Clinical efficacy of ZERBAXA\u00ae (ceftolozane and tazobactam) against HABP\/VABP<\/strong><\/h1><\/div>\n\n\n\n\n<\/div>\n\n\n\nTreatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP\/VABP)<\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nLearn about:<\/strong><\/h2><\/div>\n\n\n\n\n- Study design<\/a><\/em><\/li>
- Efficacy results<\/em><\/a><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Study design<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nZERBAXA was studied in critically ill patients.1<\/sup><\/p>\n\n\n\n<\/div>\n\n\n\n\n\n\n![\"In](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_Study_Treatment_Schematic_dk_dktp_6c0765.svg\")
![\"In](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_Study_Treatment_Schematic_dk_mbl_549075.svg\" "\\"\\"")
<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nPrimary efficacy endpoint:<\/strong> all-cause mortality at day 28. Objective was to demonstrate the noninferiority of ZERBAXA versus meropenem in adults with HABP\/VABP. For analysis of the overall treatment differences, 95% confidence intervals (Cls) were calculated as stratified Newcombe Cls.1<\/sup><\/p>\n\n\n\n<\/div>\n\n\n\n100% of patients in the trial were ventilated<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"\"](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/DET_Antibiotic_icon_dk_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n\nCurrent antibiotic failure<\/strong><\/h3><\/div>\n\n\n\nApproximately 13% of patients were failing current antibacterial therapy for HABP\/VABP<\/p>\n<\/div>\n<\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n![\"\"](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/DET_Risk_of_mortality_icon_dk_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n\nAPACHE II score<\/strong><\/strong><\/h3><\/div>\n\n\n\nPatients had a median baseline APACHE II score of 17, indicating a 24% mortality rate (1\/3 of patients had a score of \u226520, a 40% estimated mortality)1,2<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"\"](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/DET_Hospital_KO_icon_dk_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n\nHospitalized for \u22655 days<\/strong><\/h3><\/div>\n\n\n\n77% of patients had been hospitalized for \u22655 days, 92% in the ICU1<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\n- Back to top<\/a><\/em><\/li>
- Study design<\/a><\/em><\/li>
- Efficacy results<\/a><\/em><\/em><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Primary endpoint<\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\nZERBAXA achieved primary endpoint of noninferiority in day 28 all-cause mortality vs meropenem in adult patients with HABP\/VABP in ITT population.1<\/sup><\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"ASPECT-NP](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_Day_28_Chart_Horiz_dk_dktp_c208b7.svg\")
![\"ASPECT-NP](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_Day_28_Chart_Horiz_dk_mbl_30c3c8.svg\" "\\"\\"")
<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nThe analysis population for the primary endpoint was the ITT population, which included all randomized patients.<\/em>1<\/sup><\/p>\n\n\n\n- In the vHABP subgroup of patients (~28.5%), there was a favorable response for ZERBAXA in day 28 all-cause mortality.
