A Study of Plazomicin Compared With Colistin in Patients With Infection Due to Carbapenem-Resistant Enterobacteriaceae (CRE)

ACM at Day 28: confirmed date of death within 28 days of the first dose of study drug, irrespective of causality. SDRCs for all patients: presence of 1 or more of the following complications within 7 days of randomization: new or worsening acute respiratory distress syndrome (ARDS), new lung abscess, new empyema, new onset of septic shock, new carbapenem-resistant Enterobacteriaceae (CRE) (HABP/VABP patients only); persistent bacteremia on study Day ≥5 (BSI patients only). Note: Although it is generally expected that results for primary and secondary endpoints will be presented for all arms included at baseline, results for Cohort 2 are not presented here as this Cohort was not part of the primary or key secondary endpoints per the protocol and statistical analysis plan (SAP).

Time frame: Up to Day 28 for ACM, up to 7 Days for SDRCs in all patients, on or after Day 5 for BSI patients only.

Population: The mMITT population was a subset of the MITT population and included all patients who received ≥1 dose of study drug and had a CRE pathogen. CRE=meropenem minimum inhibitory concentration (MIC) of ≥4 micrograms per milliliter (μg/mL) or meropenem MIC=2 μg/mL and disk diffusion results (≤19 millimetres \[mm\]) indicating meropenem resistance.

ACM at Day 14 was defined as a confirmed date of death within 14 days of the first dose of study drug, irrespective of causality. Note: Although it is generally expected that results for primary and secondary endpoints will be presented for all arms included at baseline, results for Cohort 2 are not presented here as this Cohort was not part of the primary or key secondary endpoints per the protocol and SAP.

Time frame: Day 14

Population: The mMITT population was a subset of MITT population and included all patients who received ≥1 dose of study drug and had a CRE pathogen. CRE=meropenem MIC of ≥4 μg/mL or meropenem MIC=2 μg/mL and disk diffusion results (≤19 mm) indicating meropenem resistance.

ACM at Day 28: confirmed date of death within 28 days of the first dose of study drug, irrespective of causality. Note: Although it is generally expected that results for primary and secondary endpoints will be presented for all arms included at baseline, results for Cohort 2 are not presented here as this Cohort was not part of the primary or key secondary endpoints per the protocol and SAP.

Time frame: Up to Day 28

Population: The mMITT population was a subset of MITT population and included all patients who received at least 1 dose of study drug and had a CRE pathogen. CRE=meropenem MIC of ≥4 μg/mL or meropenem MIC=2 μg/mL and disk diffusion results (≤19 mm) indicating meropenem resistance.

Clinical response (CR) was assessed at end of treatment (EOT) in all patients and at TOC for those who were a clinical cure or had an indeterminate outcome at the most recent visit. Assessment of CR at TOC was not needed for those who were a clinical failure at an earlier visit. Clinical outcomes at both EOT and TOC were independently adjudicated by an external committee. The assessment was confounded by comorbidities and the occurrence of additional infections; thus, adjudicating CR of the baseline CRE infection was influenced by confounding signs and symptoms of unrelated infections or conditions. The difficulty assessing CR supports greater reliance on the more objective mortality-based primary endpoint in these patients. Note: Although it is generally expected that results for primary and secondary endpoints will be presented for all arms included at baseline, results for Cohort 2 are not presented here as this Cohort was not part of the endpoints per the protocol and SAP.

Time frame: Up to TOC (Day 23)

Population: The mMITT population was a subset of MITT population and included all patients who received at least 1 dose of study drug and had a CRE pathogen. CRE=meropenem MIC of ≥4 μg/mL or meropenem MIC=2 μ/mL and disk diffusion results (≤19 mm) indicating meropenem resistance.

After the initial plazomicin dose, subsequent doses were adjusted, as directed, with the use of TDM on Day 1, 4, and 8 as needed. Note: Although it is generally expected that results for primary and secondary endpoints will be presented for all arms included at baseline, results for Cohort 1: Colistin are not presented here as TDM collection does not apply to and was not collected for patients in the colistin arm, as only plazomicin levels were measured.

