RT Journal Article T1 Repurposing insights: experimental and pharmacological approach on L-captopril and dimercaprol as metallo-β-lactamase inhibitors A1 Rodríguez-Avial Infante, Iciar A1 Torres, Sthefany A1 Puglla, Yuri A1 Pérez Martín, Laura A1 Sebastianes, Juan Luis A1 Delgado-Iribarren García-Campero, Albert A1 Culebras López, Esther A1 Valderrama Conde, María José AB The design of specific inhibitors of metallo-β-lactamases (MBL) is one of the priority research lines due to the spread of carbapenem resistant bacterial strains which limits therapeutic options. In parallel, the investigation of new uses of known medicines is prompted by regulatory agencies. In this work, the potential MBL inhibitory potency of L-captopril (an antihypertensive drug) and dimercaprol (used in poisoning by metals) was investigated in a clinical collection of Enterobacterales and Pseudomonas spp. In addition, a comprehensive review of the available literature was conducted, to discuss jointly new and previously available data. The results indicate that activity of imipenem and meropenem combined with 400 mg/l is restored for > 80% and 60%, respectively, for Enterobacterales strains, but not in the Pseudomonas group. Dimercaprol had a limited activity in both bacterial groups. Based on these promising results of L-captopril, pharmacological calculations were performed. It is concluded that the repurposing objective could not be achieved as the overall data indicated that the concentrations of captopril required to achieve carbapenemase inhibitory activity in vivo are higher than maximum used in treatment. Communication of negative results would help to discontinue active current research on L-captopril and should focus on other potential MBL inhibitors. PB Oxford University Press SN 0378-1097 YR 2026 FD 2026-05 LK https://hdl.handle.net/20.500.14352/138847 UL https://hdl.handle.net/20.500.14352/138847 LA eng NO Icíar Rodríguez-Avial, Sthefany Torres, Yuri Puglla, Laura Pérez-Martín, Juan-Luis Sebastianes, Alberto Delgado-Iribarren, Esther Culebras, María-José Valderrama, Repurposing insights: experimental and pharmacological approach on L-captopril and dimercaprol as metallo-β-lactamase inhibitors, FEMS Microbiology Letters, Volume 373, 2026, fnag064, https://doi.org/10.1093/femsle/fnag064 NO The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Open Access funding provided, thanks to the CRUE-CSIC agreement with Springer Nature. DS Docta Complutense RD 20 ago 2026