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Visual Abstract.Trial of Cefepime vs Piperacillin-Tazobactam in Adults Hospitalized With Acute Infection
Figure 1. Flow of Participants Through the ACORN Trial

ACORN indicates Antibiotic Choice on Renal Outcomes.

aA tool in the electronic health record screened all patients presenting to the study hospital for the presence of inclusion criteria (≥18 years of age; being treated in participating emergency department or intensive care unit; <12 hours since presentation to the hospital; and order initiated for antipseudomonal cephalosporin or penicillin).

bIncluded clinician preference, metronidazole shortage, and no reason recorded.

Figure 2. Receipt of Antibiotics by Group

Patients may have received both cefepime and piperacillin-tazobactam on a study day when switching from one antibiotic to the other; 32 patients (1.3%) received both antibiotics on more than 1 consecutive study day.

Figure 3. Effect Modification of the Primary and Secondary Outcomes

The results of tests for interaction appear in eTables 14, 21, and 22 in Supplement 2.

aThe primary outcome was the highest stage or death by day 14 (score range, 0 [alive without acute kidney injury] to 4 [dead]). An odds ratio (OR) <1.0 indicates a better outcome with cefepime.

bDefined as a composite of death, receipt of new kidney replacement therapy, or final creatinine level that was at least 2 times the baseline level. An OR <1.0 indicates a better outcome with cefepime.

cThe number of days from randomization to day 14. An OR >1.0 indicates a better outcome with cefepime.

dClinician uncertain about the suspected source of infection at enrollment.

ePresence or absence at enrollment.

Table 1. Patient Characteristics at Baseline
Table 2. Primary, Secondary, and Exploratory Outcomes
1.
Evans L, Rhodes A, Alhazzani W, et al. Surviving sepsis campaign: international guidelines for management of sepsis and septic shock 2021. Intensive Care Med. 2021;47(11):1181-1247. doi:
2.
Abanades S, Nolla J, Rodríguez-Campello A, Pedro C, Valls A, Farré M. Reversible coma secondary to cefepime neurotoxicity. Ann Pharmacother. 2004;38(4):606-608. doi:
3.
Balderia PG, Chandorkar A, Kim Y, Patnaik S, Sloan J, Newman GC. Dosing cefepime for renal function does not completely prevent neurotoxicity in a patient with kidney transplant. J Patient Saf. 2018;14(2):e33-e34. doi:
4.
Drago L, De Vecchi E. The safety of cefepime in the treatment of infection. Expert Opin Drug Saf. 2008;7(4):377-387. doi:
5.
Appa AA, Jain R, Rakita RM, Hakimian S, Pottinger PS. Characterizing cefepime neurotoxicity: a systematic review. Open Forum Infect Dis. 2017;4(4):ofx170. doi:
6.
Bellos I, Karageorgiou V, Pergialiotis V, Perrea DN. Acute kidney injury following the concurrent administration of antipseudomonal β-lactams and vancomycin: a network meta-analysis. Clin Microbiol Infect. 2020;26(6):696-705. doi:
7.
Blevins AM, Lashinsky JN, McCammon C, Kollef M, Micek S, Juang P. Incidence of acute kidney injury in critically ill patients receiving vancomycin with concomitant piperacillin-tazobactam, cefepime, or meropenem. Antimicrob Agents Chemother. 2019;63(5):e02658-18. doi:
8.
O’Callaghan K, Hay K, Lavana J, McNamara JF. Acute kidney injury with combination vancomycin and piperacillin-tazobactam therapy in the ICU: a retrospective cohort study. Int J Antimicrob Agents. 2020;56(1):106010. doi:
9.
Tong SYC, Lye DC, Yahav D, et al; Australasian Society for Infectious Diseases Clinical Research Network. Effect of vancomycin or daptomycin with vs without an antistaphylococcal β-lactam on mortality, bacteremia, relapse, or treatment failure in patients with MRSA bacteremia: a randomized clinical trial. Ѵ. 2020;323(6):527-537. doi:
10.
Qian ET, Casey JD, Wright A, et al; Vanderbilt Learning Healthcare System Platform Investigators. Protocol and statistical analysis plan for the Antibiotic Choice On ReNal outcomes (ACORN) randomised clinical trial. Ѵ Open. 2023;13(3):e066995. doi:
11.
Seymour CW, Liu VX, Iwashyna TJ, et al. Assessment of clinical criteria for sepsis: for the third international consensus definitions for sepsis and septic shock (Sepsis-3). Ѵ. 2016;315(8):762-774. doi:
12.
Ely EW, Inouye SK, Bernard GR, et al. Delirium in mechanically ventilated patients: validity and reliability of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Ѵ. 2001;286(21):2703-2710. doi:
13.
Sessler CN, Gosnell MS, Grap MJ, et al. The Richmond Agitation-Sedation Scale: validity and reliability in adult intensive care unit patients. Am J Respir Crit Care Med. 2002;166(10):1338-1344. doi:
14.
Teasdale G, Jennett B. Assessment of coma and impaired consciousness: a practical scale. Գ. 1974;2(7872):81-84. doi:
15.
Singer M, Deutschman CS, Seymour CW, et al. The third international consensus definitions for sepsis and septic shock (Sepsis-3). Ѵ. 2016;315(8):801-810. doi:
16.
Leligdowicz A, Dodek PM, Norena M, Wong H, Kumar A, Kumar A; Co-operative Antimicrobial Therapy of Septic Shock Database Research Group. Association between source of infection and hospital mortality in patients who have septic shock. Am J Respir Crit Care Med. 2014;189(10):1204-1213. doi:
17.
Kidney Disease Improving Global Outcomes (KDIGO) Acute Kidney Injury Work Group. KDIGO clinical practice guideline for acute kidney injury. Kidney Int Suppl. 2012;2(1):1-138. doi:
18.
Semler MW, Rice TW, Shaw AD, et al. Identification of major adverse kidney events within the electronic health record. J Med Syst. 2016;40(7):167. doi:
19.
Semler MW, Self WH, Wanderer JP, et al; SMART Investigators and the Pragmatic Critical Care Research Group. Balanced crystalloids versus saline in critically ill adults. N Engl J Med. 2018;378(9):829-839. doi:
20.
Colantuoni E, Scharfstein DO, Wang C, et al. Statistical methods to compare functional outcomes in randomized controlled trials with high mortality. Ѵ. 2018;360:j5748. doi:
21.
Palevsky PM, Molitoris BA, Okusa MD, et al. Design of clinical trials in acute kidney injury: report from an NIDDK workshop on trial methodology. Clin J Am Soc Nephrol. 2012;7(5):844-850. doi:
22.
Andersen-Ranberg NC, Poulsen LM, Perner A, et al; AID-ICU Trial Group. Haloperidol for the treatment of delirium in ICU patients. N Engl J Med. 2022;387(26):2425-2435. doi:
23.
Girard TD, Exline MC, Carson SS, et al; MIND-USA Investigators. Haloperidol and ziprasidone for treatment of delirium in critical illness. N Engl J Med. 2018;379(26):2506-2516. doi:
24.
Qian ET, Wang L, Stollings JL, Casey JD, Rice TW, Semler MW. Piperacillin-tazobactam versus anti-pseudomonal cephalosporins and renal and neurologic outcomes in critically ill adults: a secondary analysis of the SMART Trial. J Intensive Care Med. Published online June 26, 2023. doi:
25.
Schandelmaier S, Briel M, Varadhan R, et al. Development of the Instrument to assess the Credibility of Effect Modification Analyses (ICEMAN) in randomized controlled trials and meta-analyses. Ѵ. 2020;192(32):E901-E906. doi:
26.
Peto R, Pike MC, Armitage P, et al. Design and analysis of randomized clinical trials requiring prolonged observation of each patient, I: introduction and design. Br J Cancer. 1976;34(6):585-612. doi:
27.
Wen S, Wang C, Duan Y, et al. OAT1 and OAT3 also mediate the drug-drug interaction between piperacillin and tazobactam. Int J Pharm. 2018;537(1-2):172-182. doi:
28.
Miano TA, Hennessy S, Yang W, et al. Association of vancomycin plus piperacillin-tazobactam with early changes in creatinine versus cystatin C in critically ill adults: a prospective cohort study. Intensive Care Med. 2022;48(9):1144-1155. doi:
29.
Chang J, Pais GM, Valdez K, Marianski S, Barreto EF, Scheetz MH. Glomerular function and urinary biomarker changes between vancomycin and vancomycin plus piperacillin-tazobactam in a translational rat model. Antimicrob Agents Chemother. 2022;66(3):e0213221. doi:
30.
Pais GM, Liu J, Avedissian SN, et al. Lack of synergistic nephrotoxicity between vancomycin and piperacillin/tazobactam in a rat model and a confirmatory cellular model. J Antimicrob Chemother. 2020;75(5):1228-1236. doi:
31.
Pfizer Injectables. ZOSYN (piperacillin and tazobactam) for injection. Published May 2017. Accessed June 7, 2023.
32.
Durand-Maugard C, Lemaire-Hurtel AS, Gras-Champel V, et al. Blood and CSF monitoring of cefepime-induced neurotoxicity: nine case reports. J Antimicrob Chemother. 2012;67(5):1297-1299. doi:
33.
Sugimoto M, Uchida I, Mashimo T, et al. Evidence for the involvement of GABA(A) receptor blockade in convulsions induced by cephalosporins. ܰDZ󲹰DZDz. 2003;45(3):304-314. doi:
34.
Payne LE, Gagnon DJ, Riker RR, et al. Cefepime-induced neurotoxicity: a systematic review. Crit Care. 2017;21(1):276. doi:
35.
Boschung-Pasquier L, Atkinson A, Kastner LK, et al. Cefepime neurotoxicity: thresholds and risk factors: a retrospective cohort study. Clin Microbiol Infect. 2020;26(3):333-339. doi:
36.
Lee SJ. Cefepime-induced neurotoxicity. J Neurocritical Care. 2019;12(2):74-84. doi:
37.
Mani N, Murray J, Gulick RM, et al. Novel clinical trial designs for the development of new antiretroviral agents. ٳ. 2012;26(8):899-907. doi:
38.
US Department of Health and Human Services. Multiple endpoints in clinical trials guidance for industry. Published January 2017. Accessed June 7, 2023.
Views 120,961
Original Investigation
Caring for the Critically Ill Patient
October 14, 2023

