Towards optimizing cefepime/tazobactam (WCK 4282) exposure to achieve efficacy against piperacillin/tazobactam-resistant ESBL infections: dose recommendations for various renal functions, including intermittent haemodialysis, in healthy individuals

OBJECTIVES

WCK 4282 is a novel combination of cefepime 2 g and tazobactam 2 g being developed for the treatment of infections caused by piperacillin/tazobactam-resistant ESBL infections. The dosing regimen for cefepime/tazobactam needs to be optimized to generate adequate exposures to treat infections caused by ESBL-producing pathogens resistant to both cefepime and piperacillin/tazobactam.

METHODS

We developed pharmacokinetic population models of cefepime and tazobactam to evaluate the optimal dose adjustments in patients, including those with augmented renal clearance as well as various degrees of renal impairment, and also for those on intermittent haemodialysis. Optimal doses for various degrees of renal function were identified by determining the PTA for a range of MICs. To cover ESBL-producing pathogens with an cefepime/tazobactam MIC of 16 mg/L, a dosing regimen of 2 g q8h infused over 1.5 h resulted in a combined PTA of 99% for the mean murine 1 log10-kill target for the cefepime/tazobactam combination.

RESULTS

We found that to adjust for renal function, doses need to be reduced to 1 g q8h, 500 mg q8h and 500 mg q12h for patients with CLCR of 30-59, 15-29 and 8-14 mL/min (as well as patients with intermittent haemodialysis), respectively. In patients with high to augmented CLR (estimated CLCR 120-180 mL/min), a prolonged 4 h infusion of standard dose is required.

CONCLUSIONS

The suggested dosing regimens will result in exposures of cefepime and tazobactam that would be adequate for infections caused by ESBL-producing pathogens with a cefepime/tazobactam MICs up to 16 mg/L.

Effect modification of dosing strategy (AUC or trough) on AKI associated with vancomycin in combination with piperacillin/tazobactam or cefepime and meropenem

Piperacillin-tazobactam (TZP), cefepime (FEP), or meropenem (MEM) and vancomycin (VAN) are commonly used in combination for sepsis. Studies have shown an increased risk of acute kidney injury (AKI) with TZP and VAN compared to FEP or MEM. VAN guidelines recommend area under the curve (AUC) monitoring over trough (Tr) to minimize the risk of AKI. We investigated the association of AKI and MAKE-30 with the two VAN monitoring strategies when used in combination with TZP or FEP/MEM. Adult patients between 2015 and 2019 with VAN > 72 hours were included. Patients with AKI prior to or within 48 hours of VAN or baseline CrCl of ≤30 mL/min were excluded. Four cohorts were defined: FEP/MEM/Tr, FEP/MEM/AUC, TZP/Tr, and TZP/AUC. A Cox Proportional Hazard Model was used to model AKI as a function of the incidence rate of at-risk days, testing monitoring strategy as a treatment effect modification. Multivariable logistic regression was used to model MAKE-30. Overall incidence of AKI was 18.6%; FEP/MEM/Tr = 115 (14.6%), FEP/MEM/AUC = 52 (14.9%), TZP/Tr = 189 (26%), and TZP/AUC = 96 (17.1%) (P < 0.001). Both drug group [(TZP; P = 0.0085)] and monitoring strategy [(Tr; P = 0.0007)] were highly associated with the development of AKI; however, the effect was not modified with interaction term [(TZP*Tr); 0.085)]. The odds of developing MAKE-30 were not different between any group and FEP/MEM/AUC. The effect of VAN/TZP on the development of AKI was not modified by the VAN monitoring strategy (AUC vs trough). MAKE-30 outcomes were not different among the four cohorts.

Risk and Time-to-Onset of Acute Kidney Injury With Vancomycin Plus Piperacillin-tazobactam Combination: Analysis Using JADER

BACKGROUND/AIM

Pharmacovigilance data and clinical studies have indicated a risk of acute kidney injury (AKI) associated with concomitant administration of vancomycin and piperacillin-tazobactam. However, no pharmacovigilance studies have evaluated time-to-onset and outcomes of AKI related to this combination. Therefore, this study used a pharmacovigilance database to investigate the incidence, time-to-onset, and outcomes of AKI in patients treated with intravenous vancomycin plus piperacillin-tazobactam or other antipseudomonal antibiotics.

