ABSTRACT
BACKGROUND: The optimal duration of treatment for patients with late Lyme disease is unresolved. METHODS: In a prospective, open label, randomized, multi-center study, a 14 day course of ceftriaxone was compared to 28 days of therapy. Entry criteria included objective abnormalities compatible with late Lyme disease and serologic reactivity to Borrelia burgdorferi. Randomization took place prior to obtaining serologic results. Clinical response was rated as cure; improvement; failure; or not assessable. RESULTS: Of the 201 patients randomized, 21 patients in the 14 day group and 37 in the 28-day group were excluded from the study for failure to meet serologic criteria. Of those who met serologic criteria, 80 patients received 14 days and 63 received 28 days of ceftriaxone. At time of last evaluation, there were 5 treatment failures in the 14 day group and none in the 28 day group (p = 0.07). Clinical cure rates were 76% for the 14 day group and 70% for the 28 day group (p = NS). Therapy was discontinued due to adverse events for a significantly greater proportion of patients in the 28-day group compared to the 14-day group (p < 0.02). CONCLUSIONS: Ceftriaxone for 14 days eradicated the signs and symptoms of late Lyme disease in the majority of evaluable patients. Although there were more failures in the 14-day group than in the 28-day group, this study did not have the power to determine if a clinical subset of patients may benefit from 28 days of therapy.