Lyme disease is a brutal illness and anyone that suffers from it wouldn’t wish it on their worst enemy. Many patients have to go through multiple Doctors and years of medical run-around to finally be correctly diagnosed with Lyme Disease. Could a vaccine help spare others the same fate?
A research paper published in The Lancet Infectious Diseases reported promising phase 1/2 clinical trial results on an investigational Lyme Disease vaccine. The study, run by scientists from Stony Brook University, Brookhaven National Laboratory, and Baxter International Inc. analyzed the safety and immune response potential of the vaccine. The 300 volunteers received three primary immunizations and then one booster. All types and doses of the vaccine, some of which had an adjuvent (an additive that triggers an immune response to the vaccine) resulted in significant antibodies against all species of Borrelia.
“The results of a clinical trial conducted by Baxter are promising because the vaccine generated a potent human immune reaction, covered the complete range of Borrelia active in the entire Northern hemisphere, and produced no major side effects (researchers reported only mild adverse reactions were seen).” Dr. Luft
This all sounds really exciting… and it could be. But this is not the first attempt at a Lyme Disease vaccine, which makes some patients who have seen researchers go down this road before, very wary.
The first and only licensed Lyme Disease vaccine approved by the FDA was called LYMErix and was developed by SmithKline Beecham (now GlaxoSmithKline). It was given in a three dose series and had a unique way of acting: it stimulated antibodies that attacked the Lyme bacteria in the tick’s gut as it fed on the human host, before the bacteria were ever able to enter the body.
Vaccinated individuals showed a 76% reduction in Lyme disease in the year following vaccination, with no significant side-effects noted. Based on these promising findings, the U.S. Food and Drug Administration (FDA) approved LYMErix™ on 21 December 1998. Source
The vaccine was not without issues even as it hit the market. First: after you received the initial injection you needed it again 1 month and 12 months later, while possibly needing booster shots every year since it was unknown how long immunity might last. Secondly with less than 80% efficacy it still left 20% of people unprotected and an unknown number of people that wouldn’t be as careful in tick infested areas if they thought the vaccine was magically protecting them completely, but weren’t receiving the boosters.
What happened next depends on who you ask (like most things in the medical world). Reports began to surface of people developing an autoimmune arthritis, of having it trigger their then dormant Lyme disease, and maybe worst of all – some people reported they actually contracted Lyme disease from the vaccine itself.
A lawsuit was filed in Dec. 1999 claiming 30 percent of the population has a predisposition to a degenerative autoimmune syndrome which can be triggered by contents of the vaccine. They stated SmithKline Beecham used high concentrations of OspA (outer surface protein A of Borrelia burgdorferi) as the foundation for the vaccine. The amount of OspA entering the bloodstream at any point in the three dose LYMErix vaccine placed patients who are HLA-DR4+ at risk of developing “treatment resistant Lyme arthritis”.
By 2001, with over 1·4 million Lyme vaccine doses distributed in the United States the vaccine side effects database included 905 reports of mild self-limited reactions and 59 reports of arthritis associated with vaccination. Many believe the reporting process broke down and many reactions were never reported. The FDA investigated and found no suggestion that the Lyme vaccine caused harm to its recipients, in part because they believed the arthritis incidence in the patients receiving LYMErix occurred at the same rate as the background in un-vaccinated individuals. Many patients that feel they were severely harmed by the vaccine, disagree. In 2002, with mounting pressure from Doctors and the community, SmithKline Beecham withdrew LYMErix from the market citing financial issues.
What now?
Dr. Luft said one of the main challenges of developing a Lyme disease vaccine is for it to be effective, it will need to work on more than one protein like the previous vaccine. A vaccine needs to be designed to protect against a variety of Borrelia species that spread Lyme disease worldwide. He believes this new vaccine could do just that.
Drs. Luft and Dunn focused vaccine development on the most abundant Borrelia outer surface protein found when the spirochete bacteria reside in ticks. Using the scaffold of this protein, called OspA, they, in collaboration with researchers at Baxter, bioengineered a set of unique OspA proteins not found in nature.” These new OspAs share different parts from different species of Borelia.
“After a series of experiments and refinements, formulations consisting of these new OspA proteins were shown to protect against a broad spectrum of Lyme disease spirochetes. We hope that a larger-scale, Phase 3 trial will demonstrate not only a strong immune response but true efficacy in a large population that illustrates protection against Lyme disease” said Dr. Luft.
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