PATIENTS AND METHODS

From data in the Japanese Adverse Drug Event Report (JADER) database, we calculated the reporting odds ratios (RORs) and 95% confidence intervals (CIs), time-to-onset, and outcomes of AKI following intravenous administration of vancomycin plus piperacillin-tazobactam or other antipseudomonal antibiotics and with other vancomycin regimens, including monotherapy.

RESULTS

The JADER database contained 4,471 reports of intravenous vancomycin treatment, including 517 reports of AKI. The adjusted RORs (95%CIs) of AKI in cases with co-administration of intravenous vancomycin and piperacillin-tazobactam was 2.58 (2.06-3.24). The median time-to-onset for AKI in vancomycin plus piperacillin-tazobactam was 6.0 (interquartile range=3.0-10.3). Weibull shape parameter analysis showed that the pattern of onset of AKI in vancomycin plus piperacillin-tazobactam represented a wear out failure, predicting an increasing hazard with time. For the outcome of AKI, there was no significant difference between all vancomycin regimen and the piperacillin-tazobactam combination groups.

CONCLUSION

Concomitant use of intravenous vancomycin and piperacillin-tazobactam may increase the incidence of AKI but may not affect the outcome. This combination does not necessarily have to be avoided, but long-term use is not advisable.

Effect of Cefepime/Enmetazobactam vs Piperacillin/Tazobactam on Clinical Cure and Microbiological Eradication in Patients With Complicated Urinary Tract Infection or Acute Pyelonephritis: A Randomized Clinical Trial

IMPORTANCE

Cefepime/enmetazobactam is a novel β-lactam/β-lactamase inhibitor combination and a potential empirical therapy for resistant gram-negative infections.

OBJECTIVE

To evaluate whether cefepime/enmetazobactam was noninferior to piperacillin/tazobactam for the primary outcome of treatment efficacy in patients with complicated urinary tract infections (UTIs) or acute pyelonephritis.

DESIGN, SETTING, AND PARTICIPANTS

A phase 3, randomized, double-blind, active-controlled, multicenter, noninferiority clinical trial conducted at 90 sites in Europe, North and Central America, South America, and South Africa. Recruitment occurred between September 24, 2018, and November 2, 2019. Final follow-up occurred November 26, 2019. Participants were adult patients aged 18 years or older with a clinical diagnosis of complicated UTI or acute pyelonephritis caused by gram-negative urinary pathogens.

INTERVENTIONS

Eligible patients were randomized to receive either cefepime, 2 g/enmetazobactam, 0.5 g (n = 520), or piperacillin, 4 g/tazobactam, 0.5 g (n = 521), by 2-hour infusion every 8 hours for 7 days (up to 14 days in patients with a positive blood culture at baseline).

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of patients in the primary analysis set (patients who received any amount of study drug with a baseline gram-negative pathogen not resistant to either treatment and ≥105 colony-forming units [CFU]/mL in urine culture or the same pathogen present in concurrent blood and urine cultures) who achieved overall treatment success (defined as clinical cure combined with microbiological eradication [<103 CFU/mL in urine] of infection). Two-sided 95% CIs were computed using the stratified Newcombe method. The prespecified noninferiority margin was -10%. If noninferiority was established, a superiority comparison was also prespecified.

RESULTS

Among 1041 patients randomized (mean age, 54.7 years; 573 women [55.0%]), 1034 (99.3%) received study drug and 995 (95.6%) completed the trial. Among the primary analysis set, the primary outcome occurred in 79.1% (273/345) of patients receiving cefepime/enmetazobactam compared with 58.9% (196/333) receiving piperacillin/tazobactam (between-group difference, 21.2% [95% CI, 14.3% to 27.9%]). Treatment-emergent adverse events occurred in 50.0% (258/516) of patients treated with cefepime/enmetazobactam and 44.0% (228/518) with piperacillin/tazobactam; most were mild to moderate in severity (89.9% vs 88.6%, respectively). A total of 1.7% (9/516) of participants who received cefepime/enmetazobactam and 0.8% (4/518) of those who received piperacillin/tazobactam did not complete the assigned therapy due to adverse events.

