phase 3 clinical trials involve a much larger group of patients and will provide crucial information on the safety and efficacy of the treatment.
The VLA15 vaccine was granted Fast Track designation by the US Food and Drug Administration (FDA) in July 2017, accelerating its development. Still, even so, it will be several years before the vaccine is commercially available. Until then, patients with suspected Lyme disease must receive a confirmed diagnosis as soon as possible.
Biocentaur’s PrimeSpot test can quickly and accurately identify the presence of Lyme disease-associated species in a DNA sample, providing a rapid diagnosis. Used in combination with our PaldiSpot test, clinicians can diagnose Lyme disease and identify its specific strain. Rapid detection and diagnosis are essential to starting treatment and improving outcomes.
You can read the official announcement on Phase 2 clinical trial results from Pfizer and Valneva here.