​Antibiotic shows promise against Lyme disease at a fraction of the dosage

Lyme disease affects nearly half a million individuals in the United States annually. The disease caused by the bacterium Borrelia burgdorferi and rarely, Borrelia mayonii is spread to humans through the bite of infected blacklegged ticks, known as deer ticks. Lyme disease can be devastating even in acute cases, so early treatment with antibiotics is crucial to prevent chronic symptoms like heart and neurological problems and arthritis.

Scientists from Northwestern University have found that a specific antibiotic can cure Lyme disease effectively, and only requires 1/100th of the dose of the treatment currently being used. The study published in the journal Science Translational Medicine revealed that piperacillin, an antibiotic in the same class as penicillin, effectively Lyme disease in mice at 100 times less than the dose of doxycycline, the current gold standard treatment. The study revealed that at such a low dose, piperacillin also had the added benefit of “having virtually no impact on resident gut microbes.”

Though doxycycline and other generic antibiotics treat the disease, they wreak havoc on the microbiome by killing the beneficial gut bacteria. Doxycycline also fails in 10 and 20% of individuals who take it, and it is not approved for use in young children, who are especially at the highest risk of tick bites, resulting in Lyme.

“Powerful, broad-spectrum antibiotics that kill extracellular bacteria are seen as the most effective medication because physicians want to just kill the bacterium and don't care how. This is certainly a reasonable approach, but I think the future for Lyme disease patients is bright in that we are approaching an era of customized medicine, and we can potentially create a particular drug, or a combination to treat Lyme disease when others fail. The more we understand about the various strains and species of Lyme disease-causing Borrelia, the closer we get to a custom approach,” Brandon L. Jutras, who led the research, and ios an associate professor in the microbiology-immunology department of Northwestern University Feinberg School of Medicine, and a member of Northwestern’s Center for Human Immunobiology, said in a statement.

The researchers stated that the piperacillin, which has already been FDA-approved as a safe treatment for pneumonia, could also be used as a preventive treatment. If someone is bitten by a deer tick and might have been exposed to Lyme disease, they could get a one-time shot of the medication to help prevent infection.

The study said that penicillin is relatively the most effective and targeted treatment. Piperacillin is usually given with another drug, tazobactam, to treat serious strep infections. This is because strep can block piperacillin from working unless tazobactam is there to stop the enzyme that breaks it down. Jutras also looked at the option of using both drugs together as they might work better than using piperacillin alone.

“Bacteria are clever. Strep and some other bacteria combat antibiotics by secreting beta-lactamases that inactivate piperacillin. We found the approach is totally irrelevant in the context of Lyme disease, and another way that makes piperacillin more specific. Adding the beta-lactamase inhibitor doesn’t improve the therapy because Lyme Borrelia don’t produce beta-lactamase, but the cocktail does negatively impact the microbiome by becoming more broadly functional against beneficial residents,” Jutras added.

Curbing Lyme disease is a challenge, given that there are no approved human vaccines as of now, and this new research could be a way forward.