A total of 129 volunteers enrolled in the two studies. All participants had well-documented Lyme disease and had previously received at least one course of recommended antibiotics. Despite prior antibiotic treatment, the volunteers currently suffered from persisting muscle or joint pains and complained of memory and thinking problems, often associated with fatigue.
Although both trials were identical in design, one trial enrolled 78 chronic Lyme disease patients who tested positive for antibodies to the Lyme bacterium, while the other trial enrolled 51 people with chronic symptoms but no evidence of antibodies.
In each study, volunteers were assigned at random to receive either antibiotic treatment or an inactive placebo. Treatment consisted of intravenous ceftriaxone, 2 grams daily, for 30 days, followed by oral doxycycline, 200 milligrams daily, for 60 days. The investigators evaluated symptom improvement based on the patients responses to a health-related quality-of-life questionnaire given 90 days after they completed the course of antibiotic treatment or placebo.
An interim data analysis planned into the design of the trials was carried out last November by a Data and Safety Monitoring Board (DSMB), an independent group of doctors and researchers. The DSMB unanimously recommended that NIAID stop the treatment arm of both trials because the data showed no significant difference in the percentage of patients who received either antibiotic treatment or placebo who felt their symptoms had improved, worsened, or stayed the sa
Contact: Laurie K. Doepel
NIH/National Institute of Allergy and Infectious Diseases