Cefepime vs Piperacillin-Tazobactam in Adults Hospitalized With Acute Infection: The ACORN Randomized Clinical Trial

Author Affiliations
  • 1Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
  • 2Department of Bioinformatics, Vanderbilt University Medical Center, Nashville, Tennessee
  • 3Division of General Internal Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
  • 4Department of Biostatistics, School of Medicine, Vanderbilt University, Nashville, Tennessee
  • 5Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, Tennessee
  • 6Department of Pharmaceutical Services, Vanderbilt University Medical Center, Nashville, Tennessee
  • 7Department of Emergency Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
  • 8Division of Infectious Diseases, Vanderbilt University Medical Center, Nashville, Tennessee
  • 9Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Nashville, Tennessee
  • 10Division of Acute Care Surgery, Vanderbilt University Medical Center, Nashville, Tennessee
  • 11Geriatric Research, Education, and Clinical Center, Tennessee Valley Healthcare System, Nashville
JAMA. 2023;330(16):1557-1567. doi:10.1001/jama.2023.20583
Visual Abstract.Trial of Cefepime vs Piperacillin-Tazobactam in Adults Hospitalized With Acute Infection
Key Points

Question Does the choice between cefepime and piperacillin-tazobactam affect the risks of acute kidney injury or neurological dysfunction in adults hospitalized with acute infection?

Findings Among 2511 adults hospitalized with acute infection, the highest stage of acute kidney injury or death was not significantly different between patients randomized to cefepime and those randomized to piperacillin-tazobactam. Patients randomized to cefepime experienced more neurological dysfunction, a secondary outcome.

Meaning Among hospitalized adults, the risk of acute kidney injury did not differ between cefepime and piperacillin-tazobactam, but neurological dysfunction was more common with cefepime.

Abstract

Importance Cefepime and piperacillin-tazobactam are commonly administered to hospitalized adults for empirical treatment of infection. Although piperacillin-tazobactam has been hypothesized to cause acute kidney injury and cefepime has been hypothesized to cause neurological dysfunction, their comparative safety has not been evaluated in a randomized clinical trial.

Objective To determine whether the choice between cefepime and piperacillin-tazobactam affects the risks of acute kidney injury or neurological dysfunction.