- ZERBAXA 24.2% (24\/99) meropenem 37.0% (40\/108)<\/li><\/ul><\/li>
- In the VABP subgroup, day 28 all-cause mortality was 24.0% (63\/263) for ZERBAXA and 20.3% (52\/256) for meropenem<\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n
Kaplan-Meier for day 28 all-cause mortality including overall ITT population and subgroup analyses.<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nThe Kaplan-Meier plots were not powered to demonstrate statistical significance in subgroups and individual time points. Subgroup analyses were not powered for noninferiority testing.<\/strong>1,3,4,5<\/strong><\/sup><\/p>\n\n\n\n<\/div>\n\n\n\nKaplan-Meier plots of day 28 all-cause mortality<\/strong> overall ITT population<\/strong>1,3<\/strong><\/sup><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"Kaplan-Meier](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_ZER_KapMeier_Primary_chart_dk_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nvHABP subgroup4<\/sup><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"Kaplan-Meier](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_ZER_KapMeier_vHABPsub_chart_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nVABP subgroup1,3<\/sup><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"Kaplan-Meier](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2025\/10\/CAT_ZER_KapMeier_VABPsub_chart_dk_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nSubgroup of participants who failed prior antibiotic therapy in ASPECT-NP5,a<\/sup><\/span><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n![\"Kaplan-Meier](\"https:\/\/www.merckconnect.com\/zerbaxa\/wp-content\/uploads\/sites\/130\/2026\/03\/CAT_ZER_KapMeier_Failed_chart_dk_RGB.svg\")
<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\na<\/sup>Unstratified Newcombe CIs; positive differences are in favor of ceftolozane\/tazobactam; negative differences are in favor of meropenem.<\/p>\n\n\n\n<\/div>\n\n\n\nAdditional information and limitations for failed prior antibiotic therapy subgroup5<\/sup>: <\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n- Participants who were failing prior antibacterial therapy were a prospectively defined subgroup.<\/li>
- Antibacterial therapy received 72 h prior to starting study treatment in participants who were failing antibacterial treatment before included: beta-lactam\/BLI, fluoroquinolones, cephalosporins, aminoglycosides, macrolides, and carbapenems.<\/li>
- Participants with missing\/indeterminate data were reported as deceased.<\/li><\/ul><\/div>\n\n\n\n
Outcomes in participants with failure of initial antibacterial therapy for hospital\u2011acquired\/ventilator\u2011associated bacterial pneumonia prior to enrollment in the randomized, controlled phase 3 ASPECT\u2011NP trial of ceftolozane\/tazobactam versus meropenem by Kollef et al. Critical Care<\/em> (2022) 26:373 at https:\/\/doi.org\/10.1186\/s13054-022-04192-w, is licensed under Creative Commons 4.0 at http:\/\/creativecommons.org\/licenses\/by\/4.0\/<\/p>\n\n\n\n<\/div>\n\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n- Overall ITT population<\/mark><\/a><\/li>
- vHABP subgroup<\/mark><\/a><\/li>
- VABP subgroup<\/mark><\/a><\/li>
- Failed prior antibiotic subgroup<\/mark><\/a><\/li>
- References<\/mark><\/a> <\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\nReferences<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n1. Kollef MH, Nov\u00e1\u010dek M, Kivistik \u00dc, et al. Lancet Infect Dis.<\/em> 2019;19(12):1299-1311.<\/p>\n\n\n\n<\/div>\n\n\n\n2. APACHE II Calculator. Updated November 10, 2018. Accessed February 1, 2026. https:\/\/clincalc.com\/lcuMortality\/ APACHEll.aspx<\/p>\n\n\n\n
<\/div>\n\n\n\n3. Data available on request from the Merck National Service Center via email at daprequests@merck.com. Please specify information package US-ZER-01413<\/span>.<\/p>\n\n\n\n<\/div>\n\n\n\n4. Timsit JF, Huntington JA, Wunderink RG, et al. Crit Care<\/em>. 2021;25:290.<\/p>\n\n\n\n
Treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP\/VABP)<\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nLearn about:<\/strong><\/h2><\/div>\n\n\n\n\n- Study design<\/a><\/em><\/li>
- Efficacy results<\/em><\/a><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Study design<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nZERBAXA was studied in critically ill patients.1<\/sup><\/p>\n\n\n\n<\/div>\n\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nPrimary efficacy endpoint:<\/strong> all-cause mortality at day 28. Objective was to demonstrate the noninferiority of ZERBAXA versus meropenem in adults with HABP\/VABP. For analysis of the overall treatment differences, 95% confidence intervals (Cls) were calculated as stratified Newcombe Cls.1<\/sup><\/p>\n\n\n\n<\/div>\n\n\n\n100% of patients in the trial were ventilated<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nCurrent antibiotic failure<\/strong><\/h3><\/div>\n\n\n\nApproximately 13% of patients were failing current antibacterial therapy for HABP\/VABP<\/p>\n<\/div>\n<\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nAPACHE II score<\/strong><\/strong><\/h3><\/div>\n\n\n\nPatients had a median baseline APACHE II score of 17, indicating a 24% mortality rate (1\/3 of patients had a score of \u226520, a 40% estimated mortality)1,2<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nHospitalized for \u22655 days<\/strong><\/h3><\/div>\n\n\n\n77% of patients had been hospitalized for \u22655 days, 92% in the ICU1<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\n- Back to top<\/a><\/em><\/li>
- Study design<\/a><\/em><\/li>
- Efficacy results<\/a><\/em><\/em><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Primary endpoint<\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\nZERBAXA achieved primary endpoint of noninferiority in day 28 all-cause mortality vs meropenem in adult patients with HABP\/VABP in ITT population.1<\/sup><\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nThe analysis population for the primary endpoint was the ITT population, which included all randomized patients.<\/em>1<\/sup><\/p>\n\n\n\n- In the vHABP subgroup of patients (~28.5%), there was a favorable response for ZERBAXA in day 28 all-cause mortality.
