Clnical outcomes and safety of contezolid versus linezolid in treatment of elderly patients with severe hospital-acquired pneumonia

Background It has been shown that the efficacy of contezolid, a novel drug against Gram-positive bacteria, is not inferior to that of linezolid and the incidence of side effects is lower than that of linezolid, but its use in the field of hospital-acquired pneumonia (HAP) is still scarce.

Objective To compare the efficacy and side effects of contezolid with those of linezolid in treatment of severe hospital-acquired pneumonia (SHAP) patients.

Methods General and clinical data of patients with SHAP, aged more than 70 years, who developed SHAP from January 1, 2021 to February 15, 2023 and were treated in-hospital with either contezolid (800 mg once/12 h orally) or linezolid (600 mg once/12 h IV or orally) at the Second Medical Center of Chinese PLA General Hospital were retrospectively analyzed. General information, clinical efficacy and side effects of patients in the contezolid and linezolid groups were compared.

Results A total of 358 patients were included, including 111 cases in the contezolid group and 247 cases in the linezolid group. The clinical effectiveness rates of the contezolid group and linezolid group were 55.0% (61/111) and 61.1% (151/247), respectively. The proportion of platelet decrease was 54.1% (60/111) in the contezolid group and 78.9% (195/247) in the linezolid group, the proportions of hemoglobin decrease were 56.8% (63/111) and 64.4% (159/247), respectively, and 61.3% (68/111) and 63.2% (156/247) for erythrocyte decline, respectively. After performing tilt-score matching, a total of 36 patients each were matched with contezolid and linezolid, and the differences in clinical efficiency (61.1% vs 69.4%, P=0.458) and microbial clearance (22.2% vs 27.8%, P=0.296) between the two groups were not statistically significant. The incidence of platelet decline in the contezolid group was significantly lower than that of linezolid (50% vs 80.6%, P=0.006). However, the incidence of haemoglobin decline in the contezolid and linezolid groups was 41.7% and 61.1%, the incidence of erythrocyte decline was 50% and 61.1%, the incidence of lactic acid elevation was 44.1% and 54.3%, and the incidence of lactic acidosis was 29.4% and 34.3%, respectively, and the differences between the two groups were not statistically significant (P＞0.05).

Conclusion The efficacy of contezolid in the treatment of elderly patients with SHAP is comparable to that of linezolid, but the incidence of platelet drop caused by it is significantly lower than that of linezolid.