Trial Outcomes & Findings for Ceftolozane-Tazobactam for Directed Treatment of Pseudomonas Aeruginosa Bacteremia and Pneumonia in Patients With Hematological Malignancies and Hematopoietic Stem Cell Transplantation (NCT NCT04673175)

Last Updated: 2026-01-21

Results Overview

Clinical success 30 days after collection of the index culture. Clinical success is defined as meeting all of the following criteria at that time point: survival; resolution or near resolution of baseline clinical manifestations, including fever, hypoxia, and signs or symptoms of sepsis; and absence of recurrent infection due to Pseudomonas aeruginosa or persistent infection despite more than 7 days of anti-pseudomonal therapy.

Recruitment status

TERMINATED

Study phase

PHASE4

Target enrollment

17 participants

Primary outcome timeframe

30 days after collection of the index culture

Results posted on

2026-01-21

Participant Flow

Prospective participants for the ceftolozane-tazobactam arm were recruited at a single academic tertiary care hospital among adults with hematologic malignancies or hematopoietic stem cell transplant and documented Pseudomonas aeruginosa bacteremia or pneumonia between January 2023 and February 2025. Historical controls were identified retrospectively from the same institution.

A total of 17 consent events occurred among 16 unique participants. Per protocol, one participant was eligible for re-enrollment after developing a separate Pseudomonas aeruginosa infection and received study treatment during both enrollments. For statistical analyses, this participant was counted once to avoid bias. Analyses therefore summarize outcomes for 16 unique treated participants.

Participant milestones

Participant milestones
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Overall Study STARTED	16	48
Overall Study COMPLETED	16	48
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Ceftolozane-Tazobactam for Directed Treatment of Pseudomonas Aeruginosa Bacteremia and Pneumonia in Patients With Hematological Malignancies and Hematopoietic Stem Cell Transplantation

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.	Total n=64 Participants Total of all reporting groups
Age, Continuous	68.5 years n=37 Participants	66 years n=44 Participants	67 years n=40 Participants
Sex: Female, Male Female	1 Participants n=37 Participants	23 Participants n=44 Participants	24 Participants n=40 Participants
Sex: Female, Male Male	15 Participants n=37 Participants	25 Participants n=44 Participants	40 Participants n=40 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=37 Participants	5 Participants n=44 Participants	5 Participants n=40 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	15 Participants n=37 Participants	35 Participants n=44 Participants	50 Participants n=40 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	1 Participants n=37 Participants	8 Participants n=44 Participants	9 Participants n=40 Participants
Infection Type at Index Pseudomonas Infection Bacteremia	13 Participants n=37 Participants	39 Participants n=44 Participants	52 Participants n=40 Participants
Infection Type at Index Pseudomonas Infection Pneumonia	3 Participants n=37 Participants	9 Participants n=44 Participants	12 Participants n=40 Participants
Neutropenia Status at Index Pseudomonas Infection Neutropenic	7 Participants n=37 Participants	21 Participants n=44 Participants	28 Participants n=40 Participants
Neutropenia Status at Index Pseudomonas Infection Not Neutropenic	9 Participants n=37 Participants	27 Participants n=44 Participants	36 Participants n=40 Participants
Race/Ethnicity, Customized Race · American Indian or Alaska Native	0 Participants n=37 Participants	0 Participants n=44 Participants	0 Participants n=40 Participants
Race/Ethnicity, Customized Race · Asian	1 Participants n=37 Participants	3 Participants n=44 Participants	4 Participants n=40 Participants
Race/Ethnicity, Customized Race · Native Hawaiian or Other Pacific Islander	0 Participants n=37 Participants	0 Participants n=44 Participants	0 Participants n=40 Participants
Race/Ethnicity, Customized Race · Black or African American	1 Participants n=37 Participants	7 Participants n=44 Participants	8 Participants n=40 Participants
Race/Ethnicity, Customized Race · White	14 Participants n=37 Participants	27 Participants n=44 Participants	41 Participants n=40 Participants
Race/Ethnicity, Customized Race · Other combinations not described	0 Participants n=37 Participants	9 Participants n=44 Participants	9 Participants n=40 Participants
Race/Ethnicity, Customized Race · Decline to answer	0 Participants n=37 Participants	2 Participants n=44 Participants	2 Participants n=40 Participants
Hematologic Malignancy Type Acute myeloid leukemia	8 Participants n=37 Participants	18 Participants n=44 Participants	26 Participants n=40 Participants
Hematologic Malignancy Type Acute lymphoblastic leukemia	1 Participants n=37 Participants	4 Participants n=44 Participants	5 Participants n=40 Participants
Hematologic Malignancy Type Chronic leukemia	3 Participants n=37 Participants	3 Participants n=44 Participants	6 Participants n=40 Participants
Hematologic Malignancy Type Non-Hodgkin's lymphoma	3 Participants n=37 Participants	14 Participants n=44 Participants	17 Participants n=40 Participants
Hematologic Malignancy Type Multiple myeloma	1 Participants n=37 Participants	7 Participants n=44 Participants	8 Participants n=40 Participants
Hematologic Malignancy Type Myelodysplastic Syndromes	4 Participants n=37 Participants	5 Participants n=44 Participants	9 Participants n=40 Participants
Hematopoietic cell transplant recipient Yes	10 Participants n=37 Participants	18 Participants n=44 Participants	28 Participants n=40 Participants
Hematopoietic cell transplant recipient No	6 Participants n=37 Participants	30 Participants n=44 Participants	36 Participants n=40 Participants
Pitt Bacteremia Score	0.5 score on a scale n=37 Participants	1 score on a scale n=44 Participants	1 score on a scale n=40 Participants
Age-adjusted Charlson Comorbidity Index	6 score on a scale n=37 Participants	5 score on a scale n=44 Participants	5 score on a scale n=40 Participants