- ZERBAXA 24.2% (24\/99) meropenem 37.0% (40\/108)<\/li><\/ul><\/li>
- In the VABP subgroup, day 28 all-cause mortality was 24.0% (63\/263) for ZERBAXA and 20.3% (52\/256) for meropenem<\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n
Kaplan-Meier for day 28 all-cause mortality including overall ITT population and subgroup analyses.<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nThe Kaplan-Meier plots were not powered to demonstrate statistical significance in subgroups and individual time points. Subgroup analyses were not powered for noninferiority testing.<\/strong>1,3,4,5<\/strong><\/sup><\/p>\n\n\n\n<\/div>\n\n\n\nKaplan-Meier plots of day 28 all-cause mortality<\/strong> overall ITT population<\/strong>1,3<\/strong><\/sup><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nvHABP subgroup4<\/sup><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nVABP subgroup1,3<\/sup><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nSubgroup of participants who failed prior antibiotic therapy in ASPECT-NP5,a<\/sup><\/span><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\na<\/sup>Unstratified Newcombe CIs; positive differences are in favor of ceftolozane\/tazobactam; negative differences are in favor of meropenem.<\/p>\n\n\n\n<\/div>\n\n\n\nAdditional information and limitations for failed prior antibiotic therapy subgroup5<\/sup>: <\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n- Participants who were failing prior antibacterial therapy were a prospectively defined subgroup.<\/li>
- Antibacterial therapy received 72 h prior to starting study treatment in participants who were failing antibacterial treatment before included: beta-lactam\/BLI, fluoroquinolones, cephalosporins, aminoglycosides, macrolides, and carbapenems.<\/li>
- Participants with missing\/indeterminate data were reported as deceased.<\/li><\/ul><\/div>\n\n\n\n
Outcomes in participants with failure of initial antibacterial therapy for hospital\u2011acquired\/ventilator\u2011associated bacterial pneumonia prior to enrollment in the randomized, controlled phase 3 ASPECT\u2011NP trial of ceftolozane\/tazobactam versus meropenem by Kollef et al. Critical Care<\/em> (2022) 26:373 at https:\/\/doi.org\/10.1186\/s13054-022-04192-w, is licensed under Creative Commons 4.0 at http:\/\/creativecommons.org\/licenses\/by\/4.0\/<\/p>\n\n\n\n<\/div>\n\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n- Overall ITT population<\/mark><\/a><\/li>
- vHABP subgroup<\/mark><\/a><\/li>
- VABP subgroup<\/mark><\/a><\/li>
- Failed prior antibiotic subgroup<\/mark><\/a><\/li>
- References<\/mark><\/a> <\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\nReferences<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n1. Kollef MH, Nov\u00e1\u010dek M, Kivistik \u00dc, et al. Lancet Infect Dis.<\/em> 2019;19(12):1299-1311.<\/p>\n\n\n\n<\/div>\n\n\n\n2. APACHE II Calculator. Updated November 10, 2018. Accessed February 1, 2026. https:\/\/clincalc.com\/lcuMortality\/ APACHEll.aspx<\/p>\n\n\n\n
<\/div>\n\n\n\n3. Data available on request from the Merck National Service Center via email at daprequests@merck.com. Please specify information package US-ZER-01413<\/span>.<\/p>\n\n\n\n<\/div>\n\n\n\n4. Timsit JF, Huntington JA, Wunderink RG, et al. Crit Care<\/em>. 2021;25:290.<\/p>\n\n\n\n
Learn about:<\/strong><\/h2><\/div>\n\n\n\n\n- Study design<\/a><\/em><\/li>
