Comparative Outcomes of Meropenem and Imipenem in Multidrug-Resistant Pulmonary Infections: A Prospective Cohort Study.

Pulmonary infections due to multidrug-resistant (MDR) organisms (MDRO) pose a significant global public health challenge due to their high mortality rates and complex management. Carbapenem antibiotics, including Meropenem and Imipenem, are cornerstone therapies for MDR Gram-negative bacterial infections, with their efficacy and safety critically influencing patient outcomes. In this prospective cohort study, we compared the day-7 pathogen clearance rates of Meropenem and Imipenem in MDR bacterial pulmonary infections and also evaluated prespecified secondary clinical and safety outcomes. For the primary endpoint, no statistically significant difference was observed between the two groups in day-7 pathogen clearance (P>0.05). However, supportive secondary analyses showed that the meropenem group had shorter observed times to resolution of cough, sputum production, lung rales, and fever (P<0.05). In addition, meropenem-treated patients showed greater improvement in selected lung function parameters, a more pronounced reduction in PaCO2 (P<0.05), lower post-treatment PCT and hs-CRP levels (P<0.05), and fewer reported adverse events (P<0.05). These observational findings suggest that Meropenem may offer clinical advantages in MDRO-induced pulmonary infections, although the results should be interpreted in the context of the non-randomized study design.