{"title":"Emergence and local dissemination of NDM-14-producing <i>Klebsiella pneumoniae</i> ST147: a phylodynamic and epidemiological investigation.","authors":"Gabriele Arcari, Mattia Carbotti, Riccardo Pavesi, Paolo Gigante, Riccardo Capuano, Domenico Caleca, Angelo Paolo Genoni, Stefano Gaiarsa, Gherard Batisti Biffignandi, Angela Kuka, Federica Novazzi, Fausto Baldanti, Nicasio Mancini","doi":"10.1128/aac.00545-26","DOIUrl":"10.1128/aac.00545-26","url":null,"abstract":"<p><p>NDM-14-producing <i>Klebsiella pneumoniae</i> ST147 has recently emerged as a high-risk clone in Europe, but its local dissemination dynamics remain poorly defined. We investigated a 6-month outbreak across three hospitals within a regional healthcare network in Lombardy, Northern Italy. Among 32 NDM-producing <i>K. pneumoniae</i>, isolated between December 2024 and May 2025, 19 belonged to ST147, including one NDM-1 producer and 18 carrying NDM-14 or its A233V variant NDM-61. Phylodynamic analysis of the ST147 NDM-14/NDM-61 genomes showed they were closely related (8-91 core SNPs) and descended from a most recent common ancestor dated to June 2024 (95% highest posterior density interval, 6 months). Reconstruction of the transmission network hints at the presence of at least three transmission clusters within the healthcare system: a major chain involving 11 of 18 cases spanning wards and facilities, a separate pair of linked cases, and 5 epidemiologically unlinked cases, suggesting missed intermediates or secondary introductions. The spread was characterized by rapid local expansion of the clone across intensive care, medical, and rehabilitation. These findings underscore the propensity of NDM-14-producing ST147 to disseminate efficiently within interconnected hospitals and highlight the need for enhanced genomic surveillance, coordinated infection control strategies, and judicious use of last-resort agents in regional healthcare networks. In a global phylogenetic context, the Italian isolates clustered within a broader NDM-14 ST147 population composed of several geographically distinct clades associated with France, Italy, Spain, Morocco, and the United Kingdom.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0054526"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148705268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Trifluoperazine exhibits broad-spectrum antiviral activity against arboviruses.","authors":"Laxmi Mishra, Manjula Kalia","doi":"10.1128/aac.00100-26","DOIUrl":"10.1128/aac.00100-26","url":null,"abstract":"<p><p>The recurrent outbreaks and geographical expansion of mosquito-borne arboviruses pose a significant challenge to public health worldwide. The disease outcome for arboviral infections ranges from acute febrile illness to severe conditions such as encephalitis, hemorrhagic shock, and mortality. Current treatment options for these viruses are limited to supportive care, necessitating an urgent need for a safe and effective broad-spectrum antiviral. In this study, we have identified trifluoperazine (TFP), an FDA-approved antipsychotic, as a potent broad-spectrum antiviral against Japanese encephalitis virus (JEV), Dengue virus (DENV), and Chikungunya virus (CHIKV) infections. The antiviral effect of TFP was also seen in the animal models of JEV and CHIKV with significantly reduced disease severity. Mechanistically, TFP treatment increased the phosphorylation of eIF2a and induced an adaptive ER stress response in diverse cell types. Alleviation of TFP-induced ER stress by chemical chaperone 4PBA abolished the antiviral activity of the drug and rescued virus replication in cells and CHIKV mice model. The robust <i>in vitro</i> and <i>in vivo</i> efficacy of the drug against arboviruses highlights the potential for repurposing TFP as a broad-spectrum antiviral candidate and underscores the importance of ER stress as a therapeutic target.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0010026"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sheeba Santhini Manoharan-Basil, Tessa de Block, Izumo Kanesaka, Saïd Abdellati, Thibaut Vanbaelen, Chris Kenyon