- Efficacy results<\/em><\/a><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Study design<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nZERBAXA was studied in critically ill patients.1<\/sup><\/p>\n\n\n\n<\/div>\n\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nPrimary efficacy endpoint:<\/strong> all-cause mortality at day 28. Objective was to demonstrate the noninferiority of ZERBAXA versus meropenem in adults with HABP\/VABP. For analysis of the overall treatment differences, 95% confidence intervals (Cls) were calculated as stratified Newcombe Cls.1<\/sup><\/p>\n\n\n\n<\/div>\n\n\n\n100% of patients in the trial were ventilated<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nCurrent antibiotic failure<\/strong><\/h3><\/div>\n\n\n\nApproximately 13% of patients were failing current antibacterial therapy for HABP\/VABP<\/p>\n<\/div>\n<\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nAPACHE II score<\/strong><\/strong><\/h3><\/div>\n\n\n\nPatients had a median baseline APACHE II score of 17, indicating a 24% mortality rate (1\/3 of patients had a score of \u226520, a 40% estimated mortality)1,2<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nHospitalized for \u22655 days<\/strong><\/h3><\/div>\n\n\n\n77% of patients had been hospitalized for \u22655 days, 92% in the ICU1<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\n- Back to top<\/a><\/em><\/li>
- Study design<\/a><\/em><\/li>
- Efficacy results<\/a><\/em><\/em><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Primary endpoint<\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\nZERBAXA achieved primary endpoint of noninferiority in day 28 all-cause mortality vs meropenem in adult patients with HABP\/VABP in ITT population.1<\/sup><\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nThe analysis population for the primary endpoint was the ITT population, which included all randomized patients.<\/em>1<\/sup><\/p>\n\n\n\n- In the vHABP subgroup of patients (~28.5%), there was a favorable response for ZERBAXA in day 28 all-cause mortality.
- ZERBAXA 24.2% (24\/99) meropenem 37.0% (40\/108)<\/li><\/ul><\/li>
- In the VABP subgroup, day 28 all-cause mortality was 24.0% (63\/263) for ZERBAXA and 20.3% (52\/256) for meropenem<\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n
Kaplan-Meier for day 28 all-cause mortality including overall ITT population and subgroup analyses.<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nThe Kaplan-Meier plots were not powered to demonstrate statistical significance in subgroups and individual time points. Subgroup analyses were not powered for noninferiority testing.<\/strong>1,3,4,5<\/strong><\/sup><\/p>\n\n\n\n<\/div>\n\n\n\nKaplan-Meier plots of day 28 all-cause mortality<\/strong> overall ITT population<\/strong>1,3<\/strong><\/sup><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nvHABP subgroup4<\/sup><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nVABP subgroup1,3<\/sup><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nSubgroup of participants who failed prior antibiotic therapy in ASPECT-NP5,a<\/sup><\/span><\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\na<\/sup>Unstratified Newcombe CIs; positive differences are in favor of ceftolozane\/tazobactam; negative differences are in favor of meropenem.<\/p>\n\n\n\n<\/div>\n\n\n\nAdditional information and limitations for failed prior antibiotic therapy subgroup5<\/sup>: <\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n- Participants who were failing prior antibacterial therapy were a prospectively defined subgroup.<\/li>
- Antibacterial therapy received 72 h prior to starting study treatment in participants who were failing antibacterial treatment before included: beta-lactam\/BLI, fluoroquinolones, cephalosporins, aminoglycosides, macrolides, and carbapenems.<\/li>
- Participants with missing\/indeterminate data were reported as deceased.<\/li><\/ul><\/div>\n\n\n\n
