Trimethoprim-sulfamethoxazole versus placebo to reduce the risk of recurrences of toxoplasma gondii retinochoroiditis: randomized controlled clinical trial – Accepted Manuscript

Abstract: Purpose: To compare the effects of trimethoprim-sulfamethoxazole versus placebo in reducing the risk of recurrences of toxoplasma gondii retinochoroiditis.Design: Single-center, prospective randomized, double-masked, clinical trial.Methods: A total of 95 patients from Campinas, Brazil, with active recurrent toxoplasma gondii retinochoroiditis were included. The initially active toxoplasmosis lesions were successfully treated in all cases using trimethoprim-sulfamethoxazole (800 mg/160 mg) twice daily for 45 days. Subsequently, five patients dropped out of the study. The remaining patients were randomized to group 1 (trimethoprim/sulfamethoxazole tablet every two days) or group 2 (identical placebo tablet every two days). Randomization was 1:1, was stratified by gender and used blocks sizes of four. The primary outcome was recurrent toxoplasmosis retinochoroiditis within one year, and the secondary outcome was a 1-year change in best correct visual acuity/BCVA (ETDRS chart).Results: The incidence of recurrent toxoplasmosis retinochoroiditis within 12 months was 0/46 (0%) and 6/47 (12.80%) in the trimethoprim-sulfamethoxazole and placebo groups, respectively (P = .026). Visual acuity improvements in the two groups were similar. No treatment-limiting toxicity was observed.Conclusions: Trimethoprim/sulfamethoxazole therapy resulted in a 100% reduction in the recurrence of toxoplasma gondii retinochoroiditis over one year of treatment.