Design, Setting, and Participants The Antibiotic Choice on Renal Outcomes (ACORN) randomized clinical trial compared cefepime vs piperacillin-tazobactam in adults for whom a clinician initiated an order for antipseudomonal antibiotics within 12 hours of presentation to the hospital in the emergency department or medical intensive care unit at an academic medical center in the US between November 10, 2021, and October 7, 2022. The final date of follow-up was November 4, 2022.

Interventions Patients were randomized in a 1:1 ratio to cefepime or piperacillin-tazobactam.

Main Outcomes and Measures The primary outcome was the highest stage of acute kidney injury or death by day 14, measured on a 5-level ordinal scale ranging from no acute kidney injury to death. The 2 secondary outcomes were the incidence of major adverse kidney events at day 14 and the number of days alive and free of delirium and coma within 14 days.

Results There were 2511 patients included in the primary analysis (median age, 58 years [IQR, 43-69 years]; 42.7% were female; 16.3% were Non-Hispanic Black; 5.4% were Hispanic; 94.7% were enrolled in the emergency department; and 77.2% were receiving vancomycin at enrollment). The highest stage of acute kidney injury or death was not significantly different between the cefepime group and the piperacillin-tazobactam group; there were 85 patients (n = 1214; 7.0%) in the cefepime group with stage 3 acute kidney injury and 92 (7.6%) who died vs 97 patients (n = 1297; 7.5%) in the piperacillin-tazobactam group with stage 3 acute kidney injury and 78 (6.0%) who died (odds ratio, 0.95 [95% CI, 0.80 to 1.13], P = .56). The incidence of major adverse kidney events at day 14 did not differ between groups (124 patients [10.2%] in the cefepime group vs 114 patients [8.8%] in the piperacillin-tazobactam group; absolute difference, 1.4% [95% CI, −1.0% to 3.8%]). Patients in the cefepime group experienced fewer days alive and free of delirium and coma within 14 days (mean [SD], 11.9 [4.6] days vs 12.2 [4.3] days in the piperacillin-tazobactam group; odds ratio, 0.79 [95% CI, 0.65 to 0.95]).

Conclusions and Relevance Among hospitalized adults in this randomized clinical trial, treatment with piperacillin-tazobactam did not increase the incidence of acute kidney injury or death. Treatment with cefepime resulted in more neurological dysfunction.

Trial Registration ClinicalTrials.gov Identifier:

Introduction

Acutely ill adults presenting to a hospital with suspected infection frequently receive empirical antibiotics. For patients at risk for infection with resistant gram-negative bacteria, guidelines recommend the administration of antipseudomonal antibiotics such as cefepime or piperacillin-tazobactam.1

Quiz Ref IDBecause cefepime and piperacillin-tazobactam have similar activity against many gram-negative bacteria (efficacy), selection between the 2 is likely to depend on differences within their adverse effect profiles (safety). Some observational studies have reported an association between cefepime and neurotoxicity,2-4 ranging from agitation to coma.5 Some observational studies have reported an association between piperacillin-tazobactam and acute kidney injury (AKI), particularly with concurrent receipt of vancomycin.6-8 A randomized clinical trial comparing treatments for methicillin-resistant Staphylococcus aureus found that the addition of an antistaphylococcal β-lactam antibiotic to vancomycin increased the risk of AKI.9 To our knowledge, no randomized clinical trial has compared cefepime vs piperacillin-tazobactam; therefore, it is unknown whether the risks of AKI or neurological dysfunction differ between the 2 drugs.

To compare the safety of cefepime vs piperacillin-tazobactam in adults presenting to the hospital with suspected infection, we conducted the Antibiotic Choice on Renal Outcomes (ACORN) randomized clinical trial.

Methods
Trial Design and Oversight

Between November 10, 2021, and October 7, 2022, we conducted a pragmatic, open-label, parallel-group, randomized comparative safety trial of cefepime vs piperacillin-tazobactam in adult patients with suspected infection in the emergency department (ED) or medical intensive care unit (ICU) at Vanderbilt University Medical Center. The trial was initiated by the investigators, approved by the institutional review board with a waiver of informed consent, registered before enrollment commenced, and overseen by an independent data and safety monitoring board. The trial protocol and statistical analysis plan were published before enrollment concluded10 and appear in Supplement 1.

Patient Population

Adults (≥18 years of age) in the ED or medical ICU for whom a clinician initiated an order for cefepime or piperacillin-tazobactam within 12 hours of presentation to the hospital were eligible. Patients were excluded if they had an allergy to cephalosporins or penicillins, had received more than 1 dose of an antipseudomonal cephalosporin or penicillin within the previous 7 days (patients who had received other antipseudomonal antibiotics were eligible), were incarcerated, or if the treating clinician determined that 1 of the 2 drugs represented a better treatment option for that patient. An electronic health record tool screened all patients for eligibility and an automated alert within the electronic order entry system confirmed patient eligibility with clinicians.

Randomization

Using software within the electronic health record, patients were assigned via simple randomization without stratification in a 1:1 to ratio to receive cefepime or piperacillin-tazobactam (Figure 1). Trial group assignment was concealed until enrollment.

Treatments

A clinical decision support tool in the electronic health record facilitated placement of an order for the assigned antibiotic and recommended a dose and frequency based on the patient’s estimated glomerular filtration rate. Per institutional protocols, the standard administration of cefepime was a 2-g intravenous push over 5 minutes every 8 hours and piperacillin-tazobactam was administered as a 3.375-g bolus over 30 minutes for the initial administration followed by an extended infusion of 3.375 g every 8 hours infused over 4 hours for subsequent doses (additional information appears in the eMethods in Supplement 2). Cefepime was the only antipseudomonal cephalosporin and piperacillin-tazobactam was the only antipseudomonal penicillin available in the trial settings.

Treating clinicians determined the duration of antipseudomonal antibiotic therapy and whether to administer additional antibiotics, such as vancomycin or metronidazole. For the 7 days after enrollment, if treating clinicians discontinued the assigned antibiotic or ordered the unassigned antibiotic, an automated alert reminded them of the trial and recorded the reason for the change. The study ED and ICU were each staffed by a dedicated clinical pharmacist; non-ICU inpatient units were not. Clinical pharmacists remotely monitored drug levels for intravenous vancomycin but not for the β-lactam antibiotics.