Outcomes in participants with failure of initial antibacterial therapy for hospital\u2011acquired\/ventilator\u2011associated bacterial pneumonia prior to enrollment in the randomized, controlled phase 3 ASPECT\u2011NP trial of ceftolozane\/tazobactam versus meropenem by Kollef et al. Critical Care<\/em> (2022) 26:373 at https:\/\/doi.org\/10.1186\/s13054-022-04192-w, is licensed under Creative Commons 4.0 at http:\/\/creativecommons.org\/licenses\/by\/4.0\/<\/p>\n\n\n\n<\/div>\n\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n- Overall ITT population<\/mark><\/a><\/li>
- vHABP subgroup<\/mark><\/a><\/li>
- VABP subgroup<\/mark><\/a><\/li>
- Failed prior antibiotic subgroup<\/mark><\/a><\/li>
- References<\/mark><\/a> <\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\nReferences<\/strong><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\n1. Kollef MH, Nov\u00e1\u010dek M, Kivistik \u00dc, et al. Lancet Infect Dis.<\/em> 2019;19(12):1299-1311.<\/p>\n\n\n\n<\/div>\n\n\n\n2. APACHE II Calculator. Updated November 10, 2018. Accessed February 1, 2026. https:\/\/clincalc.com\/lcuMortality\/ APACHEll.aspx<\/p>\n\n\n\n
<\/div>\n\n\n\n3. Data available on request from the Merck National Service Center via email at daprequests@merck.com. Please specify information package US-ZER-01413<\/span>.<\/p>\n\n\n\n<\/div>\n\n\n\n4. Timsit JF, Huntington JA, Wunderink RG, et al. Crit Care<\/em>. 2021;25:290.<\/p>\n\n\n\n
- Study design<\/a><\/em><\/li>
- Efficacy results<\/em><\/a><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n
<\/div>\n\n\n\nStudy design<\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\nZERBAXA was studied in critically ill patients.1<\/sup><\/p>\n\n\n\n
<\/div>\n\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nPrimary efficacy endpoint:<\/strong> all-cause mortality at day 28. Objective was to demonstrate the noninferiority of ZERBAXA versus meropenem in adults with HABP\/VABP. For analysis of the overall treatment differences, 95% confidence intervals (Cls) were calculated as stratified Newcombe Cls.1<\/sup><\/p>\n\n\n\n
<\/div>\n\n\n\n100% of patients in the trial were ventilated<\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nCurrent antibiotic failure<\/strong><\/h3><\/div>\n\n\n\n
Approximately 13% of patients were failing current antibacterial therapy for HABP\/VABP<\/p>\n<\/div>\n<\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nAPACHE II score<\/strong><\/strong><\/h3><\/div>\n\n\n\n
Patients had a median baseline APACHE II score of 17, indicating a 24% mortality rate (1\/3 of patients had a score of \u226520, a 40% estimated mortality)1,2<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n\nHospitalized for \u22655 days<\/strong><\/h3><\/div>\n\n\n\n
77% of patients had been hospitalized for \u22655 days, 92% in the ICU1<\/sup><\/p>\n<\/div>\n<\/div>\n\n\n\n
<\/div>\n\n\n\n- Back to top<\/a><\/em><\/li>
- Study design<\/a><\/em><\/li>
- Efficacy results<\/a><\/em><\/em><\/li>
- References<\/a><\/em><\/li><\/ul><\/div>\n\n\n\n
<\/div>\n\n\n\nPrimary endpoint<\/strong><\/h3><\/div>\n\n\n\n
<\/div>\n\n\n\nZERBAXA achieved primary endpoint of noninferiority in day 28 all-cause mortality vs meropenem in adult patients with HABP\/VABP in ITT population.1<\/sup><\/strong><\/h3><\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nThe analysis population for the primary endpoint was the ITT population, which included all randomized patients.<\/em>1<\/sup><\/p>\n\n\n\n
- In the vHABP subgroup of patients (~28.5%), there was a favorable response for ZERBAXA in day 28 all-cause mortality.
