Efficacy and Safety of Contezolid as an Alternative to Linezolid for Treating MRSA Spinal Infections Following Linezolid-Induced Thrombocytopenia: A Single-Center Retrospective Study

Xiucui Zhang,* Jianrong Wang,* Xinghao Cao, Shijie Wang, Junxue Wang, Huili Huang, Bo Wei Department of Infectious Diseases, Second Affiliated Hospital of Naval Medical University, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Bo Wei, Department of infectious Disease, Second Affiliated Hospital of Naval Medical University, Shanghai, People’s Republic of China, Tel +15921231996, Email [email protected] Huili Huang, Department of Infectious Disease, Second Affiliated Hospital of Naval Medical University, Shanghai, People’s Republic of China, Email [email protected]: Methicillin-resistant Staphylococcus aureus (MRSA)-associated spinal infections (SI) typically require prolonged antibiotic therapy. While linezolid (LZD) demonstrates efficacy against MRSA-SI, its clinical utility is often limited by the risk of thrombocytopenia. Contezolid (CZD), a novel oral oxazolidinone, potentially presents a lower risk of myelosuppression; however, clinical evidence supporting its use in SI remains limited. This retrospective study evaluated patients with MRSA-SI who transitioned to CZD (800 mg orally twice daily) after developing LZD-induced thrombocytopenia. Clinical outcomes, adverse events, and platelet recovery were assessed. All cases were identified from the Department of Infectious Diseases at the Second Affiliated Hospital of Naval Medical University. The study period was between November 2022 and April 2024, with a follow-up period of 8 to 24 weeks. Eight patients were included (median age 61 years; range 40– 78). The median LZD treatment duration was 12 days (range 7– 14), resulting in a decline in platelet counts from 125– 300 × 109/L to 65– 89 × 109/L. Following transition to CZD (mean duration 66.6 ± 51.2 days; range 28– 168), all patients achieved clinical success with no further platelet reduction. Platelet recovery to baseline or normal levels occurred within a mean of 8.25 ± 3.4 days (range 4– 14). Three patients experienced gastrointestinal adverse events (nausea and vomiting), predominantly after the first dose. Our findings suggest that CZD may represent an effective and safe salvage therapy for patients with MRSA-SI who develop LZD-induced thrombocytopenia. Larger prospective studies are warranted to validate these preliminary findings.Keywords: spinal infections, linezolid, thrombocytopenia, contezolid, MRSA