PRIMARY outcome

Timeframe: 30 days after collection of the index culture

Population: Outcome measures were summarized for 16 unique prospective participants and 48 historical controls, matching the numbers in Participant Flow. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection is counted once for this measure, consistent with the analysis datasets.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Clinical Success at Day 30 Clinical Failure	4 Participants	18 Participants
Clinical Success at Day 30 Clinical Success	12 Participants	30 Participants

SECONDARY outcome

Timeframe: 30 days after initiation of anti-pseudomonal therapy for the index infection

Survival status 30 days after initiation of anti-pseudomonal therapy for the index infection, assessed by chart review or phone contact.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Survival at Day 30 Alive	15 Participants	35 Participants
Survival at Day 30 Deceased	1 Participants	13 Participants

SECONDARY outcome

Timeframe: 60 days after initiation of anti-pseudomonal therapy for the index infection

Survival status 60 days after initiation of anti-pseudomonal therapy for the index infection, assessed by chart review or phone contact.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Survival at Day 60 Alive	13 Participants	28 Participants
Survival at Day 60 Deceased	3 Participants	20 Participants

SECONDARY outcome

Timeframe: From index culture collection up to 60 days

Population: Analysis limited to participants with Pseudomonas aeruginosa bacteremia who had follow-up blood cultures after the index culture. Participants without follow-up blood cultures were excluded from this outcome. One participant in the prospective cohort was re-enrolled for a second Pseudomonas aeruginosa infection and is counted once for this measure, consistent with the analysis datasets.

Time (days) from the index positive blood culture for Pseudomonas aeruginosa to bacteremia resolution. Resolution was defined as the date of the first of two consecutive negative blood cultures obtained after the index culture. Participants without follow-up blood cultures were excluded from this analysis.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=13 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=38 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Time to Resolution of Bacteremia	2 Days Interval 1.0 to 2.0	1 Days Interval 1.0 to 2.0

SECONDARY outcome

Timeframe: From index culture collection through discharge from the hospital admission for the index infection (up to 60 days)

Total number of days hospitalized for the admission during which the index Pseudomonas aeruginosa infection is treated, measured beginning on the date of index culture collection and obtained from the Hospitalization Status Assessment.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Length of Hospital Stay	17.5 Days Interval 12.0 to 38.0	17 Days Interval 12.5 to 25.5

SECONDARY outcome

Timeframe: From index culture collection up to 60 days

Population: Assessed only among participants who received ceftolozane-tazobactam. Historical controls were not analyzed (0 participants) because they did not receive ceftolozane-tazobactam. One participant in the prospective cohort was re-enrolled for a second Pseudomonas aeruginosa infection and is counted once for this measure, consistent with the analysis datasets.

Occurrence of Pseudomonas aeruginosa isolates that newly demonstrate resistance to ceftolozane-tazobactam on antimicrobial susceptibility testing after initiation of therapy for the index infection.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Emergence of Ceftolozane-tazobactam Resistant Isolates Emergence of ceftolozane-tazobactam resistant isolate	0 Participants	—
Emergence of Ceftolozane-tazobactam Resistant Isolates No emergence of ceftolozane-tazobactam resistant isolate	16 Participants	—

SECONDARY outcome

Timeframe: From index culture collection up to 60 days

Time (in hours) from index culture collection for the index Pseudomonas aeruginosa infection to initiation of an anti-pseudomonal agent deemed appropriate based on antimicrobial susceptibility results.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Time to Appropriate Therapy	1 Hours Interval 0.0 to 5.5	3 Hours Interval 0.0 to 22.0

