摘要Background::Toxoplasmic encephalitis (TE) is the most frequent cause of expansive brain lesions among patients with acquired immunodeficiency syndrome (AIDS). However, the optimal timing of antiretroviral therapy (ART) initiation in these patients remains controversial. This study aims to investigate the differences in outcomes of ART initiation at different times, in order to help clarify the treatment timing of AIDS-associated TE.Methods::This multicenter prospective observational study included 87 patients recruited from 11 research centers in China (from March 2019 to December 2022). Of the patients, 38 were assigned to the early ART group (initiating ART within 2 weeks after anti- Toxoplasma treatment initiation), and the remaining 49 patients received deferred ART (initiating ART at least 2 weeks after anti- Toxoplasma treatment initiation). The main outcomes included mortality and emergence of immune reconstitution inflammatory syndrome (IRIS). Human immunodeficiency virus (HIV)-1 viral load and CD4 + T-cell counts at weeks 24 and 48 were observed. Results::The number of deaths (1 vs. 5, P = 0.225) and incidence of IRIS (2.6% vs. 0, P = 0.437) were not significantly different between the early and deferred ART groups at week 48. Early ART initiation did not contribute significantly to HIV-1 viral load control (<50 copies/mL, n = 8 vs. n = 3 at week 24, P = 0.142; n = 7 vs. n = 7 at week 48, P = 1.000). The median CD4 + T-cell counts between the two groups were not significantly different, either at week 24 (155 vs. 91 cells/mm 3, P = 0.837) or at week 48 (181 vs. 146 cells/mm 3, P = 0.219). Conclusion::In patients with AIDS-associated TE, early ART initiation was not significantly different from deferred ART initiation in terms of incidence of mortality, IRIS, and HIV virological and immunological outcomes.Trial registration::This study was registered (registration number: ChiCTR1900021195) as one of 12 clinical trials under the title of a general project at the Chinese Clinical Trial Registry (chictr.gov) on February 1, 2019. Enrollment for this study began in March 2019.