{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T01:08:13Z","timestamp":1788743293847,"version":"build-2803163510"},"reference-count":17,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T00:00:00Z","timestamp":1788739200000},"content-version":"vor","delay-in-days":6,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background and objectives<\/jats:title>\n                    <jats:p>Ertapenem is well suited for outpatient parenteral antimicrobial therapy (OPAT) due to its once-daily dosing and favourable safety profile; however, increasing enzyme-mediated resistance limits its clinical utility. Ertapenem\/zidebactam (WCK 6777) is a novel \u03b2-lactam\/\u03b2-lactam enhancer combination in which zidebactam exhibits high-affinity binding to penicillin-binding protein 2 (PBP2), augmenting ertapenem activity and overcoming \u03b2-lactamase-mediated resistance. We evaluated the in vitro activity of ertapenem\/zidebactam against carbapenem-resistant Escherichia coli and Klebsiella pneumoniae clinical isolates from India.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>MICs of ertapenem\/zidebactam and comparator agents (carbapenems, imipenem\/relebactam, ceftazidime\/avibactam and aztreonam\/avibactam) were determined by broth microdilution method. Carbapenemase genes and PBP3 insertions were identified using PCR.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Ertapenem\/zidebactam demonstrated potent activity against E. coli, inhibiting 99.5% of isolates at the PK\/PD breakpoint of \u22648\u2005mg\/L (MIC90, 0.5\u2005mg\/L), including NDM producers with PBP3 insertions. Against K. pneumoniae, susceptibility reached 93.6% among NDM producers and 88.5% among dual carbapenemase producers at the same breakpoint. Comparator agents showed variable activity, with limited efficacy against metallo-\u03b2-lactamase producers.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The enhanced activity of ertapenem\/zidebactam is attributed to zidebactam\u2019s dual mechanism, \u03b2-lactamase inhibition and high-affinity PBP2 binding, enabling effective coverage despite complex resistance mechanisms. Its once-daily dosing supports its potential as an OPAT-enabling therapeutic option and warrant further clinical development.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jacamr\/dlag167","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T11:18:14Z","timestamp":1788520694000},"source":"Crossref","is-referenced-by-count":0,"title":["<i>In vitro<\/i>\n                    potency of novel ertapenem\/zidebactam combination (WCK 6777) against carbapenemase-producing Enterobacterales collected across India"],"prefix":"10.1093","volume":"8","author":[{"given":"Yamuna Devi","family":"Bakthavatchalam","sequence":"first","affiliation":[{"name":"Department of Clinical Microbiology, Christian Medical College , Vellore ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3299-894X","authenticated-orcid":false,"given":"Robert","family":"Bonomo","sequence":"additional","affiliation":[{"name":"Department of Medicine, Case Western Reserve University School of Medicine , Cleveland, OH ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3564-8603","authenticated-orcid":false,"given":"Adrian","family":"Egli","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology, University of Zurich , Zurich ,","place":["Switzerland"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosmi","family":"Puthan","sequence":"additional","affiliation":[{"name":"Department of Medicine, Case Western Reserve University School of Medicine , Cleveland, OH ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abirami","family":"Shankar","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Christian Medical College , Vellore ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Soniya","family":"Krishnamoorthy","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Christian Medical College , Vellore ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vasant","family":"Nagvekar","sequence":"additional","affiliation":[{"name":"Department of Infectious Disease, Lilavati Hospital & Research Centre , Mumbai ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rajni Sabharwal","family":"Ekadashi","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Mahatma Gandhi Medical College & Hospital , Puducherry ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sudharsana","family":"J","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Baby Memorial Hospital , Kozhikode ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sneha","family":"Rajan","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Narayani Hospital and Research Centre , Vellore ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Camilla","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Department of Microbiology, P. 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Hinduja Hospital and Medical Research Centre , Mumbai ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rangineni","family":"Jayaprada","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Sri Venkateswara Institute of Medical Sciences , Tirupati ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abi","family":"Manesh","sequence":"additional","affiliation":[{"name":"Department of Infectious Disease, Christian Medical College , Vellore ,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Balaji","family":"Veeraraghavan","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Christian Medical College , Vellore 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