Lyme disease has become an insidious epidemic in the United States. Caused by bacteria transmitted through the bite of an infected tick, it can lead to heart problems, meningitis or arthritis if left untreated. It is the most common tick-borne illness in the United States, and the Centers for Disease Control and Prevention estimates that around 475,000 people likely contract the disease each year.
Scientists, doctors and ecologists have worked for decades to slow the spread of Lyme and the blacklegged, or deer, ticks that carry the disease-causing bacteria. However, the ticks’ range continues to expand. Today, over 50% of the American population lives in an area where these ticks are found.
The U.S. Food and Drug Administration approved a vaccine against Lyme in 1998, but it was met by controversy and was pulled from the market three years later. Efforts continue today to create a human vaccine as well as to stop the spread of Lyme by other means, including using gene editing to immunize mice that can transmit the bacteria to ticks, killing deer and using pesticides to control ticks.
My colleagues and I have been working on a different kind of prevention: a yearly injection. I am an infectious diseases physician-scientist and have been studying and working toward preventing Lyme disease for much of my career. Our recent work on preventing Lyme disease has been conducted at University of Massachusetts Medical School’s MassBiologics, the only nonprofit, FDA-licensed manufacturer of vaccines and biologics in the United States.
Our method, known as Lyme PrEP, delivers a single anti-Lyme antibody directly to a person rather than triggering the patient’s own immune system to make many antibodies, as vaccines do. It is designed to be a seasonal shot that people can get once a year before tick season begins in April. We have published several peer-reviewed articles on this method, including on its success in mice and nonhuman primates.
In February 2021, we received approval from the FDA to proceed with the first human clinical trial of Lyme PrEP, and all of the volunteers in this trial have been enrolled and received the shot. Our goal for this study, also known as the phase 1 clinical trial, is to test the safety of the new medicine and determine how long it might stay in the bloodstream and prevent Lyme disease.
The preliminary results from the trial are very encouraging: They show that Lyme PrEP is safe and should be effective during the entire nine-month season when most people acquire Lyme disease.