Data Collection

Data were collected in routine care and electronically extracted from the electronic health record of the study institution. Data included information on demographics; diagnoses; preenrollment kidney function; medication administration; vital signs; laboratory values; microbiological cultures; organ support therapies; Sequential Organ Failure Assessment score11; Confusion Assessment Method for the ICU (CAM-ICU) score12; Richmond Agitation-Sedation Scale (RASS) score13; Glasgow Coma Scale score14; dates of admission, transfer, and discharge; and vital status at hospital discharge (eMethods in Supplement 2).

Race and ethnicity were self-reported by patients or reported by their surrogates as part of clinical care. Race and ethnicity were automatically extracted from the electronic health record using fixed categories to facilitate assessment of the representativeness of the trial population and the generalizability of the trial results. The frequency of assessments and laboratory measurements were determined by treating clinicians and preexisting clinical protocols. At the study institution, the RASS and Glasgow Coma Scale scores were recorded every 12 hours for all patients and the CAM-ICU score was recorded every 12 hours for patients admitted to the ICU.

Trial personnel adjudicated whether sepsis was present at enrollment using Sepsis-3 criteria,15 the presumed source of infection using previously published categories,16 whether kidney replacement therapy (KRT) had been received, and the indication for KRT.

Outcomes

The primary outcome was the highest stage of AKI or death arising between randomization and day 14, measured on a 5-level ordinal scale. The stages of AKI were defined using the Kidney Disease: Improving Global Outcomes criteria for creatinine level.17 Surviving patients who did not experience new or worsening AKI were assigned a value of 0, those who experienced stage 1 AKI (creatinine level that was 1.5-1.9 times the baseline level or increased by ≥0.3 mg/dL [≥26.5 μmol/L]) were assigned a value of 1, those who experienced stage 2 AKI (creatinine level that was 2.0-2.9 times the baseline level) were assigned a value of 2, and those who experienced stage 3 AKI (creatinine level that was ≥3.0 times the baseline level, AKI with a creatinine level ≥4.0 mg/dL [≥353.7 μmol/L], or receipt of new KRT) were assigned a value of 3. To account for the competing risk of death, patients who died were assigned a value of 4.

The value for baseline creatinine level was determined using a previously described hierarchical approach in which creatinine values obtained during the year before hospitalization were given priority over in-hospital measurements obtained before enrollment and an estimated value was used when no preenrollment measurements were available.18,19 For patients with AKI at enrollment, new AKI was defined as a creatinine level that was at least 0.3-mg/dL greater than the lowest prior creatinine level since enrollment. Patients who had received KRT before enrollment could not experience AKI and received a value of 0 if they survived and 4 if they died. All data were censored at hospital discharge. The primary outcome was selected to assess for an effect of piperacillin-tazobactam on the development of AKI using an international consensus definition over the same period used in prior observational studies.17,20

Two secondary outcomes were prespecified. The first was the proportion of patients who experienced a major adverse kidney event at day 14, which was the composite of death, receipt of new KRT, or persistent kidney dysfunction (final inpatient creatinine level that was ≥2 times the baseline level), and censored at hospital discharge or 14 days after enrollment, whichever occurred first. This outcome was recommended by the National Institute of Diabetes and Digestive and Kidney Diseases work group on clinical trials in AKI as a patient-centered outcome for phase 3 trials, and it is considered more clinically meaningful than outcomes based purely on laboratory values.18,21 The other secondary outcome was the number of days alive and free of delirium and coma within 14 days, which was defined as the number of calendar days on which the patient was alive and without a positive assessment on the CAM-ICU12 or a RASS13 score of −4 or −5, and censored at hospital discharge. This outcome was selected to assess the effect of cefepime on the development of neurological dysfunction using a common measure of neurological function among acutely ill adults22-24 (eMethods in Supplement 2).

Statistical Analysis

Details regarding the sample size estimation and reestimation have been reported previously.10 The trial was initially designed to enroll 2050 patients to provide 80% statistical power to detect an odds ratio (OR) of 0.65 in the primary analysis (eMethods in Supplement 2). Because the association between piperacillin-tazobactam and AKI has been hypothesized to be conditioned on concurrent receipt of vancomycin6-8 and the timing of the trial’s interim analysis, 75% of patients in the trial population were receiving vancomycin at enrollment; therefore, the data and safety monitoring board recommended increasing the sample size from 2050 to 2500 patients. Assuming a 2-sided α of .05 and a distribution of the primary outcome with approximately 70% of patients experiencing no AKI, 10% experiencing stage 1 AKI, 7% experiencing stage 2 AKI, 7% experiencing stage 3 AKI, and 6% experiencing death, we calculated that enrollment of 2500 patients would provide 92% statistical power to detect an OR of 0.75 in the primary analysis. An OR of 0.75 would equate to an absolute between-group difference of 5% in patients who experienced AKI of any stage or death.

The primary analysis population included all randomized patients who received at least 1 dose of either cefepime or piperacillin-tazobactam, analyzed in the group to which they were assigned. The primary analysis compared trial groups using an unadjusted proportional odds regression model with between-group differences expressed using an unadjusted OR and 95% CI, for which values less than 1.0 indicate a lower odds of AKI or death with cefepime compared with piperacillin-tazobactam. Major adverse kidney events were compared between groups using an unadjusted logistic regression model. Days alive and free of delirium and coma were compared between groups using an unadjusted proportional odds regression model.

As a secondary analysis, an adjusted analysis of the primary outcome was performed using a multivariable proportional odds regression model with prespecified baseline covariates including age, sex, baseline creatinine level, prior receipt of KRT, receipt of vasopressors, receipt of mechanical ventilation, Sequential Organ Failure Assessment score, presumed source of infection, and location at enrollment. Similar variables were used for the adjusted analyses of the secondary outcomes.

Prespecified sensitivity analyses included (1) an analysis of all enrolled patients, including those who never received cefepime or piperacillin-tazobactam; (2) an analysis restricted to patients who received treatment with cefepime or piperacillin-tazobactam for more than 48 hours (greater exposure to the antibiotics under study); (3) an analysis removing race as a variable in the equation to calculate creatinine for those without measurement of creatinine level prior to the current illness; (4) an analysis restricted to patients with a measured creatinine level prior to the current hospitalization; and (5) an analysis using only the preillness creatinine level as the baseline creatinine level.

