A Cluster of Cefepime-induced Neutropenia During Outpatient Parenteral Antimicrobial Therapy

Pharmacokinetics of YK-1169 in healthy subjects and pharmacokinetic/pharmacodynamic analysis by Monte Carlo simulation

OBJECTIVE

This study (NCT05588531) aimed to evaluate the safety and pharmacokinetics of cefepime-avibactam (YK-1169) in healthy Chinese subjects and explore the optimal regimen for treating carbapenem-resistant Klebsiella pneumoniae (CRKP) based on the pharmacokinetic/pharmacodynamic evaluation.

METHODS

YK-1169 single-ascending doses (0.5, 1.25, 2.5 or 3.75 g, 2-h infusion) and multiple doses (2.5 or 3.75 g every 8 h [q8h], 2-h infusion) given for 7 days were evaluated in pharmacokinetic studies. Subjects were randomized to receive cefepime (2 g), avibactam (0.5 g) or YK-1169 (2.5 g) to assess drug-drug interactions. The minimum inhibitory concentrations (MICs) of YK-1169 were determined by the broth microdilution method. Monte Carlo simulation was used to evaluate 10 different dose regimens.

RESULTS

Cefepime and avibactam both showed a linear pharmacokinetic profile. No accumulation was found after multiple doses. The cefepime Cmax,ss and AUC0-∞,ss were 9.20 and 16.0 μg/mL, 407.2 and 659.45 μg·h/mL in the 2.5 and 3.75 g multiple-dose groups, respectively. The avibactam Cmax,ss and AUC0-∞,ss were 0.545 and 0.837 μg/mL, 53.31 and 79.55 μg·h/mL in the 2.5 and 3.75 g multiple-dose groups, respectively. Cefepime and avibactam did not affect each other's pharmacokinetics. No serious adverse events occurred. All regimens achieved 90% probability of target attainment (PTA) goals when the MIC was ≤8 mg/L. The regimens of 2.5 (q8h, 2-h infusion), 3.75 (q8h, 2-, 3- and 4-h infusions) and 7.5 g (24-h continuous infusion) reached a 90% cumulative fraction of response.

CONCLUSION

YK-1169 had good antibacterial activity against CRKP and could be an option for CRKP infections. The regimen of 2.5 g q8h intravenously guttae (ivgtt) 2 h should be considered in future clinical trials.

Outcomes of Intravenous Push versus Intermittent Infusion Administration of Cefepime in Critically Ill Patients

The equivalence of intravenous push (IVP) and piggyback (IVPB) administration has not been evaluated in the critically ill population for most medications, but it is especially relevant for antibiotics, such as cefepime, that exhibit time-dependent bactericidal activity. A single center, retrospective, observational pre/post-protocol change study included critically ill adults who received cefepime as empiric therapy between August 2015 and 2021. The primary outcome was treatment failure, which was defined as a composite of escalation of antibiotic regimen or all-cause mortality. Secondary outcomes included adverse drug events, days of cefepime therapy, total days of antibiotic therapy, and ICU and hospital length of stay. Outcomes were compared using Chi-squared, Mann Whitney U, and binary logistic regression as appropriate. A total of 285 patients were included: 87 IVPB and 198 IVP. Treatment failure occurred in 18% (n = 16) of the IVPB group and 27% (n = 54) of the IVP group (p = 0.109). There were no significant differences in secondary outcomes. Longer duration of antibiotics (odds ratio [OR] 1.057, 95% confidence interval [CI] 1.013-1.103), SOFA score (OR 1.269, 95% CI 1.154-1.397) and IVP administration of cefepime (OR 2.370, 95% CI 1.143-4.914) were independently associated with treatment failure. Critically ill patients who received IVP cefepime were more likely to experience treatment failure in an adjusted analysis. The current practice of IVP cefepime should be reevaluated, as it may not provide similar clinical outcomes in the critically ill population.

The Rare Adverse Effect of Cefepime-Induced Neutropenia

Cefepime is widely considered a safe and effective antibiotic, but it can have rare and serious side effects. We present a case of a 33-year-old female patient who developed severe and potentially life-threatening neutropenia after being on cefepime for 25 days. Despite extensive investigations, no other causes of neutropenia could be identified. Discontinuing the medication and administering a single dose of filgrastim produced a rapid and dramatic response. This case highlights the rare but serious risk of cefepime-induced neutropenia and underscores the need for clinicians to remain vigilant for this potential adverse effect. It is important to note that discontinuing the medication can rapidly reverse the effects, making timely recognition and intervention crucial for patient outcomes.