SECONDARY outcome

Timeframe: 30 days after collection of the index culture

Resolution or near resolution of baseline fever, hypoxia, or signs and symptoms of sepsis related to the index infection at 30 days after index culture collection, as assessed by physical examination findings and clinical documentation.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Resolution of Baseline Clinical Manifestations Resolution or near resolution achieved	14 Participants	33 Participants
Resolution of Baseline Clinical Manifestations Resolution or near resolution not achieved	2 Participants	15 Participants

SECONDARY outcome

Timeframe: From initiation of study ceftolozane-tazobactam therapy through end of study-directed anti-pseudomonal treatment (up to 21 days)

Population: Assessed only among participants who received study-directed ceftolozane-tazobactam. Historical controls were not analyzed (0 participants) because they did not receive ceftolozane-tazobactam. One participant in the prospective cohort was re-enrolled for a second Pseudomonas aeruginosa infection and is counted once for this measure, consistent with the analysis datasets.

Number of participants with any modification to the initial study-directed anti-pseudomonal regimen for the index infection, defined as either (1) discontinuation of ceftolozane-tazobactam with switch to another anti-pseudomonal agent or (2) addition of another anti-pseudomonal antibiotic during the treatment course. Outpatient levofloxacin was not considered a modification.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Modifications to Initial Antimicrobial Therapy Modification to initial regimen	3 Participants	—
Modifications to Initial Antimicrobial Therapy No modification to initial regimen	13 Participants	—

SECONDARY outcome

Timeframe: From initiation of study ceftolozane-tazobactam therapy through end of ceftolozane-tazobactam treatment (up to 21 days)

Identification of new bacterial pathogens identified in blood cultures during study-directed ceftolozane-tazobactam treatment for the index infection.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Emergence of Other Bacteria During Therapy New bacterial pathogen identified	0 Participants	—
Emergence of Other Bacteria During Therapy No new bacterial pathogen identified	16 Participants	—

SECONDARY outcome

Timeframe: From index culture collection through discharge from the hospital admission for the index infection (up to 60 days)

Total number of days requiring invasive mechanical ventilation during the index admission, measured beginning on the date of index culture collection and abstracted from the medical record.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Number of Days on Ventilator	0 Days Interval 0.0 to 0.0	0 Days Interval 0.0 to 0.0

SECONDARY outcome

Timeframe: From index culture collection through discharge from the hospital admission for the index infection (up to 60 days)

Total number of days spent in an intensive care unit during the index admission, measured beginning on the date of index culture collection and obtained from the Hospitalization Status Assessment.

Outcome measures

Outcome measures
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 Participants Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) n=48 Participants This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
ICU Length of Stay	0 Days Interval 0.0 to 1.0	0 Days Interval 0.0 to 2.5

Adverse Events

Ceftolozane-Tazobactam (Prospective Treatment Arm)

Serious events: 5 serious events

Other events: 0 other events

Deaths: 3 deaths

Historical Control (Standard of Care Prior to Study)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 20 deaths

Serious adverse events

Serious adverse events
Measure	Ceftolozane-Tazobactam (Prospective Treatment Arm) n=16 participants at risk Participants prospectively enrolled in the study received ceftolozane-tazobactam intravenously every 8 hours for approximately 10 to 14 days, with treatment extended up to 21 days if infection persisted or recurred. Outcomes for this arm were assessed according to the protocol's primary and secondary endpoints.	Historical Control (Standard of Care Prior to Study) This arm consists of historical control patients with documented Pseudomonas aeruginosa bacteremia and/or pneumonia who received standard-of-care antimicrobial therapy prior to initiation of this study. These patients were included retrospectively for comparative analyses of selected primary and secondary endpoints. No study interventions were administered to this arm.
Respiratory, thoracic and mediastinal disorders Suspected Aspiration	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
Immune system disorders Graft-versus-host disease exacerbation	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
Infections and infestations Pseudomonas aeruginosa bacteremia	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
Respiratory, thoracic and mediastinal disorders Acute Respiratory Failure	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
Blood and lymphatic system disorders Febrile neutropenia	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
Respiratory, thoracic and mediastinal disorders Respiratory failure	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
Infections and infestations Cytomegalovirus viremia	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.
General disorders Death	6.2% 1/16 • Number of events 1 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.	— 0/0 • From index culture collection through 60 days after initiation of anti-pseudomonal therapy (up to 60 days) SAEs were collected prospectively for participants receiving ceftolozane-tazobactam and classified per CTCAE v5.0. Only SAEs and deaths were systematically assessed; non-serious AEs were not collected. The participant who was re-enrolled for a second Pseudomonas aeruginosa infection episode is counted once for adverse event reporting purposes, consistent with the analysis datasets. AEs and SAEs for historical controls were not systematically collected, except for all-cause mortality.

Other adverse events

Adverse event data not reported

Additional Information

Markus Plate, MD

Weill Cornell Medicine

Phone: 212-746-7587

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place