CONCLUSIONS AND RELEVANCE

Among patients with complicated UTI or acute pyelonephritis caused by gram-negative pathogens, cefepime/enmetazobactam, compared with piperacillin/tazobactam, met criteria for noninferiority as well as superiority with respect to the primary outcome of clinical cure and microbiological eradication. Further research is needed to determine the potential role for cefepime/enmetazobactam in the treatment of complicated UTI and pyelonephritis.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03687255.

Bloodstream Infections in Children With Cancer: Pathogen Distribution and Antimicrobial Susceptibility Patterns Over a 10-Year Period

Bloodstream infections (BSIs) adversely affect clinical outcome in children with cancer. Over 1 decade, this retrospective cohort study describes pathogen distribution in BSIs and antimicrobial susceptibility against empirical antibiotics frequently prescribed in children with cancer. The antibiotic efficacy was evaluated through the determination of minimal inhibitory concentrations for piperacillin-tazobactam and meropenem and by disk diffusion for remaining antibiotics. From 2004 to 2013, 398 BSIs occurred in 196 children with cancer (median age: 5.4 y), resulting in 457 bacteria. Overall, 266 (58.2%) were Gram-positive, and 191 (41.8%) were Gram-negative with a significant Gram-positive increase over time (P=0.032). Coagulase-negative staphylococci (74, 16.2%), viridans group streptococci (67, 14.7%), Escherichia coli (52, 11.4%), and Staphylococcus aureus (39, 8.5%) were the most common pathogens. Susceptibility to piperacillin-tazobactam (95.9%, P=0.419) and meropenem (98.9%, P=0.752) was stable over time, and resistance was observed among viridans group streptococci against piperacillin-tazobactam (18%) and meropenem (7%) and among Enterobacterales against piperacillin-tazobactam (3%). Vancomycin showed 98% Gram-positive activity, gentamicin 82% Gram-negative activity and ampicillin, cefotaxime, and cefuroxime were active in 50%, 72%, and 69% of pathogens, respectively, and BSI-related mortality was 0%. In conclusion, over 1 decade, we report an increase in Gram-positive BSIs, and stable, low-resistance rates against currently recommended empirical antibiotics, piperacillin-tazobactam and meropenem.

Lowered Risk of Nephrotoxicity through Intervention against the Combined Use of Vancomycin and Tazobactam/Piperacillin: A Retrospective Cohort Study

The combined use of vancomycin (VCM) and tazobactam/piperacillin (TAZ/PIPC) is a major risk factor for nephrotoxicity. We sought to evaluate interventions against the combined use of VCM and TAZ/PIPC. This retrospective cohort study involved patients who considered the combined use of VCM and TAZ/PIPC as a treatment. Patients that had either or both antimicrobials replaced were assigned to the intervention group, whereas those who were continued on combination therapy were assigned to the comparison group. The primary endpoint was the incidence of acute kidney injury (AKI). The survival rate of patients on day 30 was evaluated as the secondary endpoint. The comparison and intervention groups were composed of 65 and 68 patients, respectively, and the incidence rates of AKI were 44.6% and 17.6%, respectively. Cox proportional hazard analysis identified the intervention as the only independent factor against AKI development, with a hazard ratio of 0.282 (95% confidence interval [CI], 0.141 to 0.565). For the incidence of AKI of grade greater than 1, the hazard ratio was 0.114 (95% CI, 0.025 to 0.497). The survival rates on day 30 in the comparison and intervention groups were 92.3% and 91.2%, respectively, with a relative risk of 0.988 (95% CI, 0.892 to 1.094). The trough VCM concentration was not associated with the incidence of AKI in patients receiving the combination therapy. This study demonstrated that intervention against the combined use of VCM and TAZ/PIPC can lower the risk of nephrotoxicity. IMPORTANCE The combined use of vancomycin (VCM) and tazobactam/piperacillin (TAZ/PIPC) is a major risk factor for nephrotoxicity. We retrospectively evaluated interventions against the combined use of VCM and TAZ/PIPC. Patients for whom either or both antimicrobials were replaced were assigned to the intervention group (65 patients), whereas those who were continued on combination therapy were assigned to the comparison group (68 patients). The primary endpoint was the incidence of acute kidney injury (AKI). The incidence rates of AKI in the intervention and comparison groups were 44.6% and 17.6%, respectively. Cox proportional hazard analysis identified intervention as the only independent factor against AKI development, with a hazard ratio of 0.282 (95% confidence interval [CI], 0.141 to 0.565). In conclusion, this study demonstrated that intervention against the combined use of VCM and TAZ/PIPC can lower the risk of nephrotoxicity.

