P-1070. Safety and Efficacy of Replacement with Contezolid-Containing Regimens in Patients with Multidrug-Resistant/Rifampicin-Resistant Tuberculosis Who are Intolerant to Linezolid-Containing Regimens: a Retrospective Case Analysis

Abstract Background Linezolid, commonly used in the treatment of multidrug-resistant tuberculosis (MDR-TB), has limitations due to adverse effects such as myelosuppression, optic neuropathy. Contezolid, a new oxazolidinone, was developed to reduce toxicity. This preliminary study focused on the potential utility of contezolid in the treatment of MDR-TB. Methods This is a retrospective case analysis, thirteen MDR/rifampicin-resistant(RR) TB patients who were switched to contezolid-containing regimens due to adverse reactions during treatment with linezolid-containing regimens were included. Linezolid was administered 600mg once daily for 6-24 weeks, contezolid was given 400mg twice daily for 4 months to 1 year. The results of drug sensitivity test (DST), regimens containing linezolid or contezolid and treatment duration, occurrence of adverse reactions, timing of treatment adjustment, adverse reactions and efficacy are described. Results The basic information and treatment related results were shown in Table 1. All of 13 patients experienced adverse reactions during the treatment of linezolid-containing regimens, of which 9 (69.2%) were severe. The time to myelosuppression after linezolid initiation was approximately 8 weeks, and 16 weeks for neurotoxicity. After at least 4 weeks of switching to regimens containing contezolid, 95% of patients with linezolid-related adverse reactions were alleviated or improved. At the end of the third month after treatment adjustment, the WBC, PLT and hemoglobin level of 13 patients returned to pre-treatment level, and the lower limb numbness of 2 patients were improved. Sputum mycobacterium tuberculosis culture and sputum smears acid fast stain of 13 patients turned negative or continued negative, and no case of positive recurrence. Follow-up chest computed tomography showed no evidence of disease progression. Conclusion This study showed that contezolid were not only safer than linezolid but also demonstrated clinical improvement in all included patients with MDR-TB. This study supports the hypothesis that contezolid may provide an effective and safe alternative to linezolid in the management of MDR-TB in the future. Disclosures All Authors: No reported disclosures