{"id":104,"date":"2023-08-29T13:14:44","date_gmt":"2023-08-29T13:14:44","guid":{"rendered":"https:\/\/www.merckconnect.com\/zerbaxa\/?page_id=104"},"modified":"2026-04-09T12:13:25","modified_gmt":"2026-04-09T12:13:25","slug":"clinical-efficacy-cuti","status":"publish","type":"page","link":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/","title":{"rendered":"Clinical efficacy against cUTIs"},"content":{"rendered":"<link rel='stylesheet' id='vivid360-heading-css-css' href='https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/themes\/cex-wpvip-mhh-merck-vivid360-theme-1-12\/blocks\/heading\/css\/style.min.css?ver=1765535927' media='all' \/>\n\n<div class=\"vivid360-heading\" id=\"afdb8a009-b4fb-4dcb-8bcc-20647ad38d3b\"><h1 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:36px;--tabletFontSize:36px;--mobileFontSize:24px;--desktopLineHeightSize:45px;--tabletLineHeightSize:45px;--mobileLineHeightSize:\" id=\"top\"><strong>Clinical efficacy of ZERBAXA\u00ae (ceftolozane and tazobactam) against cUTIs<\/strong><\/h1><\/div>\n\n\n<link rel='stylesheet' id='vivid360-spacer-css-css' href='https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/themes\/cex-wpvip-mhh-merck-vivid360-theme-1-12\/blocks\/spacer\/css\/style.min.css?ver=1765535928' media='all' \/>\n\n<div style=\"background-color:transparent;--desktop-spacer:24px;--tablet-spacer:24px;--mobile-spacer:24px;height:24px\" class=\"wp-block-vivid360-spacer vivid360-spacer-desktop vivid360-spacer-tablet vivid360-spacer-mobile\"><\/div>\n\n\n\n<div class=\"vivid360-heading default-hcp-fontsize default-hcp-tablet-fontsize default-hcp-mobile-fontsize\" id=\"aa2c8777d-1aa7-411b-8373-d0e63d0e5b20\"><h2 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:var(--h2FontSizeDesktop);--tabletFontSize:var(--h2FontSizeDesktop);--mobileFontSize:var(--h2FontSizeMobile);--desktopLineHeightSize:var(--h2LineHeightDesktop);--tabletLineHeightSize:var(--h2LineHeightDesktop);--mobileLineHeightSize:\" id=\"\"><strong>Learn about:<\/strong><\/h2><\/div>\n\n\n<link rel='stylesheet' id='vivid360-list-css-css' href='https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/themes\/cex-wpvip-mhh-merck-vivid360-theme-1-12\/blocks\/list\/css\/style.min.css?ver=1765535927' media='all' \/>\n\n<div class=\"vivid-block-list content-width has-dark-text-color default-list block-d536e8a5-fed9-4c9a-b131-2821e304052b custom-colored-hyperlink\" data-image=\"\" data-image-mobile=\"\" data-image-all=\"\" data-image-all-mobile=\"\" data-icon-color=\"#333\" data-text-color=\"#bf5411\" data-client-id=\"block-d536e8a5-fed9-4c9a-b131-2821e304052b\"><ul class=\"first-level\"><li><em><a href=\"#cUTIadult\">cUTI in adult patients<\/a><\/em><\/li><li><em><a href=\"#cUTIpediatric\">cUTI in pediatric patients<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid360-heading\" id=\"a1fd75c88-4c76-46a8-b30c-9d3541c79309\"><h3 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:var(--h3FontSizeDesktop);--tabletFontSize:var(--h3FontSizeDesktop);--mobileFontSize:var(--h3FontSizeMobile);--desktopLineHeightSize:var(--h3LineHeightDesktop);--tabletLineHeightSize:var(--h3LineHeightDesktop);--mobileLineHeightSize:\" id=\"cUTIadult\"><strong>Complicated urinary tract infections (cUTIs) in adult patients, including pyelonephritis<\/strong><\/h3><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>A total of 1068 adults hospitalized with cUTI (including pyelonephritis) were randomized and received study medications in a multinational, double-blind study comparing ZERBAXA <span class=\"no-wrap-text\">1.5 g<\/span> (ceftolozane <span class=\"no-wrap-text\">1 g<\/span> and tazobactam <span class=\"no-wrap-text\">0.5 g<\/span>) intravenously every 8 hours to levofloxacin (<span class=\"no-wrap-text\">750 mg<\/span> intravenously once daily) for <span class=\"no-wrap-text\">7 days<\/span> of therapy.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The primary efficacy endpoint was defined as complete resolution or marked improvement of the clinical symptoms and microbiological eradication (all uropathogens found at baseline at \u226510<sup>5<\/sup>&nbsp;were reduced to &lt;10<sup>4<\/sup>&nbsp;CFU\/mL) at the test-of-cure (TOC) visit 7 (\u00b1 2) days after the last dose of study drug.