Acute Cholecystitis, Sepsis, and Disseminated Intravascular Coagulation Caused by Edwardsiella tarda in an Elderly Woman

Edwardsiella tarda is a gram-negative bacillus associated with gastrointestinal diseases. It is rarely responsible for sepsis; however, the fatality is very high. Only two cases of E. tarda infections in patients over 90 years of age have been reported; these are not cases of sepsis associated with acute cholecystitis. We report a case of acute cholecystitis, sepsis, and disseminated intravascular coagulation (DIC) caused by E. tarda in a super-elderly woman aged over 90 years. There could be a possibility for recovery from sepsis and DIC if antimicrobial treatment responsiveness is ensured in the super-elderly.

A NSQIP-based randomized clinical trial evaluating choice of prophylactic antibiotics for pancreaticoduodenectomy

Surgical site infection after pancreaticoduodenectomy is often caused by pathogens resistant to standard prophylactic antibiotics, suggesting that broad-spectrum antibiotics may be more effective prophylactic agents. This article describes the rationale and methodology underlying a multicenter randomized trial evaluating piperacillin-tazobactam compared with cefoxitin for surgical site infection prevention following pancreaticoduodenectomy. As the first US randomized surgical trial to utilize a clinical registry for data collection, this study serves as proof of concept for registry-based clinical trials.

Nephrotoxicity from Vancomycin Combined with Piperacillin-Tazobactam: A Comprehensive Review

BACKGROUND

Recent studies have identified the combination of vancomycin with piperacillin-tazobactam (VPT) to be associated with increased nephrotoxicity. Multiple, large cohort studies have found this widely used combination to have a higher risk of nephrotoxicity than other regimens in a variety of populations.

SUMMARY

This review summarizes the epidemiology and clinical features of VPT-associated acute kidney injury (AKI). Potential mechanisms involved in the pathogenesis of this phenomenon are also discussed. Key Message: VPT-associated nephrotoxicity is a recently recognized clinical entity. Clinical strategies to minimize the risk of toxicity in this setting include antimicrobial stewardship, monitoring of kidney function, and emerging data supporting the potential role for novel biomarkers in predicting and managing AKI.

Chromobacterium violaceum infection on lower limb skin: A case report

RATIONAL

Chromobacterium violaceum is a motile gram-negative bacterium. This bacterium commonly grows in tropical or subtropical areas in sewage and can cause opportunistic infections.

PATIENT CONCERNS

A 50-year-old Chinese man had a skin ulcer in the middle of his left leg in front of the tibia. The diameter of the wound was 3.0 cm, the exudation was obvious, and necrotic tissue was attached to the wound. One week previously, he was working in a field where he accidentally punctured his left leg.

DIAGNOSIS

C violaceum infection was diagnosed as per the results of pathogen culture from the infection site.

INTERVENTIONS

He was treated with piperacillin/tazobactam (3.375 g/12 h iv) and levofloxacin (0.5 g/24 h iv) for 5 days.

OUTCOMES

The patient showed good response to therapy and was discharged on day 18 after wound healing.

LESSONS

C violaceum rarely infects humans. When an infection is suspected, samples should be immediately sent for microbial culture. Timely treatment on the basis of drug sensitivity test results can prevent further complications.