Time frame: Up to Day 14

Population: The safety population included all randomized patients who received any amount of study drug.

An adverse event (AE) is any untoward medical occurrence associated with the use of a drug in humans, whether or not it is considered to be drug related. An AE (also referred to as an adverse experience) can be any unfavorable and unintended sign (eg, an abnormal laboratory finding), symptom, or disease temporally associated with the use of a drug, and it does not imply any judgment about causality. Adverse events also include the exacerbation or worsening of a condition present at screening other than the index infection for which the patient was enrolled in the study. A TEAE is any AE that newly appeared, increased in frequency, or worsened in severity following initiation of study drug. The safety population included all randomized patients who received any amount of study drug.

Time frame: Up to Day 67

Population: The safety population included all randomized patients who received any amount of study drug.

PK specimens were collected on Days 1 and 4 using a sparse sampling scheme, and concentration-time data from these PK specimens were pooled with data from specimens collected for TDM. The pooled data were analyzed by population PK modeling, which described PK over the entire course of plazomicin treatment. The protocol allowed dose adjustments based on creatinine clearance; therefore, various dose regimens were used in the study, including regimens with dosing intervals of 12, 24, and 48 hours. To enable a combined summation of exposures across dose regimens, PK exposure parameters for the study were summarized for the first 48 hours of treatment. Thus, while exposures are summarized for the first 48 hours, the reported results considered patient data over the course of plazomicin treatment.

Time frame: 48 hours

Population: PK population included all patients who had received at least 1 dose of plazomicin and had at least 1 quantifiable plazomicin plasma concentration available for analysis.

PK specimens were collected on Days 1 and 4 using a sparse sampling scheme, and concentration-time data from these PK specimens were pooled with data from specimens collected for TDM. The pooled data were analyzed by population PK modeling, which described PK over the entire course of plazomicin treatment. The protocol allowed dose adjustments based on creatinine clearance; therefore, various dose regimens were used in the study, including regimens with dosing intervals of 12, 24, and 48 hours. To enable a combined summation of exposures across dose regimens, PK exposure parameters for the study were summarized for the first 48 hours of treatment. Thus, while exposures are summarized for the first 48 hours, the reported results considered patient data over the course of plazomicin treatment.

Time frame: 48 hours

Population: PK population included all patients who had received at least 1 dose of plazomicin and had at least 1 quantifiable plazomicin plasma concentration available for analysis.

PK specimens were collected on Days 1 and 4 using a sparse sampling scheme, and concentration-time data from these PK specimens were pooled with data from specimens collected for TDM. The pooled data were analyzed by population PK modeling, which described PK over the entire course of plazomicin treatment. The protocol allowed dose adjustments based on creatinine clearance; therefore, various dose regimens were used in the study, including regimens with dosing intervals of 12, 24, and 48 hours. To enable a combined summation of exposures across dose regimens, PK exposure parameters for the study were summarized for the first 48 hours of treatment. Thus, while exposures are summarized for the first 48 hours, the reported results considered patient data over the course of plazomicin treatment.

Time frame: 48 hours

Population: PK population included all patients who had received at least 1 dose of plazomicin and had at least 1 quantifiable plazomicin plasma concentration available for analysis.

Time to death through Day 28 is defined as days from first dose of study drug to death from any cause on or before Day 28. Patients who were alive at Day 28 were censored on Day 28. Any patient whose survival status was not known at Day 28 was censored on the last known date alive. Note: Although it is generally expected that results for primary and secondary endpoints will be presented for all arms included at baseline, results for Cohort 2 are not presented here as this Cohort was not part of the primary or key secondary endpoints per the protocol and SAP.

Time frame: Up to Day 28

Population: The mMITT population included all patients who received at least 1 dose of study drug and had a CRE pathogen. CRE=meropenem MIC of ≥4 μg/mL or meropenem MIC=2 μg/mL and disk diffusion results (≤19 mm) indicating meropenem resistance.