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The primary efficacy analysis population was the microbiologically modified intent-to-treat (mMITT) population, which included all patients who received study medication and had at least 1 baseline uropathogen. The key secondary efficacy endpoint was the composite microbiological and clinical cure response at the TOC visit in the microbiologically evaluable (ME) population, which included protocol-adherent mMITT patients with a urine culture at the TOC visit.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The mMITT population consisted of 800 patients with cUTI, including 656 (82%) with pyelonephritis. The median age was 50.5 years and 74% were female. Concomitant bacteremia was identified in 62 (7.8%) patients at baseline; 608 (76%) patients were enrolled in Eastern Europe and 14 (1.8%) patients were enrolled in the United States.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>ZERBAXA demonstrated efficacy with regard to the composite endpoint of microbiological and clinical cure at the TOC visit in both the mMITT and ME populations (table below). Composite microbiological and clinical cure rates at the TOC visit by pathogen in the mMITT population are presented in the table below.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>In the mMITT population, the composite cure rate in ZERBAXA-treated patients with concurrent bacteremia at baseline was 23\/29 (79.3%).<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>Although a statistically significant difference was observed in the ZERBAXA arm compared to the levofloxacin arm with respect to the primary endpoint, it was likely attributable to the 212\/800 (26.5%) patients with baseline organisms non-susceptible to levofloxacin. Among patients infected with a levofloxacin-susceptible organism at baseline, the response rates were similar (table below).<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid360-heading\" id=\"ad5cd8fe4-cb69-40a7-9aa1-9649067c779c\"><h3 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:var(--h3FontSizeDesktop);--tabletFontSize:var(--h3FontSizeDesktop);--mobileFontSize:var(--h3FontSizeMobile);--desktopLineHeightSize:var(--h3LineHeightDesktop);--tabletLineHeightSize:var(--h3LineHeightDesktop);--mobileLineHeightSize:\" id=\"\">Composite microbiological and clinical cure rates in a Phase 3 trial of complicated urinary tract infections in adult patients<\/h3><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"wp-block-columns mb-0 is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column mb-0 is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:65%\">\n<div style=\"background-color:transparent;height:16px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-16\"><\/div>\n\n\n\n<figure class=\"wp-block-flexible-table-block-table is-scroll-on-mobile mb-0\"><table class=\"\"><thead><tr><th style=\"background-color:#bf5411;color:#FFF;border-width:1px;text-align:center;border-color:#435363 #FFF #435363 #435363\"><span class=\"no-wrap-text\">Analysis<\/span> <span class=\"no-wrap-text\">population<\/span><\/th><th style=\"background-color:#bf5411;color:#FFF;border-width:1px;text-align:center;border-color:#435363 #FFF #435363 #435363\"><span class=\"no-wrap-text\">ZERBAXA<sup>a<\/sup><\/span><br>n\/N (%)<\/th><th style=\"background-color:#bf5411;color:#FFF;border-width:1px;text-align:center;border-color:#435363 #FFF #435363 #435363\"><span class=\"no-wrap-text\">Levofloxacin<sup>b<\/sup><\/span><br>n\/N (%)<\/th><th style=\"background-color:#bf5411;color:#FFF;border-width:1px;text-align:center;border-color:#435363\"><span class=\"no-wrap-text\">Treatment<\/span><br><span class=\"no-wrap-text\">difference<\/span> <br>(95% CI)<sup>c<\/sup><\/th><\/tr><\/thead><tbody><tr><td style=\"text-align:center;color:#000;border-color:#435363\"><strong>mMITT<\/strong><\/td><td style=\"text-align:center;color:#000;border-color:#435363\">306\/398 (76.9)<\/td><td style=\"text-align:center;color:#000;border-color:#435363\">275\/402 (68.4)<\/td><td style=\"text-align:center;color:#000;border-color:#435363\">8.5 (2.3, 14.6)<\/td><\/tr><tr><td style=\"text-align:center;color:#000;border-color:#435363\"><span class=\"no-wrap-text\">Levofloxacin<\/span> resistant<br>baseline <span class=\"no-wrap-text\">pathogen(s)<\/span><\/td><td style=\"text-align:center;color:#000;border-color:#435363\">60\/100 (60)<\/td><td style=\"text-align:center;color:#000;border-color:#435363\">44\/112 (39.3)<\/td><td style=\"background-color:#e6e7e8;text-align:center;color:#000;border-width:1px;border-color:#435363 #435363 #e6e7e8\"><\/td><\/tr><tr><td style=\"text-align:center;color:#000;border-color:#435363\">No <span class=\"no-wrap-text\">levofloxacin<\/span> resistant<br>baseline <span class=\"no-wrap-text\">pathogen(s)<\/span><\/td><td style=\"text-align:center;color:#000;border-color:#435363\">246\/298 (82.6)<\/td><td style=\"text-align:center;color:#000;border-color:#435363\">231\/290 (79.7)<\/td><td style=\"background-color:#e6e7e8;text-align:center;color:#000;border-color:#435363\"><\/td><\/tr><tr><td style=\"text-align:center;color:#000;border-color:#435363\"><strong>ME<\/strong><\/td><td style=\"text-align:center;color:#000;border-color:#435363\">284\/341 (83.3)<\/td><td style=\"text-align:center;color:#000;border-color:#435363\">266\/353 (75.4<\/td><td style=\"text-align:center;color:#000;border-color:#435363\">8.0 (2.0, 14.0)<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:35%\"><\/div>\n<\/div>\n\n\n\n<div class=\"paragraph-wrapper\"><div class=\"_bae4e909-0af9-49e4-abe7-6c41d8078d8d has-small-font-size\" id=\"\"><p><sup>a<\/sup>ZERBAXA 1.5 g intravenously every 8 hours.<br><span class=\"no-wrap-text\"><sup>b<\/sup>750 mg<\/span> intravenously once daily.<br><sup>c<\/sup>The 95% confidence interval was based on the stratified Newcombe method.<\/p><\/div><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid360-heading\" id=\"a80084798-6070-494e-8913-2a4027c91eb5\"><h3 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:var(--h3FontSizeDesktop);--tabletFontSize:var(--h3FontSizeDesktop);--mobileFontSize:var(--h3FontSizeMobile);--desktopLineHeightSize:var(--h3LineHeightDesktop);--tabletLineHeightSize:var(--h3LineHeightDesktop);--mobileLineHeightSize:\" id=\"\">Composite microbiological and clinical cure rates in a Phase 3 trial of complicated urinary tract infections, in subgroups defined by baseline pathogen (mMITT population)<\/h3><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-vertically-aligned-top is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:70%\">\n<figure class=\"wp-block-flexible-table-block-table mb-0\"><table class=\"has-fixed-layout\"><tbody><tr><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363 #FFF #435363 #435363;border-width:1px 1px 0;width:38%\"><strong>Pathoge<\/strong>n<\/td><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363 #FFF #435363 #435363;border-width:1px 1px 0;width:30%;text-align:center\"><strong>ZERBAXA<br><span class=\"no-wrap-text\">n\/N (%)<\/span><\/strong><\/td><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363;border-width:1px 1px 0;width:32%;text-align:center\"><strong><span class=\"no-wrap-text\">Levofloxacin<\/span><br><span class=\"no-wrap-text\">n\/N (%)<\/span><\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n<link rel='stylesheet' id='vivid360-table-css-css' href='https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/themes\/cex-wpvip-mhh-merck-vivid360-theme-1-12\/blocks\/table\/css\/style.min.css?ver=6.8.5' media='all' \/>\n<link rel='stylesheet' id='vivid360-table-sortable-css-css' href='https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/themes\/cex-wpvip-mhh-merck-vivid360-theme-1-12\/blocks\/table\/css\/sortable.min.css?ver=6.8.5' media='all' \/>\n\n<figure class=\"wp-block-vivid360-table content-width mt-0\"><table id=\"a01d504a7-8578-4ac6-850b-676cbc76b4d6-vivid360-table-id\" class=\"a01d504a7-8578-4ac6-850b-676cbc76b4d6 squished has-fixed-layout\" style=\"--tableBorder:1px solid #435363;--tableBorderRadius:0\" role=\"grid\"><tbody><tr style=\"background-color:#fff\"><td class=\"has-text-align-left