Incidence of Nephrotoxicity Among Pediatric Patients Receiving Vancomycin With Either Piperacillin-Tazobactam or Cefepime: A Cohort Study

BACKGROUND

Recent studies in adults have found an incidence of acute kidney injury (AKI) in patients treated with a combination of vancomycin and piperacillin-tazobactam (TZP) that is greater than that expected with either medication alone. The purpose of this study was to determine whether combination therapy with vancomycin and TZP is associated with an incidence of AKI in pediatric patients higher than that in those on combination therapy with vancomycin and cefepime.

METHODS

We performed a retrospective single-center matched-cohort study of pediatric patients who received vancomycin in combination with TZP or cefepime between January 2015 and June 2016. The patients were matched according to chronic disease, age, sex, and number of concomitant nephrotoxic medications at the time of combination antibiotic therapy. The primary outcome was incidence of AKI. Secondary outcomes included differences between groups in time to AKI, resolution of AKI, and effect of vancomycin trough levels on the incidence of nephrotoxicity. Conditional logistic regression was used to compare categorical and continuous variables between treatment groups. Conditional Poisson regression was used to assess the association between AKI and treatment groups. Stratified log-rank tests and Cox proportional hazards models with shared frailty were used to compare the times to AKI according to treatment group.

RESULTS

Two hundred twenty-eight matched patients were included. AKI developed in 9 (7.9%) of 114 and 33 (28.9%) of 114 patients in the cefepime and TZP groups, respectively (P < .001). Type of combination therapy remained a significant predictor for AKI in multivariate conditional Poisson analysis in which adjustments were made for age, sex, use of concomitant nephrotoxins, and vancomycin dose (relative risk, 2.5 [95% confidence interval, 1.1-5.8]; P = .03). AKI developed almost 3 times sooner in the TZP group than in the cefepime group (hazard ratio, 2.9 [95% confidence interval, 1.3-6.1]; P = .006). Sensitivity analyses in which adjustment was made for antibiotic indication in addition to the aforementioned variables and excluding those with gastrointestinal infection revealed similar results.

CONCLUSION

Among hospitalized children at our institution, combination therapy with vancomycin and TZP was associated with an incidence of AKI higher than that associated with vancomycin and cefepime.

A protocol for a phase 3 multicentre randomised controlled trial of continuous versus intermittent β-lactam antibiotic infusion in critically ill patients with sepsis: BLING III

BACKGROUND AND RATIONALE

β-Lactam antibiotics display a time-dependent mechanism of action, with evidence suggesting improved outcomes when administering these drugs via continuous infusion compared with standard intermittent infusion. However, there is no phase 3 randomised controlled trial (RCT) evidence to support one method of administration over another in critically ill patients with sepsis.

DESIGN AND SETTING

The β-Lactam Infusion Group (BLING) III study is a prospective, multicentre, open, phase 3 RCT to compare continuous infusion with standard intermittent infusion of β-lactam antibiotics in critically ill patients with sepsis. The study will be conducted in about 70 intensive care units (ICUs) in Australia, New Zealand, the United Kingdom, Belgium and selected other countries, from 2018 to 2021.

PARTICIPANTS AND INTERVENTIONS

BLING III will recruit 7000 critically ill patients with sepsis being treated with one of two β-lactam antibiotics (piperacillin-tazobactam or meropenem) to receive the β-lactam antibiotic by either continuous or intermittent infusion.

MAIN OUTCOME MEASURES

The primary outcome is allcause mortality within 90 days after randomisation. Secondary outcomes are clinical cure at Day 14 after randomisation, new acquisition, colonisation or infection with a multiresistant organism or Clostridium difficile diarrhoea up to 14 days after randomisation, all-cause ICU mortality and all-cause hospital mortality. Tertiary outcomes are ICU length of stay, hospital length of stay and duration of mechanical ventilation and duration of renal replacement therapy up to 90 days after randomisation.

RESULTS AND CONCLUSIONS

The BLING III study will compare the effect on 90-day mortality of β-lactam antibiotics administered via continuous versus intermittent infusion in 7000 critically ill patients with sepsis.

TRIAL REGISTRATION

ClinicalTrials.gov Registry (NCT03213990).