In accordance with published guidelines,25 we examined whether the prespecified baseline variables modified the effect of trial group assignment on the primary and secondary outcomes using models with independent variables for each trial group, the proposed effect modifier, and the interaction between the 2 (eMethods in Supplement 2). The baseline variables prespecified as potential effect modifiers included presence of sepsis, source of infection, receipt of vancomycin on the day of enrollment, chronic kidney disease, presence and stage of AKI at enrollment, and admitting service (medical or surgical).

When data were missing for the secondary or exploratory outcomes, a complete case analysis was performed, excluding cases in which data were missing for the analyzed outcome. Missing data were not imputed for these outcomes (eMethods in Supplement 2).

The data and safety monitoring board reviewed a single planned interim analysis after enrollment of the first 1025 patients, with a stopping boundary of P ≤ .001 for the between-group difference in the primary outcome. For the final analysis of the primary outcome, a 2-sided P value of less than .05 was considered to indicate statistical significance.26 Between-group differences in the secondary and exploratory outcomes are reported as point estimates and 95% CIs. The widths of the 95% CIs for the secondary analyses were not adjusted for multiplicity and should not be used to infer definitive between-group differences in the treatment effects. All analyses were performed with R version 4.2.2 (R Foundation for Statistical Computing).

Results
Trial Population

Among 3806 patients who met inclusion criteria, 1172 (30.8%) were excluded. Of the 2634 patients (69.2%) enrolled, 4 (0.2%) were incarcerated and excluded from subsequent data collection and analysis and 119 (4.5%) did not receive a dose of cefepime or piperacillin-tazobactam during the 7 days after enrollment and were not included in the primary analysis. A total of 2511 patients (95.3%) were included in the primary analysis (Figure 1). The median age was 58 years (IQR, 43-69 years), 2378 patients (94.7%) were enrolled in the ED, and the median time between presentation to the hospital and enrollment was 1.2 hours (IQR, 0.4-3.5 hours). At the time of enrollment, 1362 patients (54.2%) had sepsis and the most common suspected sources of infection were intra-abdominal and pulmonary. A total of 1214 patients (48.3%) in the cefepime group and 1297 patients (51.7%) in the piperacillin-tazobactam group were included in the primary analysis (Table 1 and eTables 1-6 in Supplement 2). The final date of follow-up was November 4, 2022.

Antibiotic Therapy

In the 14 days after enrollment, 1154 of 1214 patients (95.1%) in the cefepime group received at least 1 dose of cefepime and 1276 of 1297 patients (98.4%) in the piperacillin-tazobactam group received at least 1 dose of piperacillin-tazobactam. Patients received the assigned antibiotic for a median of 3 days (IQR, 1-4 days) in each group (Figure 2 and eFigures 1-2 and eTables 7-8 in Supplement 2). In the 14 days after enrollment, 228 of 1214 patients (18.8%) in the cefepime group received at least 1 dose of piperacillin-tazobactam and 223 of 1297 patients (17.2%) in the piperacillin-tazobactam group received at least 1 dose of cefepime. A total of 85 patients (7.0%) in the cefepime group and 92 patients (7.1%) in the piperacillin-tazobactam group received other extended-spectrum gram-negative antibiotics, most commonly an aminoglycoside or carbapenem.

A total of 942 patients (77.6%) in the cefepime group and 997 patients (76.9%) in the piperacillin-tazobactam group were receiving intravenous vancomycin at the time of enrollment. In the first 14 days, at least 1 dose of vancomycin was received by 1004 patients (82.7%) in the cefepime group and 1049 patients (80.9%) in the piperacillin-tazobactam group. Patients received vancomycin for a median duration of 2 days (IQR, 1-4 days).

Primary Outcome

The highest stage of AKI or death by day 14 did not significantly differ between the cefepime group and the piperacillin-tazobactam group (OR, 0.95 [95% CI, 0.80 to 1.13], P = .56; Table 2 and eTable 9 and eFigures 3-6 in Supplement 2). Of the 2511 patients included in the primary outcome analysis, 75.0% in the cefepime group (910 of 1214) vs 73.4% in the piperacillin-tazobactam group (952 of 1297) did not die or experience AKI of any stage by day 14; 7.1% (n = 86) vs 7.7% (n = 100), respectively, experienced stage 1 AKI; 3.4% (n = 41) vs 5.4% (n = 70) experienced stage 2 AKI; 7.0% (n = 85) vs 7.5% (n = 97) experienced stage 3 AKI; and 7.6% (n = 92) vs 6.0% (n = 78) died.

The results were similar in the adjusted analyses and in all the prespecified sensitivity analyses, including among the intention-to-treat population of all enrolled patients and the analysis limited to the 1798 patients who received at least 48 hours of antipseudomonal antibiotic therapy (eTables 10-11 in Supplement 2). The results were also similar in all the post hoc analyses, including an analysis limited to patients who received at least 72 hours of antipseudomonal antibiotic therapy, an analysis limited to patients who received at least 96 hours of antipseudomonal antibiotic therapy, and an analysis excluding patients who were receiving KRT or who had AKI at enrollment (eTables 11-13 in Supplement 2). The results of the prespecified subgroup analyses appear in Figure 3 and eTable 14 in Supplement 2.

Secondary Outcomes

Quiz Ref IDA total of 124 patients (10.2%) in the cefepime group and 114 patients (8.8%) in the piperacillin-tazobactam group experienced a major adverse kidney event at day 14 (absolute difference, 1.4% [95% CI, −1.0% to 3.8%]; eTable 15 in Supplement 2). Quiz Ref IDPatients in the cefepime group experienced fewer days alive and free of delirium and coma within 14 days compared with patients in the piperacillin-tazobactam group (mean, 11.9 [SD, 4.6] days vs 12.2 [SD, 4.3] days, respectively; OR, 0.79 [95% CI, 0.65 to 0.95]), consistent with a greater burden of delirium, coma, or death in the cefepime group compared with the piperacillin-tazobactam group.