{"title":"Extension of <i>penA</i> diversity within the genus <i>Neisseria</i>: characterization of a <i>penA/ftsI</i> homolog in <i>Neisseria bacilliformis</i> associated with elevated ceftriaxone MICs.","authors":"Sheeba Santhini Manoharan-Basil, Tessa de Block, Izumo Kanesaka, Saïd Abdellati, Thibaut Vanbaelen, Chris Kenyon","doi":"10.1128/aac.00392-26","DOIUrl":"10.1128/aac.00392-26","url":null,"abstract":"<p><p>Reduced susceptibility to extended-spectrum cephalosporins in <i>Neisseria gonorrhoeae</i> is primarily mediated by structural alterations in penicillin-binding protein 2 (PBP2), encoded by <i>penA</i>, frequently arising through interspecies recombination with commensal <i>Neisseria</i>. While mosaic <i>penA</i> diversity has been extensively characterized in coccoid <i>Neisseria</i> species, rod-shaped commensals such as <i>Neisseria bacilliformis</i> remain poorly explored. Here, we investigated the β-lactam target repertoire of <i>N. bacilliformis</i> using whole-genome sequencing, comparative genomics, mutation profiling, and structural modeling. Fifteen <i>N. bacilliformis</i> genomes were analyzed, including eight isolates with elevated ceftriaxone minimum inhibitory concentrations (MIC) (range 0.094-1 µg/mL; median 0.5 µg/mL). Interrogation of the PubMLST locus NEIS1753 did not identify matches under default parameters. However, <i>de novo</i> annotation revealed a syntenic high-molecular-mass transpeptidase annotated as <i>ftsI</i>, occupying the conserved <i>rsmH-ftsL-ftsI-murE</i> chromosomal context observed in <i>N. gonorrhoeae</i>. BLASTP analysis demonstrated ~59%-61% amino-acid identity to gonococcal PBP2. Structural modeling using AlphaFold and template-based approaches confirmed preservation of the canonical class B penicillin-binding protein fold, including conserved catalytic motifs. Across 24 positions previously associated with altered cephalosporin susceptibility in gonococci, multiple canonical substitutions were conserved in <i>N. bacilliformis</i>, alongside lineage-specific variants not reported in <i>N. gonorrhoeae</i>. Interestingly, polymorphism at positions A328 and A341 was observed in isolates with higher MICs (1 µg/mL). Definitive genotype-phenotype associations could not be established. Recombination analysis did not identify discrete parental donors but suggested a complex evolutionary history. These findings demonstrate that <i>N. bacilliformis</i> encodes a structurally conserved PBP2 homolog annotated as FtsI and expand the landscape of β-lactam target diversity within the genus <i>Neisseria</i>.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0039226"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bharath Reddy Boya, Ezhaveni Sathiyamoorthi, Jin-Hyung Lee, Jintae Lee
{"title":"Antifungal activity of the nucleoside mimetic 5-fluorouridine against <i>Candidozyma auris</i> and <i>Candida</i> species.","authors":"Bharath Reddy Boya, Ezhaveni Sathiyamoorthi, Jin-Hyung Lee, Jintae Lee","doi":"10.1128/aac.00027-26","DOIUrl":"10.1128/aac.00027-26","url":null,"abstract":"<p><p>The emergence of multidrug-resistant <i>Candidozyma auris</i> has created an urgent need for antifungals with novel mechanisms of action. We screened 121 nucleoside and nucleobase derivatives against <i>C. auris</i> and other clinically relevant <i>Candida</i> species to identify effective antimetabolite scaffolds. Among all compounds tested, only the C-5-fluorinated nucleosides 5-fluorouridine (5-FU) and 5-fluorocytidine exhibited potent antifungal activity. 5-FU demonstrated consistently low minimum inhibitory concentrations (0.5-10 µg/mL) across multiple <i>Candida</i> species, including fluconazole-resistant strains, and displayed fungicidal activity against <i>C. auris</i> at concentrations lower than several frontline antifungals. Uridine rescue assays confirmed competitive interference with endogenous uridine metabolism. Checkerboard assays revealed synergistic or additive interactions between 5-FU and clinically used azoles and echinocandins. Toxicity evaluation using plant, nematode, and human cell models showed minimal cytotoxicity even at concentrations far exceeding antifungal minimum inhibitory concentrations. <i>In silico</i> docking analyses revealed dual inhibition of thymidylate synthase and RNA polymerase III, explaining the fungicidal phenotype and broad-spectrum efficacy. These findings identify 5-fluorouridine as a promising antifungal candidate and establish C-5-halogenated nucleosides as a privileged scaffold for antifungal drug development.