Lyme disease, caused by the spirochete Borrelia burgdorferi, is the most common tick-borne illness in the United States. Typically, after being bitten by an infected tick, patients will notice an expanding rash and flu-like symptoms. Most patients recover fully after initial treatment with antibiotics such as doxycycline or amoxicillin. Some patients, however, do not recover fully or their symptoms return within a few months after having completed antibiotic treatment. Common persistent symptoms include fatigue, joint pain, muscle pain, numbness, tingling, burning pains, and changes in mood, memory or mental clarity. These symptoms can last months to years after treatment and, when accompanied by functional impairment, are collectively referred to by the academic community as "Post Treatment Lyme Disease Syndrome (PTLDS)". Patients however typically refer to this constellation of persistent symptoms as "Chronic Lyme Disease".
There are several possible explanations for why patients may have persistent symptoms, including persistent infection and post-infectious changes triggered by the prior infection.
Scientists recently discovered that disulfiram is effective in the lab setting at killing the microbes that cause Lyme disease. Disulfiram is more commonly known as "Antabuse". It is an FDA-approved compound used to assist alcoholics in resisting alcohol consumption. Most remarkable is that disulfiram was effective at killing not only the actively replicating Lyme bacteria (ie, the ones that are typically killed by several antibiotics) but also the relatively dormant or quiescent Lyme bacteria (these are called "drug-tolerant persisters") - these latter spirochetes are the ones that may account for the development of chronic Lyme disease symptoms.
This initial pilot study will focus on patients with persistent symptoms despite having received the standard antibiotic therapy (or more) for Lyme disease. Because no one has yet studied the safety of disulfiram for patients with a history of Lyme disease and because the investigators do not know the optimal treatment duration for disulfiram, the initial effort will have the primary aims of assessing safety and determining whether a longer course of daily treatment is more effective than a shorter course of daily treatment.
The investigators propose therefore a small 14-week randomized placebo-controlled pilot study enrolling 24 patients with persistent symptoms despite prior antibiotic treatment for Lyme disease (known as Post-treatment Lyme Disease Syndrome). Among the 24 disulfiram-treated patients, half will get 8 weeks of disulfiram and the other half will get a shorter duration of disulfiram for 4 weeks followed by 4 weeks of matching placebo. After week 8, patients will be off pills for 2 weeks for the primary week 10 evaluation and then for another 4 weeks for the week 14 follow-up evaluation. This will be a double-blinded study; neither physician nor patient will know which treatment group the patient is assigned to.
With this initial study, the investigators will be able to evaluate the side effects, tolerability and initial signs of the effectiveness of disulfiram in reducing symptoms among the 24 patients assessed. The results of this study will guide the investigators regarding whether a larger definitive randomized trial should be conducted and which treatment schedule is optimal.