- ZERBAXA 24.2% (24\/99) meropenem 37.0% (40\/108)<\/li><\/ul><\/li>
- In the VABP subgroup, day 28 all-cause mortality was 24.0% (63\/263) for ZERBAXA and 20.3% (52\/256) for meropenem<\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n
Kaplan-Meier for day 28 all-cause mortality including overall ITT population and subgroup analyses.<\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\nThe Kaplan-Meier plots were not powered to demonstrate statistical significance in subgroups and individual time points. Subgroup analyses were not powered for noninferiority testing.<\/strong>1,3,4,5<\/strong><\/sup><\/p>\n\n\n\n
<\/div>\n\n\n\nKaplan-Meier plots of day 28 all-cause mortality<\/strong> overall ITT population<\/strong>1,3<\/strong><\/sup><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nvHABP subgroup4<\/sup><\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nVABP subgroup1,3<\/sup><\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\n<\/div>\n\n\n\nSubgroup of participants who failed prior antibiotic therapy in ASPECT-NP5,a<\/sup><\/span><\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\n\n\n<\/figure><\/div>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n\n\na<\/sup>Unstratified Newcombe CIs; positive differences are in favor of ceftolozane\/tazobactam; negative differences are in favor of meropenem.<\/p>\n\n\n\n
<\/div>\n\n\n\nAdditional information and limitations for failed prior antibiotic therapy subgroup5<\/sup>: <\/strong><\/h3><\/div>\n\n\n\n
<\/div>\n\n\n\n- Participants who were failing prior antibacterial therapy were a prospectively defined subgroup.<\/li>
- Antibacterial therapy received 72 h prior to starting study treatment in participants who were failing antibacterial treatment before included: beta-lactam\/BLI, fluoroquinolones, cephalosporins, aminoglycosides, macrolides, and carbapenems.<\/li>
- Participants with missing\/indeterminate data were reported as deceased.<\/li><\/ul><\/div>\n\n\n\n
Outcomes in participants with failure of initial antibacterial therapy for hospital\u2011acquired\/ventilator\u2011associated bacterial pneumonia prior to enrollment in the randomized, controlled phase 3 ASPECT\u2011NP trial of ceftolozane\/tazobactam versus meropenem by Kollef et al. Critical Care<\/em> (2022) 26:373 at https:\/\/doi.org\/10.1186\/s13054-022-04192-w, is licensed under Creative Commons 4.0 at http:\/\/creativecommons.org\/licenses\/by\/4.0\/<\/p>\n\n\n\n
<\/div>\n\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n- Overall ITT population<\/mark><\/a><\/li>
- vHABP subgroup<\/mark><\/a><\/li>
- VABP subgroup<\/mark><\/a><\/li>
- Failed prior antibiotic subgroup<\/mark><\/a><\/li>
- References<\/mark><\/a> <\/li><\/ul><\/div>\n\n\n\n
<\/div>\n\n\n\n
\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\n<\/div>\n\n\n\nReferences<\/strong><\/h2><\/div>\n\n\n\n
<\/div>\n\n\n\n1. Kollef MH, Nov\u00e1\u010dek M, Kivistik \u00dc, et al. Lancet Infect Dis.<\/em> 2019;19(12):1299-1311.<\/p>\n\n\n\n
<\/div>\n\n\n\n2. APACHE II Calculator. Updated November 10, 2018. Accessed February 1, 2026. https:\/\/clincalc.com\/lcuMortality\/ APACHEll.aspx<\/p>\n\n\n\n
<\/div>\n\n\n\n3. Data available on request from the Merck National Service Center via email at daprequests@merck.com. Please specify information package US-ZER-01413<\/span>.<\/p>\n\n\n\n
<\/div>\n\n\n\n4. Timsit JF, Huntington JA, Wunderink RG, et al. Crit Care<\/em>. 2021;25:290.<\/p>\n\n\n\n
- vHABP subgroup<\/mark><\/a><\/li>
- Overall ITT population<\/mark><\/a><\/li>
- Study design<\/a><\/em><\/li>
- Efficacy results<\/em><\/a><\/li>