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0002726"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148764150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pharmacokinetics of injectable favipiravir: phase I, randomized, double-blind, placebo-controlled study in healthy East Asian subjects.","authors":"Hiroshige Mikamo, Masahiro Nakabayashi, Tsutomu Sakurai","doi":"10.1128/aac.00463-26","DOIUrl":"10.1128/aac.00463-26","url":null,"abstract":"<p><p>Favipiravir, an oral antiviral medication, has been approved in Japan for the treatment of patients with novel or re-emerging influenza and severe fever with thrombocytopenia syndrome (SFTS). Randomized, double-blind, placebo-controlled trials were conducted in an East Asian population to characterize the pharmacokinetics and tolerability of an injectable favipiravir formulation. In the single-ascending dose trial, subjects received a single intravenous (IV) dose of 300-2,400 mg of favipiravir. In the multiple dose trial, 1,800 mg was administered twice daily on the first day, followed by 800 mg twice daily for the subsequent 10 days, which is the approved tablet dose for SFTS in Japan. This multiple-dose trial was divided into a cohort receiving intravenous administration throughout the treatment period (IV cohort) and a cohort switching to oral administration from Day 6 (Switching cohort). After a single administration of ≤2,400 mg, the pharmacokinetic parameters increased in a dose-dependent manner but showed slight deviation from linearity. The geometric mean maximum plasma concentration following a single 2,400 mg dose was 126 (range: 110 to 138) μg/mL. In the IV cohort, the trough (at 12 h post-dose) plasma concentrations were maintained at approximately 85 μg/mL after Day 2. These concentrations were approximately 20% higher than those achieved with the same oral doses. In the Switching cohort, these concentrations were maintained throughout the treatment. No serious adverse events were observed. These findings support advancing injectable favipiravir into clinical evaluation.CLINICAL TRIALSThis study is registered with the Japan Registry of Clinical Trials as jRCT2071210042 and jRCT2071210126.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0046326"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148534961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kai-Su Pan, Ying-Gai Song, Sha Lu, Xiao-Fang Li, Huai-Qiu Huang, Jie Gong, Ruo-Yu Li, Hai-Lin Zheng, Miao-Rong Zhan, Shu Zhang, Xin-Yu Zhou, Yuan-Yuan Geng, Si-Wen Jiang, Sheng-Xiu Fang, Yanqing Zheng, Dong-Yan Zheng, Weixuan Wu, Li-Yan Xi, He-Ping Xu, Paul E Verweij, Cun-Wei Cao
{"title":"Establishment of epidemiological cutoff values for yeast-phase <i>Talaromyces marneffei</i> against six antifungal agents: a multicenter study in China.","authors":"Kai-Su Pan, Ying-Gai Song, Sha Lu, Xiao-Fang Li, Huai-Qiu Huang, Jie Gong, Ruo-Yu Li, Hai-Lin Zheng, Miao-Rong Zhan, Shu Zhang, Xin-Yu Zhou, Yuan-Yuan Geng, Si-Wen Jiang, Sheng-Xiu Fang, Yanqing Zheng, Dong-Yan Zheng, Weixuan Wu, Li-Yan Xi, He-Ping Xu, Paul E Verweij, Cun-Wei Cao","doi":"10.1128/aac.00650-26","DOIUrl":"10.1128/aac.00650-26","url":null,"abstract":"<p><p>This study aimed to establish epidemiological cutoff values (ECVs) for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, and isavuconazole against <i>Talaromyces marneffei</i> (<i>T. marneffei</i>) using the CLSI broth microdilution method. Antifungal susceptibility testing of 207 <i>T. marneffei</i> isolates was performed independently at five laboratories across China according to CLSI M27-A4 guidelines. Minimum inhibitory concentration (MIC) distributions were analyzed using ECOFFinder software (version 2.1), and ECVs were set at the upper MIC limit encompassing 97.5% of the modeled wild-type (WT) population. ECVs were determined as follows: amphotericin B (AMB) 8 µg/mL, voriconazole (VRC) 0.03 µg/mL, itraconazole (ITC) 0.125 µg/mL, posaconazole (POS) 0.06 µg/mL, isavuconazole (ISA) 0.125 µg/mL, and fluconazole (FLC) 8 µg/mL. MIC distributions for all six agents conformed well to the fitted models (normal or log-normal), supporting the validity of ECV determination. No non-WT isolates were detected for amphotericin B, whereas non-WT rates for azoles were 15.5% (voriconazole), 8.45% (itraconazole), 6.37% (posaconazole), 3.0% (fluconazole), and 1.02% (isavuconazole). Among voriconazole non-WT isolates, all were from patients with prior voriconazole exposure. This study provides the first standardized ECVs for <i>T. marneffei</i> against six key antifungal agents. The data establish a reference framework for antifungal susceptibility testing and resistance surveillance and highlight the need for continued monitoring of azole susceptibility in this pathogen.