has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"left\" width=\"38%\"><em>Escherichia coli<\/em><\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"30%\">247\/305 (81)<\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"32%\">228\/324 (70.4)<\/td><\/tr><tr style=\"background-color:#e6e7e8\"><td class=\"has-text-align-left has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"left\" width=\"38%\"><em>Klebsiella <span class=\"no-wrap-text\">pneumoniae<\/span><\/em><\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"30%\">22\/33 (66.7)<\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"32%\">12\/25 (48)<\/td><\/tr><tr style=\"background-color:#fff\"><td class=\"has-text-align-left has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"left\" width=\"38%\"><em>Proteus mirabilis<\/em><\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"30%\">11\/12 (91.7)<\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"32%\">6\/12 (50)<\/td><\/tr><tr style=\"background-color:#e6e7e8\"><td class=\"has-text-align-left has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"left\" width=\"38%\"><em><span class=\"no-wrap-text\">Pseudomonas<\/span> aeruginosa<\/em><\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"30%\">6\/8 (75)<\/td><td class=\"has-text-align-center has-black-color has-regular-font-size\" style=\"color:undefined!important\" data-align=\"center\" width=\"32%\">7\/15 (46.7)<\/td><\/tr><\/tbody><\/table><div class=\"\"><small class=\"table-caption\"><\/small><\/div><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-top is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:30%\"><\/div>\n<\/div>\n\n\n\n<p>In a subset of the&nbsp;<em>E. coli<\/em>&nbsp;and&nbsp;<em>K. pneumoniae<\/em>&nbsp;isolates from both arms of the cUTI Phase 3 trial that met pre-specified criteria for beta-lactam susceptibility, genotypic testing identified certain ESBL groups (e.g., TEM, SHV, CTX-M, OXA) in 104\/687 (15%). Cure rates in this subset were similar to the overall trial results.&nbsp;In vitro&nbsp;susceptibility testing showed that some of these isolates were susceptible to ZERBAXA (MIC \u22642 mcg\/mL), while some others were not susceptible (MIC &gt;<span class=\"no-wrap-text\">2 mcg\/mL<\/span>). Isolates of a specific genotype were seen in patients who were deemed to be either successes or failures.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid-block-list content-width  use-image-all block-4051013e-1a04-4877-a101-fbc7dcf145d4 custom-colored-hyperlink\" data-image=\"\" data-image-mobile=\"\" data-image-all=\"\" data-image-all-mobile=\"\" data-icon-color=\"#333\" data-text-color=\"#333\" data-client-id=\"block-4051013e-1a04-4877-a101-fbc7dcf145d4\"><ul class=\"first-level\"><li><em><a href=\"#top\">Back to top<\/a><\/em><\/li><li><em><a href=\"#cUTIadult\">cUTI in adult patients<\/a><\/em><\/li><li><em><a href=\"#cUTIpediatric\">cUTI in pediatric patients<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid360-heading\" id=\"a52e627d2-039f-4517-87d8-cc9b1fdaa36a\"><h3 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:var(--h3FontSizeDesktop);--tabletFontSize:var(--h3FontSizeDesktop);--mobileFontSize:var(--h3FontSizeMobile);--desktopLineHeightSize:var(--h3LineHeightDesktop);--tabletLineHeightSize:var(--h3LineHeightDesktop);--mobileLineHeightSize:\" id=\"cUTIpediatric\"><strong>Complicated urinary tract infections (cUTIs) in pediatric patients, including pyelonephritis<\/strong><\/h3><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The cUTI pediatric trial was a randomized, double-blind multi-center, active controlled trial conducted in hospitalized patients from birth to less than 18 years (NCT03230838). Eligible patients were randomized in a 3:1 ratio to IV ZERBAXA or meropenem, respectively. Patients received IV study treatment for a minimum of 3 days before an optional switch to oral step-down therapy at the discretion of the investigator to complete a total of 7 to 14 days of antibacterial therapy.