When physicians diagnose Lyme disease, they usually prescribe standard antibiotics — and for many patients, that's enough. But for 10 to 20 percent of patients, the disease persists, causing joint paint, neurological difficulties and fatigue, among other symptoms.
New drugs, capable of completely eliminating the disease-causing bacteria Borrelia burgdorferi at the onset, are needed. And a new study shows that a team of Stanford researchers has discovered a few promising leads.
In work appearing today in the journal Drug Design, Development and Therapy, researchers led by Jayakumar Rajadas, PhD, tested 4,366 drug compounds for their efficacy against B. Burgdorferi in the dish. They picked the top 20, which have all been approved by the Food and Drug Administration for a variety of uses (one, for example, is used to treat alcohol abuse), and subjected them to additional tests. These compounds blocked the growth of between 95 and 99.8 percent of the bacteria in the samples.
A key caveat: These compounds, if taken successfully through the approval process, could be beneficial for those with new Lyme disease diagnoses. The drugs are not being considered for use for patients who are currently struggling with persistent Lyme symptoms.
"We know the way we treat the patient during the acute period (after infection) is critical. If we treat them with a very effective antibiotic that can kill the bacteria even in the beginning state, we can possibly avoid this 10 to 20 percent of patients who always have the disease," Rajadas said. He directs the Stanford Biomaterials and Advanced Drug Delivery Laboratory (bioADD) and is a member of the Lyme Disease Working Group. The lead author is Venkata Raveendra Pothineni, PhD, a postdoctoral researcher at bioADD.
Other groups worldwide are striving to improve treatments for Lyme disease. Rajadas attributed the team's preliminary success to access at Stanford to the equipment, supplies and know-how to develop a new assay capable of quickly identifying the most successful compounds. The team used a technique called high-throughput screening, which rapidly allows researchers to examine hundreds of compounds.
Tests on the compounds are ongoing, Rajadas said: "We are trying to take it to the clinic."
Laura Roberts, MD, chair of the Department of Psychiatry and Behavioral Sciences and co-chair of the Lyme Disease Working Group, lauded the work:
Dr. Rajadas and members of his laboratory have worked for years to dismantle barriers to understanding Lyme disease. The use of high-throughput screening to assess candidate compounds is a welcome innovation with important results for new drug development. Patients with chronic consequences of Lyme borreliosis infection are waiting for new discoveries that will bring a cure. Dr. Rajadas's scientific efforts bring that day closer.
Another member of the Lyme Disease Working Group, Cheryl Koopman, PhD, professor of psychiatry and behavioral sciences, emeritus, is also pleased with the outcome, telling me, "This study identifies new directions for potential advances in treating Lyme disease and its sequelae."
Previously: Stanford study finds Lyme disease among ticks in California parks, Hikers beware: New tick-borne disease discovered in Northern California parks and Using "nanobullets" for good — not evil
Photo by JerzyGorecki