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0065026"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148676769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jacques Rossouw, Robert Wallis, Hardy Kornfeld, Amit Singhal, Gary Maartens, Lubbe Wiesner, Paolo Denti, Roeland E Wasmann
{"title":"The effect of metformin on the pharmacokinetics of rifampicin, isoniazid, and pyrazinamide in adults with tuberculosis.","authors":"Jacques Rossouw, Robert Wallis, Hardy Kornfeld, Amit Singhal, Gary Maartens, Lubbe Wiesner, Paolo Denti, Roeland E Wasmann","doi":"10.1128/aac.00748-26","DOIUrl":"10.1128/aac.00748-26","url":null,"abstract":"<p><p>Metformin is under investigation as adjunctive host-directed therapy for tuberculosis (TB), which might interact with first-line TB treatment. We used population pharmacokinetic modeling to assess whether metformin alters first-line TB-drug pharmacokinetics in HIV/TB-coinfected adults without diabetes. Rifampicin, isoniazid, and pyrazinamide pharmacokinetics were investigated in participants from a randomized clinical trial of adjunctive metformin (500 mg twice daily to week 12) in adults starting HIV-associated TB treatment. Antiretroviral therapy (ART)-naïve participants initiated dolutegravir-based ART within 8 weeks. Intensive and semi-intensive sampling was conducted at week 5; concentration-time data were analyzed using non-linear mixed-effects modeling. Data from 78 individuals (43 receiving metformin, median weight 60.8 kg, 62.8% male, 79.5% on ART) were analyzed. Rifampicin and pyrazinamide were described by one-compartment models with linear elimination; typical clearances were 15.8 L/h (95% CI: 13.5-18.7) and 3.88 L/h (95% CI: 3.54-4.08), respectively. Isoniazid followed a two-compartment model with a mixture model for acetylator status; clearance was 10.5 L/h (95% CI: 9.44-11.9) in slow acetylators and 28.8 L/h (95% CI: 25.6-31.0) in fast/intermediate acetylators. Metformin reduced isoniazid bioavailability by 15.6% (95% CI: 4.45-26.4%, <i>P</i> < 0.009) and rifampicin bioavailability by 24.0% (95% CI: 7.83-36.3%, <i>P</i> < 0.007), decreasing the area under the curve from 0 to 24 h from 18.2 to 15.6 mg·h/L and from 35.9 to 27.1 mg·h/L, respectively. No significant effect on pyrazinamide was detected. We found that non-diabetic patients on metformin had lower isoniazid and rifampicin bioavailability. Lowered rifampicin exposure might be clinically relevant; simulations suggest that this could be offset by a single 150 mg rifampicin dose.CLINICAL TRIALSThis study is registered with ClinicalTrials.gov as NCT04930744.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0074826"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148676844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhichen Zhu, Tengfei Long, Bingjie Wang, Weijia Ding, Yuxin Yan, Yicheng Wen, Yapin Zhao, Jie Zhu, Liang Wang, Jinnan Lv, Barry N Kreiswirth, Hong Du, Liang Chen
{"title":"Genome-wide transposon screening uncovers phage resistance mechanisms and bidirectional effects on antibiotic susceptibility in carbapenem-resistant <i>Klebsiella pneumoniae</i>.","authors":"Zhichen Zhu, Tengfei Long, Bingjie Wang, Weijia Ding, Yuxin Yan, Yicheng Wen, Yapin Zhao, Jie Zhu, Liang Wang, Jinnan Lv, Barry N Kreiswirth, Hong Du, Liang Chen","doi":"10.1128/aac.00506-26","DOIUrl":"10.1128/aac.00506-26","url":null,"abstract":"<p><p>Phage therapy and phage-antibiotic combinations are promising strategies against multidrug-resistant pathogens like carbapenem-resistant <i>Klebsiella pneumoniae</i> (CRKP). However, the mechanisms underlying phage resistance and the molecular basis of the rational design of phage-antibiotic combinations require further investigation. Using genome-wide transposon screening, CRISPR-Cas9 knockout, and plasmid complementation in a clinical ST11-KL64 CRKP strain, we investigated susceptibility determinants for phage P545 and their impact on antibiotic