A review of evidence, antimicrobial stability, and feasibility considerations for OPAT continuous infusion

Outpatient parenteral antimicrobial therapy (OPAT) has been widely used in clinical practice for many decades because of its associated cost savings, reductions in inpatient hospital days, and decreases in hospital-associated infections. Despite this long history, evolving practice patterns and new drug delivery devices continue to present challenges as well as opportunities for clinicians when designing appropriate outpatient antimicrobial regimens. One such change is the increasing use of extended and continuous infusion (CI) of antimicrobials to optimize the achievement of pharmacokinetic and pharmacodynamic targets. Elastomeric devices are also becoming increasingly popular in OPAT, including for the delivery of CI. In this article, we review the clinical evidence for CI in OPAT, as well as practical considerations of patient preferences, cost, and antimicrobial stability.

Pushing the agenda for intravenous push administration in outpatient parenteral antimicrobial therapy

Intravenous push (IVP) antimicrobial administration refers to rapid bolus infusion of medication. This drug delivery method offers improved patient convenience, superior patient and nursing satisfaction, and cost savings when used in outpatient parenteral antimicrobial therapy (OPAT). Antimicrobial agents must demonstrate optimal physiochemical and pharmacologic characteristics, as well as sufficient syringe stability, to be administered in this manner. Additionally, impacts on medication tolerability, patient safety, and effectiveness must be considered. This narrative review summarizes the available data and practical implications of IVP administration of antimicrobials in the OPAT setting.

Cefepime-Induced Neutropenia: A Case Report and Literature Review

Cefepime is a fourth-generation cephalosporin utilized in treatment of multiple Gram-negative and -positive infections. The current report presents a case of 50-year-old man admitted with epidural abscess who developed neutropenia after prolonged use of cefepime. The neutropenia developed after 24 days of cefepime treatment and resolved 4 days after cessation of cefepime. Assessment of the patient's profile indicated no other possible cause for neutropenia. A literature review was done, and is presented herein to compare and identify the pattern of cefepime-induced neutropenia in 15 patients. The data presented in this article highlight that despite its rarity, cefepime-induced neutropenia should be considered by clinicians when planning a prolonged course of cefepime.

Clinical Pharmacokinetics and Pharmacodynamics of Cefepime

Cefepime is a broad-spectrum fourth-generation cephalosporin with activity against Gram-positive and Gram-negative pathogens. It is generally administered as an infusion over 30-60 min or as a prolonged infusion with infusion times from 3 h to continuous administration. Cefepime is widely distributed in biological fluids and tissues with an average volume of distribution of ~ 0.2 L/kg in healthy adults with normal renal function. Protein binding is relatively low (20%), and elimination is mainly renal. About 85% of the dose is excreted unchanged in the urine, with an elimination half-life of 2-2.3 h. The pharmacokinetics of cefepime is altered under certain pathophysiological conditions, resulting in high inter-individual variability in cefepime volume of distribution and clearance, which poses challenges for population dosing approaches. Consequently, therapeutic drug monitoring of cefepime may be beneficial in certain patients including those who are critically ill, have life-threatening infections, or are infected with more resistant pathogens. Cefepime is generally safe and efficacious, with a goal exposure target of 70% time of the free drug concentration over the minimum inhibitory concentration for clinical efficacy. In recent years, reports of neurotoxicity have increased, specifically in patients with impaired renal function. This review summarizes the pharmacokinetics, pharmacodynamics, and toxicodynamics of cefepime contemporarily in the setting of increasing cefepime exposures. We explore the potential benefits of extended or continuous infusions and therapeutic drug monitoring in special populations.

A Review of β-Lactam-Associated Neutropenia and Implications for Cross-reactivity

OBJECTIVE

To review the incidence, management, and current understanding of the pathophysiology of β-lactam-induced neutropenia and to critically evaluate the practicality and safety of direct substitution to an alternative β-lactam in the setting of this reaction.

DATA SOURCES

A literature analysis using the PubMed and Ovid search engines (July 1968 to October 2020) was performed using the search terms neutropenia, leukopenia, β-lactam, nonchemotherapy, agranulocytosis, and G-CSF (granulocyte colony-stimulating factor).

STUDY SELECTION AND DATA EXTRACTION

The included English-language studies evaluated the incidence, mechanism, and/or management of β-lactam-induced neutropenia in pediatric or adult patients.

DATA SYNTHESIS

Drug-induced neutropenia is a well-documented adverse reaction of β-lactam antibiotics, with an incidence of approximately 10% following at least 2 weeks of intravenous therapy. However, multiple gaps in knowledge remain in the mechanism of pathophysiology and optimal management of this reaction. Both direct toxic and immune-mediated mechanisms have been implicated. Although the cornerstone of management includes cessation of the offending agent, controversy exists on the appropriateness of direct substitution or future use of an alternative β-lactam.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Given the frequency of use and superiority of β-lactams over alternative therapy for several infectious disease states, practical recommendations are needed on the management and safe use of β-lactams following β-lactam-induced neutropenia.

CONCLUSION

Future use of β-lactams with differing R1 side chains, particularly those from a separate class, should not be deemed contraindicated following β-lactam-induced neutropenia and may be considered when indicated, with close laboratory monitoring.