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The microbiologic modified intent-to-treat (mMITT) population consisted of 95 patients (N=71 in the ZERBAXA group; N=24 in the meropenem group) who were randomized and received at least one dose of study treatment and had an eligible uropathogen isolated from a baseline urine culture.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The median age of patients was 2.7 years and 1.6 years in the ZERBAXA and meropenem groups, respectively. In the ZERBAXA group, enrollment by age group was as follows: 12 to &lt;18 y: n=10, <span class=\"no-wrap-text\">6 to &lt;12 y: n=13,<\/span> 2 to &lt;6 y: n=14, 3 months to &lt;2 y: n=20, birth to &lt;3 months: n=14. Patients treated with ZERBAXA were predominantly female (56%) and White (99%). Patients treated with meropenem were predominantly female (63%) and White (100%). Most patients in the mMITT population had a diagnosis of pyelonephritis (ZERBAXA: 84.5%; meropenem: 79.2%). The most common baseline qualifying gram-negative uropathogens were&nbsp;<em>Escherichia coli<\/em>&nbsp;(ZERBAXA: 74.6%; meropenem: 87.5%),&nbsp;<em>Klebsiella pneumoniae<\/em>&nbsp;(8.5%; 4.2%), and&nbsp;<em>Pseudomonas aeruginosa<\/em>&nbsp;(7.0%; 8.3%).<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<p>The primary objective of the study was to evaluate the safety and tolerability of ZERBAXA. Efficacy assessments were not powered for formal hypothesis testing of between treatment group comparisons. At the TOC visit, which occurred 7 to 14 days after the last dose of study drug, a favorable clinical response was defined as complete resolution or marked improvement in signs and symptoms of the cUTI or return to pre-infection signs and symptoms, such that no further antibiotic therapy (IV or oral) was required for the treatment of the cUTI. A favorable microbiological response at the TOC was defined as eradication (all uropathogens found at baseline at \u226510<sup>5<\/sup>&nbsp;were reduced to &lt;10<sup>4<\/sup>&nbsp;CFU\/mL) of baseline uropathogens from the urine culture. A summary of clinical and microbiologic response rates in the mMITT population at the TOC visit is presented in the table below.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid360-heading\" id=\"a463e97ec-76b8-43d2-97d5-a957a79c0891\"><h3 class=\"content-width fontWeightRegular\" style=\"--desktopFontSize:var(--h3FontSizeDesktop);--tabletFontSize:var(--h3FontSizeDesktop);--mobileFontSize:var(--h3FontSizeMobile);--desktopLineHeightSize:var(--h3LineHeightDesktop);--tabletLineHeightSize:var(--h3LineHeightDesktop);--mobileLineHeightSize:\" id=\"\">Clinical and microbiological response rates in a pediatric study of complicated urinary tract infections<\/h3><\/div>\n\n\n\n<div class=\"wp-block-columns mb-0 is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-vertically-aligned-top is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:70%\">\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<figure class=\"wp-block-flexible-table-block-table is-scroll-on-mobile mb-0\"><table class=\"\"><tbody><tr><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363 #FFF #435363 #435363;border-width:1px 1px 0;width:26%\"><strong>mMITT <span class=\"no-wrap-text\">population<\/span><\/strong><\/td><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363 #FFF #435363 #435363;border-width:1px 1px 0;text-align:center;width:25%\"><span class=\"no-wrap-text\"><strong>ZERBAXA<br>n\/N (%)<\/strong><\/span><\/td><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363 #FFF #435363 #435363;border-width:1px 1px 0;text-align:center;width:23%\"><strong><span class=\"no-wrap-text\">Meropenem<\/span><br><span class=\"no-wrap-text\">n\/N (%)<\/span><\/strong><\/td><td style=\"color:#FFF;background-color:#bf5411;border-color:#435363;border-width:1px 1px 0;text-align:center;width:26%\"><strong><span class=\"no-wrap-text\">Treatment<\/span><\/strong> <strong><span class=\"no-wrap-text\">difference<\/span><br><span class=\"no-wrap-text\">(95% CI)<sup>d<\/sup><\/span><\/strong><\/td><\/tr><tr><td style=\"color:#000;text-align:left;border-color:#FFF #435363 #435363\">Clinical <span class=\"no-wrap-text\">Response<\/span> Rate<\/td><td style=\"color:#000;text-align:center;border-color:#FFF #435363 #435363\">63\/71 (88.7)<\/td><td style=\"color:#000;text-align:center;border-color:#FFF #435363 #435363\">23\/24 (95.8)<\/td><td style=\"color:#000;text-align:center;border-color:#FFF #435363 #435363\">-7.3 (-18.0, 10.1)<\/td><\/tr><tr><td style=\"background-color:#e6e7e8;color:#000;text-align:left;border-color:#435363\"><span class=\"word-break\"><span class=\"no-wrap-text\">Microbiologic<\/span><\/span> <span class=\"no-wrap-text\">Response<\/span> Rate<\/td><td style=\"background-color:#e6e7e8;color:#000;text-align:center;border-color:#435363\">60\/71 (84.5)<\/td><td style=\"background-color:#e6e7e8;color:#000;text-align:center;border-color:#435363\">21\/24 (87.5)<\/td><td style=\"background-color:#e6e7e8;color:#000;text-align:center;border-color:#435363\">-3.0 (-17.1, 17.4)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-top is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:30%\"><\/div>\n<\/div>\n\n\n\n<p class=\"has-small-font-size\"><sup>d<\/sup>The Miettinen &amp; Nurminen method stratified by age group with Cochran-Mantel-Haenszel weights was used.<\/p>\n\n\n\n<div style=\"background-color:transparent;height:8px\" class=\"wp-block-vivid360-spacer vivid360-spacer spacer-8\"><\/div>\n\n\n\n<div class=\"vivid-block-list content-width  use-image-all block-c5314950-35ed-4321-a2e7-a4dcf90f85be custom-colored-hyperlink\" data-image=\"\" data-image-mobile=\"\" data-image-all=\"\" data-image-all-mobile=\"\" data-icon-color=\"#333\" data-text-color=\"#333\" data-client-id=\"block-c5314950-35ed-4321-a2e7-a4dcf90f85be\"><ul class=\"first-level\"><li><em><a href=\"#top\">Back to top<\/a><\/em><\/li><li><em><a href=\"#cUTIadult\">cUTI in adult patients<\/a><\/em><\/li><li><em><a href=\"#cUTIpediatric\">cUTI in pediatric patients<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<div style=\"background-color:transparent;--desktop-spacer:24px;--tablet-spacer:24px;--mobile-spacer:24px;height:24px\" class=\"wp-block-vivid360-spacer vivid360-spacer-desktop vivid360-spacer-tablet vivid360-spacer-mobile\"><\/div>\n","protected":false},"excerpt":{"rendered":"<p>A total of 1068 adults hospitalized with cUTI (including pyelonephritis) were randomized and received study medications in a multinational, double-blind study comparing&#8230;<\/p>\n","protected":false},"author":750,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_trash_the_other_posts":false,"editor_notices":[],"footnotes":""},"ga4_page_audience":[],"ga4_page_birn_id":[],"ga4_page_branding":[267],"ga4_page_businessunit":[],"ga4_page_campaign":[],"ga4_page_content_purpose":[294],"ga4_page_customer_journey_stage":[334],"ga4_page_customer_specialty":[358],"ga4_page_experience":[],"ga4_page_indication":[],"ga4_page_material_intent":[522],"ga4_page_product":[706],"ga4_page_region":[749],"ga4_page_therapeuticarea":[],"user_role":[],"mhh-area-of-interest":[],"access":[],"user_status":[],"class_list":["post-104","page","type-page","status-publish"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Clinical Efficacy Against Complicated Urinary Tract Infections (cUTI)<\/title>\n<meta name=\"description\" content=\"Review clinical data about complicated urinary tract infections (cUTI) in adult and pediatric patients.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Clinical Efficacy Against Complicated Urinary Tract Infections (cUTI)\" \/>\n<meta property=\"og:description\" content=\"Review clinical data about complicated urinary tract infections (cUTI) in adult and pediatric patients.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/\" \/>\n<meta property=\"og:site_name\" content=\"zerbaxa\" \/>\n<meta property=\"article:modified_time\" content=\"2026-04-09T12:13:25+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"5 minutes\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Clinical Efficacy Against Complicated Urinary Tract Infections (cUTI)","description":"Review clinical data about complicated urinary tract infections (cUTI) in adult and pediatric patients.