susceptibility. We identified multiple phage resistance mechanisms, including disruption of phage receptor lipopolysaccharide (LPS) biosynthesis genes (involving deletions of <i>waaQ</i>, <i>wabH</i>, <i>wabG</i>, <i>ugd</i>, <i>galU</i>, and <i>wcaG</i>), inhibition of phage burst through an undefined pathway (involving deletion of <i>sirB1</i>), and increased mutation frequency (involving deletions of <i>mutS</i> and <i>mutL</i>). Furthermore, we found that deletions of LPS-related genes reduced resistance to multiple antibiotics, while <i>mutS</i> and <i>mutL</i> deletions increased resistance to several antibiotics. Further synergy assays showed that P545 in combination with meropenem, colistin, or ceftazidime had synergistic effects in the <i>in vitro</i> killing of host bacteria. By integrating genetic screening and functional validation, our approach offers a versatile platform for dissecting phage targets, understanding resistance mechanisms, and evaluating phage-antibiotic interactions. These findings provide valuable tools and insights for optimizing phage-phage and phage-antibiotic combination therapies against clinically significant multidrug-resistant pathogens.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0050626"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148676778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alex E Clark, Jonathan R Erlich, James R Beadle, Rachel E McMillan, Jialei Xie, Aaron F Garretson, Shae Atkins, Anoushka Sharma, Suraj Manohar Rajan, Ben A Croker, Robert T Schooley, Karl Y Hostetler, Aaron F Carlin
{"title":"Oral lipid prodrug V2043 (1-<i>O</i>-octadecyl-2-<i>O</i>-benzyl-<i>sn</i>-glyceryl-P-remdesivir nucleoside) protects mice from lethal dengue infection.","authors":"Alex E Clark, Jonathan R Erlich, James R Beadle, Rachel E McMillan, Jialei Xie, Aaron F Garretson, Shae Atkins, Anoushka Sharma, Suraj Manohar Rajan, Ben A Croker, Robert T Schooley, Karl Y Hostetler, Aaron F Carlin","doi":"10.1128/aac.00401-26","DOIUrl":"10.1128/aac.00401-26","url":null,"abstract":"<p><p>Dengue virus and related flaviviruses are significant threats to global health, with no approved antiviral treatments available. Remdesivir triphosphate (RVn-TP) is a nucleotide analog that inhibits RNA-dependent RNA polymerases from many clinically important RNA viruses, including dengue virus. An orally bioavailable prodrug that efficiently delivers RVn-TP could facilitate early treatment for non-hospitalized dengue patients. To that end, we developed 1-<i>O</i>-octadecyl-2-<i>O</i>-benzyl-<i>sn</i>-glyceryl-P-remdesivir nucleoside (V2043, ODBG-P-RVn), a phospholipid prodrug that achieves RVn-TP delivery through improved oral bioavailability, potency, and pharmacokinetics. Here, we show that when compared to the parent compound remdesivir nucleoside (RVn), V2043 is a more potent <i>in vitro</i> inhibitor of multiple flaviviruses, including dengue, Zika, West Nile, and Japanese encephalitis viruses. In lethal prophylactic and therapeutic mouse models that recapitulate key aspects of severe dengue in humans, once-daily oral V2043 significantly decreased dengue serum viremia, clinical severity, weight loss, and mortality. Additionally, oral V2043 was well tolerated when administered daily for 14 days. These results demonstrate the potential therapeutic efficacy of V2043 to treat several clinically relevant flaviviruses, including dengue virus, the most prevalent and widespread arbovirus infection in the world.</p>","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0040126"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13604564/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148663493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shubhendu Bajpai, Abdullah Sultany, Kevin Carroll, Rahul Zain, Apurwa Karki
{"title":"Selective digestive decontamination and antimicrobial resistance: defining thresholds before global implementation.","authors":"Shubhendu Bajpai, Abdullah Sultany, Kevin Carroll, Rahul Zain, Apurwa Karki","doi":"10.1128/aac.00681-26","DOIUrl":"10.1128/aac.00681-26","url":null,"abstract":"","PeriodicalId":8152,"journal":{"name":"Antimicrobial Agents and Chemotherapy","volume":" ","pages":"e0068126"},"PeriodicalIF":4.2,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148534976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}