{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T13:55:17Z","timestamp":1790690117702,"version":"4.1.0"},"reference-count":41,"publisher":"American Society for Microbiology","license":[{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"funder":[{"DOI":"10.13039\/501100020950","name":"National Science and Technology Council","doi-asserted-by":"publisher","award":["112-2320-B-039-053"],"award-info":[{"award-number":["112-2320-B-039-053"]}],"id":[{"id":"10.13039\/501100020950","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004391","name":"China Medical University Hospital","doi-asserted-by":"publisher","award":["C1140729026"],"award-info":[{"award-number":["C1140729026"]}],"id":[{"id":"10.13039\/501100004391","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004391","name":"China Medical University Hospital","doi-asserted-by":"publisher","award":["DMR-114-149"],"award-info":[{"award-number":["DMR-114-149"]}],"id":[{"id":"10.13039\/501100004391","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Microbiol Spectr"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      Carbapenem-resistant\n                      <jats:italic toggle=\"yes\">Acinetobacter baumannii<\/jats:italic>\n                      (CRAB) poses a major therapeutic challenge due to the limited availability of effective treatment options and is associated with substantially increased mortality in healthcare-associated infections. Zosurabalpin (ZAB, RG6006) is a novel macrocyclic peptide (MCP) antibiotic that exerts its antibacterial activity by inhibiting lipopolysaccharide transport, ultimately leading to bacterial cell death. This study evaluated the\n                      <jats:italic toggle=\"yes\">in vitro<\/jats:italic>\n                      activities of ZAB and other antimicrobial agents against clinical CRAB isolates. A total of 206 clinical\n                      <jats:italic toggle=\"yes\">A. baumannii<\/jats:italic>\n                      isolates were collected, including 189 CRAB and 17 carbapenem-susceptible\n                      <jats:italic toggle=\"yes\">A. baumannii<\/jats:italic>\n                      (CSAB). Minimum inhibitory concentrations (MICs) of ZAB were determined using broth microdilution in cation-adjusted Mueller\u2013Hinton broth supplemented with 20% heat-inactivated horse serum. MICs of 11 other comparator agents, including cefiderocol (FDC) and colistin (COL), were determined following Clinical and Laboratory Standards Institute (CLSI) guidelines.\n                      <jats:italic toggle=\"yes\">A. baumannii<\/jats:italic>\n                      NCTC 13304 was used as the quality control strain for zosurabalpin. MIC values for\n                      <jats:italic toggle=\"yes\">A. baumannii<\/jats:italic>\n                      NCTC 13304 tested with ZAB ranged from 0.03 to 0.06 \u00b5g\/mL (reference range: 0.016\u20130.12 \u00b5g\/mL). ZAB demonstrated potent\n                      <jats:italic toggle=\"yes\">in vitro<\/jats:italic>\n                      activity against CRAB, with MIC\n                      <jats:sub>50<\/jats:sub>\n                      and MIC\n                      <jats:sub>90<\/jats:sub>\n                      values of 0.25 and 1 \u03bcg\/mL, respectively. Among FDC-resistant CRAB isolates, the MIC\n                      <jats:sub>50<\/jats:sub>\n                      \/MIC\n                      <jats:sub>90<\/jats:sub>\n                      remained 0.25\/1 \u03bcg\/mL, and for COL-resistant CRAB isolates, the MIC\n                      <jats:sub>50<\/jats:sub>\n                      \/MIC\n                      <jats:sub>90<\/jats:sub>\n                      was 0.5\/2 \u03bcg\/mL. Notably, a CRAB isolate, which was resistant to both FDC and COL, exhibited a ZAB MIC of 0.5 \u03bcg\/mL. This study demonstrated that ZAB exhibited potent\n                      <jats:italic toggle=\"yes\">in vitro<\/jats:italic>\n                      activity against CRAB, independent of resistance to FDC and\/or COL. These findings support ZAB as a promising therapeutic candidate for difficult-to-treat CRAB infections.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>IMPORTANCE<\/jats:title>\n                    <jats:p>\n                      Carbapenem-resistant\n                      <jats:italic toggle=\"yes\">Acinetobacter baumannii<\/jats:italic>\n                      (CRAB) remains a major challenge in clinical practice because of limited treatment options. Zosurabalpin (ZAB) is a first-in-class macrocyclic peptide antibiotic that has been proposed as a potential therapeutic agent for CRAB infections; however, data on its\n                      <jats:italic toggle=\"yes\">in vitro<\/jats:italic>\n                      activity against clinical isolates remain limited. This study provides comprehensive\n                      <jats:italic toggle=\"yes\">in vitro<\/jats:italic>\n                      susceptibility data for ZAB against clinical CRAB isolates, including strains resistant to colistin and cefiderocol. Our findings demonstrate that ZAB retains\n                      <jats:italic toggle=\"yes\">in vitro<\/jats:italic>\n                      activity against CRAB, including isolates resistant to colistin and\/or cefiderocol, and support its potential as a promising therapeutic option for the treatment of difficult-to-treat CRAB infections.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1128\/spectrum.00318-26","type":"journal-article","created":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T13:00:20Z","timestamp":1790686820000},"update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["<i>In vitro<\/i>\n                    activities of zosurabalpin and comparator antimicrobials against clinical isolates of carbapenem-resistant\n                    <i>Acinetobacter baumannii<\/i>"],"prefix":"10.1128","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3815-6305","authenticated-orcid":true,"given":"Yu-Tzu","family":"Lin","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/0368s4g32","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Medical Laboratory Science and Biotechnology, China Medical University","place":["Taichung, Taiwan"]},{"id":[{"id":"https:\/\/ror.org\/032d4f246","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Laboratory Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hsiu-Hsien","family":"Lin","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/032d4f246","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Laboratory Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sin-Rong","family":"Li","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/032d4f246","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Laboratory Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kun-Hao","family":"Tseng","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/032d4f246","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Laboratory Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zi-Lun","family":"Lai","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/032d4f246","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Laboratory Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mao-Wang","family":"Ho","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/0368s4g32","id-type":"ROR","asserted-by":"publisher"}],"name":"Division of Infectious Diseases, Department of Internal Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7502-9225","authenticated-orcid":true,"given":"Po-Ren","family":"Hsueh","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/032d4f246","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Laboratory Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]},{"id":[{"id":"https:\/\/ror.org\/0368s4g32","id-type":"ROR","asserted-by":"publisher"}],"name":"Division of Infectious Diseases, Department of Internal Medicine, China Medical University Hospital, China Medical University","place":["Taichung, Taiwan"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","published-online":{"date-parts":[[2026,9,29]]},"reference":[{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2024.1395260"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2020.00068"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.1055\/s-0034-1398388"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.1128\/CMR.00058-16"},{"key":"e_1_3_3_6_2","doi-asserted-by":"publisher","DOI":"10.1128\/cmr.00279-24"},{"key":"e_1_3_3_7_2","first-page":"12","volume-title":"Bacterial priority pathogens list","author":"WHO","year":"2024","unstructured":"WHO. 2024. 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