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/","og_locale":"en_US","og_type":"article","og_title":"Clinical Efficacy Against Complicated Urinary Tract Infections (cUTI)","og_description":"Review clinical data about complicated urinary tract infections (cUTI) in adult and pediatric patients.","og_url":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/","og_site_name":"zerbaxa","article_modified_time":"2026-04-09T12:13:25+00:00","twitter_card":"summary_large_image","twitter_misc":{"Est. reading time":"5 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/","url":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/","name":"Clinical Efficacy Against Complicated Urinary Tract Infections (cUTI)","isPartOf":{"@id":"https:\/\/www.merckconnect.com\/zerbaxa\/#website"},"datePublished":"2023-08-29T13:14:44+00:00","dateModified":"2026-04-09T12:13:25+00:00","description":"Review clinical data about complicated urinary tract infections (cUTI) in adult and pediatric patients.","breadcrumb":{"@id":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.merckconnect.com\/zerbaxa\/clinical-efficacy-cuti\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.merckconnect.com\/zerbaxa\/"},{"@type":"ListItem","position":2,"name":"Clinical efficacy against cUTIs"}]},{"@type":"WebSite","@id":"https:\/\/www.merckconnect.com\/zerbaxa\/#website","url":"https:\/\/www.merckconnect.com\/zerbaxa\/","name":"zerbaxa","description":"Just another vip-msd.com site","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.merckconnect.com\/zerbaxa\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"}]}},"acf":[],"_links":{"self":[{"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/pages\/104","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/users\/750"}],"replies":[{"embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/comments?post=104"}],"version-history":[{"count":106,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/pages\/104\/revisions"}],"predecessor-version":[{"id":2602,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/pages\/104\/revisions\/2602"}],"wp:attachment":[{"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/media?parent=104"}],"wp:term":[{"taxonomy":"ga4_page_audience","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_audience?post=104"},{"taxonomy":"ga4_page_birn_id","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_birn_id?post=104"},{"taxonomy":"ga4_page_branding","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_branding?post=104"},{"taxonomy":"ga4_page_businessunit","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_businessunit?post=104"},{"taxonomy":"ga4_page_campaign","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_campaign?post=104"},{"taxonomy":"ga4_page_content_purpose","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_content_purpose?post=104"},{"taxonomy":"ga4_page_customer_journey_stage","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_customer_journey_stage?post=104"},{"taxonomy":"ga4_page_customer_specialty","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_customer_specialty?post=104"},{"taxonomy":"ga4_page_experience","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_experience?post=104"},{"taxonomy":"ga4_page_indication","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_indication?post=104"},{"taxonomy":"ga4_page_material_intent","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_material_intent?post=104"},{"taxonomy":"ga4_page_product","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_product?post=104"},{"taxonomy":"ga4_page_region","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_region?post=104"},{"taxonomy":"ga4_page_therapeuticarea","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/ga4_page_therapeuticarea?post=104"},{"taxonomy":"user_role","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/user_role?post=104"},{"taxonomy":"mhh-area-of-interest","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/mhh-area-of-interest?post=104"},{"taxonomy":"access","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/access?post=104"},{"taxonomy":"user_status","embeddable":true,"href":"https:\/\/www.merckconnect.com\/zerbaxa\/wp-json\/wp\/v2\/user_status?post=104"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}