A total of 252 patients (20.8%) in the cefepime group experienced coma or delirium between enrollment and day 14 compared with 225 patients (17.3%) in the piperacillin-tazobactam group (absolute difference, 3.4% [95% CI, 0.3%-6.6%]). The results were similar in the post hoc analyses of days alive and free of delirium and coma within 14 days, adjusting for receipt of sedation at enrollment (OR, 0.78 [95% CI, 0.62-0.99]), baseline delirium and coma (OR, 0.80 [95% CI, 0.63-1.01]), and using alternative definitions of delirium and coma (eTables 16-20 in Supplement 2). The subgroup analyses of the secondary outcomes appear in Figure 3 and eTables 21-22 in Supplement 2.

Exploratory Outcomes

The trial groups did not differ with regard to the highest stage of AKI or death at 7 days (OR, 0.99 [95% CI, 0.82 to 1.19]) or major adverse kidney events at 7 days (absolute difference, 1.8% [95% CI, −0.4% to 3.9%]). Death by day 28 occurred in 104 patients (8.6%) in the cefepime group and 106 patients (8.2%) in the piperacillin-tazobactam group (absolute difference, 0.4% [95% CI, −1.9% to 2.6%]). Kidney replacement therapy was initiated by day 28 in 44 patients (3.9%) in the cefepime group and 28 patients (2.3%) in the piperacillin-tazobactam group (absolute difference, 1.6% [95% CI, 0.1% to 3.1%]). Indications for KRT were similar between groups (eTable 23 in Supplement 2). Additional exploratory outcomes, allergic drug reactions, and adverse events appear in Table 2 and eTables 24-28 in Supplement 2.

Discussion

Among adults presenting to the hospital with suspected infection in this pragmatic trial, the highest stage of AKI or death did not differ between patients randomized to cefepime or piperacillin-tazobactam. Patients randomized to cefepime experienced more neurological dysfunction, as measured by the number of days alive and free of delirium and coma.

Prior preclinical and observational studies of the relationship between piperacillin-tazobactam and AKI have yielded conflicting results. Preclinical studies found piperacillin-tazobactam decreased the secretion of creatinine into the urine and increased creatinine levels in the blood by inhibiting organic anion transporters 1 and 3 on kidney tubular cells without affecting glomerular filtration rate as measured by cystatin C.27,28 Piperacillin-tazobactam was protective against vancomycin-induced AKI in animal models.29,30

In contrast, some observational studies reported an association between piperacillin-tazobactam and AKI in hospitalized adults, particularly with concurrent receipt of vancomycin, prompting the US Food and Drug Administration to add the following statement to the package insert for piperacillin-tazobactam: “co-administration of [piperacillin-tazobactam] with vancomycin may increase the incidence of acute kidney injury.”31 The potential for indication bias and unmeasured confounding in prior observational studies was addressed by the randomized clinical trial design of the current study.

Piperacillin-tazobactam did not appear to affect the risk of AKI at any of the measured time points, overall, or among the 1939 patients receiving vancomycin at enrollment. We included patients with preexisting AKI at enrollment because these patients are at high risk of worsening kidney injury and death, outcomes that could be affected by the choice of antibiotics. The results were similar, however, in the analyses in which these patients were excluded.

Cefepime crosses the blood-brain barrier,32 exhibits concentration-dependent inhibition of γ-amino butyric acid receptors,33 and has been reported in case series and cohort studies to be associated with neurotoxicity, including coma, delirium, encephalopathy, and seizures.34 Neurotoxicity with cefepime has been reported to occur more commonly among patients with impaired kidney function and conditions that disrupt the blood-brain barrier, such as sepsis.34-36 In the current trial, patients in the cefepime group experienced fewer days alive and free of delirium and coma than patients in the piperacillin-tazobactam group. Available data from preclinical studies, observational studies, and the current randomized clinical trial suggest that cefepime may modestly increase the risk of neurological dysfunction in hospitalized adults.

This trial has several strengths. A large randomized clinical trial embedded within real-world clinical care through the electronic health record represents a rigorous approach to comparing the safety of 2 commonly used, effective treatment options.37 The trial design included randomization to balance baseline characteristics, concealment of group assignment until enrollment to prevent selection bias, and enrollment occurring at a median of 1 hour after hospital presentation to minimize exposure to antibiotics prior to enrollment. The sample size permitted precise estimates of treatment effect, overall, and among the 1939 patients receiving concurrent vancomycin at enrollment.

Limitations

This trial has several limitations. First, conducting a trial at a single academic center may limit generalizability. Second, patients and clinicians were not blinded to group assignment, which could have affected clinical assessments like RASS and CAM-ICU or the frequency of laboratory measurements like creatinine, although the number of clinical and laboratory assessments appeared to be similar between groups.

Third, almost 1 in 5 patients in each group received a least 1 dose of the unassigned antibiotic within the first 14 days, which decreases the separation between groups and increases the risk of failing to detect a true between-group difference in the outcomes (type II error). Fourth, a preillness creatinine measure was not available for all patients, although creatinine level was available prior to or at enrollment for 99% of patients and the results were similar in the analyses restricted to patients with available measurements.

Fifth, outcome assessment was censored at hospital discharge. Sixth, patients in the trial received a median of only 3 days of treatment with cefepime or piperacillin-tazobactam; however, the outcomes were similar among the 1798 patients who received longer courses of therapy. Seventh, the current trial collected data on delirium and coma, but not other types of neurological dysfunction that might be attributed to cefepime, such as agitation, myoclonus, and seizures.

Eighth, unlike trials evaluating the effect of 1 treatment on a single efficacy outcome, the current trial compared 2 treatments with regard to 2 safety outcomes (kidney injury and neurological dysfunction), which may increase the risk of type I error but for which guidance on addressing multiplicity is lacking.38 Ninth, in the setting of this trial, piperacillin-tazobactam was administered as an extended infusion. These results may be less informative in settings that use a different approach.

Conclusion

Among hospitalized adults in this randomized clinical trial, treatment with piperacillin-tazobactam did not increase the incidence of AKI or death. Treatment with cefepime resulted in more neurological dysfunction.

Section Editor: Christopher Seymour, MD, Associate Editor, JAMA (christopher.seymour@jamanetwork.org).
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Article Information

Accepted for Publication: September 21, 2023.

Published Online: October 14, 2023. doi:10.1001/jama.2023.20583

Corresponding Author: Edward T. Qian, MD, MSc, Vanderbilt University Medical Center, 1161 21st Ave S, Nashville, TN 37232 (edward.t.qian@vumc.org).

Author Contributions: Dr Qian had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Drs Semler and Rice contributed equally.

