Oral doxycycline versus intravenous ceftriaxone for treatment of multiple erythema migrans: an open-label alternate-treatment observational trial

Background: Several guidelines advocate the same treatment approaches for both early disseminated Lyme borreliosis, manifested as multiple erythema migrans (EM), and early localized Lyme borreliosis, manifested as solitary EM. Methods: Oral doxycycline (100 mg q12h) was compared on a non-inferiority premise with intravenous ceftriaxone (2 g q24h) for 14 days in 200 adult European patients with multiple EM in an open-label alternate-treatment observational trial performed in a single-centre university hospital. Treatment outcome was assessed at 14 days and at 2, 6 and 12 months post-enrolment. Non-specific symptoms in patients and 192 control subjects without a history of Lyme borreliosis were evaluated and compared. This trial was registered at http://clinicaltrials.gov (identifier NCT01163994). Results: At the 12 month visit, 4/82 (4.9%) multiple EM patients prescribed doxycycline and 6/88 (6.8%) multiple EM patients prescribed ceftriaxone showed incomplete response manifested predominantly as post-Lyme symptoms (1.9% difference, upper limit of 95% CI 5.1%). The upper limit of 95% CI for the difference in proportion of patients with incomplete response between doxycycline and ceftriaxone groups did not exceed the predetermined non-inferiority margin of 10%. The frequency of non-specific symptoms in patients was similar to that in controls. Conclusions: The 14 day oral doxycycline was not inferior to the 14 day intravenous ceftriaxone in treatment of adult European patients with early disseminated Lyme borreliosis manifested as multiple EM. The frequency of non-specific symptoms in patients was similar to that in controls without a history of Lyme borreliosis.