For Treating Early Syphilis, Oral Linezolid Failed

Alternative treatments for syphilis, preferably with orally administered medications, are urgently needed. Linezolid has bactericidal properties in vitro against Treponema pallidum. Investigators in Catalonia randomized persons with early syphilis (primary, secondary, or early latent) to receive oral linezolid (600 mg once daily for 5 days) or intramuscular benzathine penicillin G (2.4 mIU; standard of care). Treatment response was defined as clinical improvement, a fourfold decline in rapid plasma reagin titer, and absence of relapse.

The trial was stopped early for futility after 59 participants (all men) had been randomized. In the penicillin arm, 100% of 28 participants responded as compared with 19 of 27 (70%) in the linezolid arm. Alth…