Concept and design: Qian, Casey, A. Wright, Wang, Stollings, Nelson, P. Wright, Siew, Wrenn, Andereck, Han, Self, Semler, Rice.

Acquisition, analysis, or interpretation of data: Qian, Casey, A. Wright, Wang, Shotwell, Siemann, Dear, Stollings, Lloyd, Marvi, Seitz, Nelson, Siew, Dennis, Wrenn, Andereck, Han, Self, Semler, Rice.

Drafting of the manuscript: Qian, Casey, Nelson, Semler.

Critical review of the manuscript for important intellectual content: All authors.

Statistical analysis: Casey, Wang, Shotwell, Seitz, Nelson, Semler.

Obtained funding: Qian, Semler.

Administrative, technical, or material support: Casey, A. Wright, Siemann, Dear, Stollings, Marvi, Seitz, Wrenn, Andereck, Self, Semler, Rice.

Supervision: Casey, A. Wright, Nelson, P. Wright, Dennis, Han, Self, Semler, Rice.

Conflict of Interest Disclosures: Dr Casey reported receiving a travel grant from Fisher & Paykel Healthcare to speak at conference. Dr P. Wright reported receiving travel support from the Infectious Diseases Society of America for travel to the national meeting and for being a committee member. Dr Siew reported receiving personal fees from the American Society of Nephrology for serving on its editorial board and from Novartis for serving on a data and safety monitoring board and receiving royalties from UptoDate. Dr Dennis reported receiving travel support as the chair of the Eastern Association for Surgery of Trauma annual scientific assembly committee. Dr Wrenn reported receiving unrelated research support from Bristol Myers Squibb. Dr Semler reported serving as an advisory board member for Baxter International. Dr Rice reported receiving honoraria from the American College of Chest Physicians and the American Society of Parenteral and Enteral Nutrition and personal fees from Cumberland Pharmaceuticals, Cytovale, and Sanofi. No other disclosures were reported.

Funding/Support: Drs Qian and Seitz were supported by grant T32HL087738-17 from the National Heart, Lung, and Blood Institute. Dr Casey was supported in part by grant K23HL153584 from the National Heart, Lung, and Blood Institute and grants from the National Institutes of Health and the US Department of Defense. The project was supported by the Vanderbilt Institute for Clinical and Translational Research and the Vanderbilt Center for Learning Healthcare under Vanderbilt Clinical and Translational Science awards 5UL1 TR002243-07 and 1U24TR004437 from the National Center for Advancing Translational Sciences (supported the work of Ms Wang and Drs Siemann, Dear, Self, Semler, and Rice). Dr Shotwell was supported by grants R18HS025910, R01HL164909, R01HL161635, R35GM145375, R18HS026158, R18HS026616, R33HL155810, VUMC91864/OT2HL156812, and U01HL168478 from the National Institutes of Health. Dr Siew was supported by grant P30-DK114809 from the Vanderbilt O’Brien Kidney Center. Dr Semler was supported by grant K23HL143053 from the National Heart, Lung, and Blood Institute. Dr Rice was supported by grants UL1 RR 024975 and U24 TR 001608 from the National Center for Advancing Translational Science.

Role of the Funder/Sponsor: The funders/sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Group Information: The members of the Vanderbilt Center for Learning Healthcare and the Pragmatic Critical Care Research Group appear in Supplement 3.

Disclaimer: The views expressed in this article are those of the authors and do not necessarily reflect the official views of the National Center for Advancing Translational Sciences or the National Institutes of Health.

Meeting Presentation: Presented in part at IDWeek 2023, a joint annual meeting of the Infectious Diseases Society of America, the Society for Healthcare Epidemiology of America, the HIV Medicine Association, the Pediatric Infectious Diseases Society, and the Society of Infectious Diseases Pharmacists; October 14, 2023; Boston, Massachusetts.

Data Sharing Statement: See Supplement 4.

References
1.
Evans L, Rhodes A, Alhazzani W, et al. Surviving sepsis campaign: international guidelines for management of sepsis and septic shock 2021. Intensive Care Med. 2021;47(11):1181-1247. doi:
2.
Abanades S, Nolla J, Rodríguez-Campello A, Pedro C, Valls A, Farré M. Reversible coma secondary to cefepime neurotoxicity. Ann Pharmacother. 2004;38(4):606-608. doi:
3.
Balderia PG, Chandorkar A, Kim Y, Patnaik S, Sloan J, Newman GC. Dosing cefepime for renal function does not completely prevent neurotoxicity in a patient with kidney transplant. J Patient Saf. 2018;14(2):e33-e34. doi:
4.
Drago L, De Vecchi E. The safety of cefepime in the treatment of infection. Expert Opin Drug Saf. 2008;7(4):377-387. doi:
5.
Appa AA, Jain R, Rakita RM, Hakimian S, Pottinger PS. Characterizing cefepime neurotoxicity: a systematic review. Open Forum Infect Dis. 2017;4(4):ofx170. doi:
6.
Bellos I, Karageorgiou V, Pergialiotis V, Perrea DN. Acute kidney injury following the concurrent administration of antipseudomonal β-lactams and vancomycin: a network meta-analysis. Clin Microbiol Infect. 2020;26(6):696-705. doi:
7.
Blevins AM, Lashinsky JN, McCammon C, Kollef M, Micek S, Juang P. Incidence of acute kidney injury in critically ill patients receiving vancomycin with concomitant piperacillin-tazobactam, cefepime, or meropenem. Antimicrob Agents Chemother. 2019;63(5):e02658-18. doi:
8.
O’Callaghan K, Hay K, Lavana J, McNamara JF. Acute kidney injury with combination vancomycin and piperacillin-tazobactam therapy in the ICU: a retrospective cohort study. Int J Antimicrob Agents. 2020;56(1):106010. doi:
9.
Tong SYC, Lye DC, Yahav D, et al; Australasian Society for Infectious Diseases Clinical Research Network. Effect of vancomycin or daptomycin with vs without an antistaphylococcal β-lactam on mortality, bacteremia, relapse, or treatment failure in patients with MRSA bacteremia: a randomized clinical trial. Ѵ. 2020;323(6):527-537. doi:
10.
Qian ET, Casey JD, Wright A, et al; Vanderbilt Learning Healthcare System Platform Investigators. Protocol and statistical analysis plan for the Antibiotic Choice On ReNal outcomes (ACORN) randomised clinical trial. Ѵ Open. 2023;13(3):e066995. doi:
11.
Seymour CW, Liu VX, Iwashyna TJ, et al. Assessment of clinical criteria for sepsis: for the third international consensus definitions for sepsis and septic shock (Sepsis-3). Ѵ. 2016;315(8):762-774. doi:
12.
Ely EW, Inouye SK, Bernard GR, et al. Delirium in mechanically ventilated patients: validity and reliability of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Ѵ. 2001;286(21):2703-2710. doi:
13.
Sessler CN, Gosnell MS, Grap MJ, et al. The Richmond Agitation-Sedation Scale: validity and reliability in adult intensive care unit patients. Am J Respir Crit Care Med. 2002;166(10):1338-1344. doi:
14.
Teasdale G, Jennett B. Assessment of coma and impaired consciousness: a practical scale. Գ. 1974;2(7872):81-84. doi:
15.
Singer M, Deutschman CS, Seymour CW, et al. The third international consensus definitions for sepsis and septic shock (Sepsis-3). Ѵ. 2016;315(8):801-810. doi:
16.
Leligdowicz A, Dodek PM, Norena M, Wong H, Kumar A, Kumar A; Co-operative Antimicrobial Therapy of Septic Shock Database Research Group. Association between source of infection and hospital mortality in patients who have septic shock. Am J Respir Crit Care Med. 2014;189(10):1204-1213. doi:
17.
Kidney Disease Improving Global Outcomes (KDIGO) Acute Kidney Injury Work Group. KDIGO clinical practice guideline for acute kidney injury. Kidney Int Suppl. 2012;2(1):1-138. doi:
18.
Semler MW, Rice TW, Shaw AD, et al. Identification of major adverse kidney events within the electronic health record. J Med Syst. 2016;40(7):167. doi:
19.
Semler MW, Self WH, Wanderer JP, et al; SMART Investigators and the Pragmatic Critical Care Research Group. Balanced crystalloids versus saline in critically ill adults. N Engl J Med. 2018;378(9):829-839. doi:
20.
Colantuoni E, Scharfstein DO, Wang C, et al. Statistical methods to compare functional outcomes in randomized controlled trials with high mortality. Ѵ. 2018;360:j5748. doi:
21.
Palevsky PM, Molitoris BA, Okusa MD, et al. Design of clinical trials in acute kidney injury: report from an NIDDK workshop on trial methodology. Clin J Am Soc Nephrol. 2012;7(5):844-850. doi:
22.
Andersen-Ranberg NC, Poulsen LM, Perner A, et al; AID-ICU Trial Group. Haloperidol for the treatment of delirium in ICU patients. N Engl J Med. 2022;387(26):2425-2435. doi:
23.
Girard TD, Exline MC, Carson SS, et al; MIND-USA Investigators. Haloperidol and ziprasidone for treatment of delirium in critical illness. N Engl J Med. 2018;379(26):2506-2516. doi:
24.
Qian ET, Wang L, Stollings JL, Casey JD, Rice TW, Semler MW. Piperacillin-tazobactam versus anti-pseudomonal cephalosporins and renal and neurologic outcomes in critically ill adults: a secondary analysis of the SMART Trial. J Intensive Care Med. Published online June 26, 2023. doi:
25.
Schandelmaier S, Briel M, Varadhan R, et al. Development of the Instrument to assess the Credibility of Effect Modification Analyses (ICEMAN) in randomized controlled trials and meta-analyses. Ѵ. 2020;192(32):E901-E906. doi:
26.
Peto R, Pike MC, Armitage P, et al. Design and analysis of randomized clinical trials requiring prolonged observation of each patient, I: introduction and design. Br J Cancer. 1976;34(6):585-612. doi:
27.
Wen S, Wang C, Duan Y, et al. OAT1 and OAT3 also mediate the drug-drug interaction between piperacillin and tazobactam. Int J Pharm. 2018;537(1-2):172-182. doi:
28.
Miano TA, Hennessy S, Yang W, et al. Association of vancomycin plus piperacillin-tazobactam with early changes in creatinine versus cystatin C in critically ill adults: a prospective cohort study. Intensive Care Med. 2022;48(9):1144-1155. doi:
29.
Chang J, Pais GM, Valdez K, Marianski S, Barreto EF, Scheetz MH. Glomerular function and urinary biomarker changes between vancomycin and vancomycin plus piperacillin-tazobactam in a translational rat model. Antimicrob Agents Chemother. 2022;66(3):e0213221. doi:
30.
Pais GM, Liu J, Avedissian SN, et al. Lack of synergistic nephrotoxicity between vancomycin and piperacillin/tazobactam in a rat model and a confirmatory cellular model. J Antimicrob Chemother. 2020;75(5):1228-1236. doi:
31.
Pfizer Injectables. ZOSYN (piperacillin and tazobactam) for injection. Published May 2017. Accessed June 7, 2023.
32.
Durand-Maugard C, Lemaire-Hurtel AS, Gras-Champel V, et al. Blood and CSF monitoring of cefepime-induced neurotoxicity: nine case reports. J Antimicrob Chemother. 2012;67(5):1297-1299. doi:
33.
Sugimoto M, Uchida I, Mashimo T, et al. Evidence for the involvement of GABA(A) receptor blockade in convulsions induced by cephalosporins. ܰDZ󲹰DZDz. 2003;45(3):304-314. doi:
34.
Payne LE, Gagnon DJ, Riker RR, et al. Cefepime-induced neurotoxicity: a systematic review. Crit Care. 2017;21(1):276. doi:
35.
Boschung-Pasquier L, Atkinson A, Kastner LK, et al. Cefepime neurotoxicity: thresholds and risk factors: a retrospective cohort study. Clin Microbiol Infect. 2020;26(3):333-339. doi:
36.
Lee SJ. Cefepime-induced neurotoxicity. J Neurocritical Care. 2019;12(2):74-84. doi:
37.
Mani N, Murray J, Gulick RM, et al. Novel clinical trial designs for the development of new antiretroviral agents. ٳ. 2012;26(8):899-907. doi:
38.
US Department of Health and Human Services. Multiple endpoints in clinical trials guidance for industry. Published January 2017. Accessed June 7, 2023.
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