Evaluation of anidulafungin in the treatment of intra-abdominal candidiasis: a pooled analysis of patient-level data from 5 prospective studies

The Surgical Infection Society Guidelines on the Management of Intra-Abdominal Infection: 2024 Update

Background: The Surgical Infection Society (SIS) published evidence-based guidelines for the management of intra-abdominal infection (IAI) in 1992, 2002, 2010, and 2017. Here, we present the most recent guideline update based on a systematic review of current literature. Methods: The writing group, including current and former members of the SIS Therapeutics and Guidelines Committee and other individuals with content or guideline expertise within the SIS, working with a professional librarian, performed a systematic review using PubMed/Medline, the Cochrane Library, Embase, and Web of Science from 2016 until February 2024. Keyword descriptors combined "surgical site infections" or "intra-abdominal infections" in adults limited to randomized controlled trials, systematic reviews, and meta-analyses. Additional relevant publications not in the initial search but identified during literature review were included. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) system was utilized to evaluate the evidence. The strength of each recommendation was rated strong (1) or weak (2). The quality of the evidence was rated high (A), moderate (B), or weak (C). The guideline contains new recommendations and updates to recommendations from previous IAI guideline versions. Final recommendations were developed by an iterative process. All writing group members voted to accept or reject each recommendation. Results: This updated evidence-based guideline contains recommendations from the SIS for the treatment of adult patients with IAI. Evidence-based recommendations were developed for antimicrobial agent selection, timing, route of administration, duration, and de-escalation; timing of source control; treatment of specific pathogens; treatment of specific intra-abdominal disease processes; and implementation of hospital-based antimicrobial agent stewardship programs. Summary: This document contains the most up-to-date recommendations from the SIS on the prevention and management of IAI in adult patients.

Echinocandins - structure, mechanism of action and use in antifungal therapy

With increasing number of immunocompromised patients as well as drug resistance in fungi, the risk of fatal fungal infections in humans increases as well. The action of echinocandins is based on the inhibition of β-(1,3)-d-glucan synthesis that builds the fungal cell wall. Caspofungin, micafungin, anidulafungin and rezafungin are semi-synthetic cyclic lipopeptides. Their specific chemical structure possess a potential to obtain novel derivatives with better pharmacological properties resulting in more effective treatment, especially in infections caused by Candida and Aspergillus species. In this review we summarise information about echinocandins with closer look on their chemical structure, mechanism of action, drug resistance and usage in clinical practice. We also introduce actual trends in modification of this antifungals as well as new methods of their administration, and additional use in viral and bacterial infections.

Risk Factors for Intra-Abdominal Candidiasis in Intensive Care Units: Results from EUCANDICU Study

INTRODUCTION

Intra-abdominal infections represent the second most frequently acquired infection in the intensive care unit (ICU), with mortality rates ranging from 20% to 50%. Candida spp. may be responsible for up to 10-30% of cases. This study assesses risk factors for development of intra-abdominal candidiasis (IAC) among patients admitted to ICU.

METHODS

We performed a case-control study in 26 European ICUs during the period January 2015-December 2016. Patients at least 18 years old who developed an episode of microbiologically documented IAC during their stay in the ICU (at least 48 h after admission) served as the case cohort. The control group consisted of adult patients who did not develop episodes of IAC during ICU admission. Matching was performed at a ratio of 1:1 according to time at risk (i.e. controls had to have at least the same length of ICU stay as their matched cases prior to IAC onset), ICU ward and period of study.

RESULTS

During the study period, 101 case patients with a diagnosis of IAC were included in the study. On univariate analysis, severe hepatic failure, prior receipt of antibiotics, prior receipt of parenteral nutrition, abdominal drain, prior bacterial infection, anastomotic leakage, recurrent gastrointestinal perforation, prior receipt of antifungal drugs and higher median number of abdominal surgical interventions were associated with IAC development. On multivariate analysis, recurrent gastrointestinal perforation (OR 13.90; 95% CI 2.65-72.82, p = 0.002), anastomotic leakage (OR 6.61; 95% CI 1.98-21.99, p = 0.002), abdominal drain (OR 6.58; 95% CI 1.73-25.06, p = 0.006), prior receipt of antifungal drugs (OR 4.26; 95% CI 1.04-17.46, p = 0.04) or antibiotics (OR 3.78; 95% CI 1.32-10.52, p = 0.01) were independently associated with IAC.

CONCLUSIONS

Gastrointestinal perforation, anastomotic leakage, abdominal drain and prior receipt of antifungals or antibiotics may help to identify critically ill patients with higher probability of developing IAC. Prospective studies are needed to identify which patients will benefit from early antifungal treatment.

Therapeutic Drug Monitoring of the Echinocandin Antifungal Agents: Is There a Role in Clinical Practice? A Position Statement of the Anti-Infective Drugs Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology

PURPOSE

Reduced exposure to echinocandins has been reported in specific patient populations, such as critically ill patients; however, fixed dosing strategies are still used. The present review examines the accumulated evidence supporting echinocandin therapeutic drug monitoring (TDM) and summarizes available assays and sampling strategies.

METHODS

A literature search was conducted using PubMed in December 2020, with search terms such as echinocandins, anidulafungin, caspofungin, micafungin, or rezafungin with pharmacology, pharmacokinetics (PKs), pharmacodynamics (PDs), drug-drug interactions, TDM, resistance, drug susceptibility testing, toxicity, adverse drug reactions, bioanalysis, chromatography, and mass spectrometry. Data on PD/PD (PK/PD) outcome markers, drug resistance, PK variability, drug-drug interactions, assays, and TDM sampling strategies were summarized.

RESULTS

Echinocandins demonstrate drug exposure-efficacy relationships, and maximum concentration/minimal inhibitory concentration ratio (Cmax/MIC) and area under the concentration-time curve/MIC ratio (AUC/MIC) are proposed PK/PD markers for clinical response. The relationship between drug exposure and toxicity remains poorly clarified. TDM could be valuable in patients at risk of low drug exposure, such as those with critical illness and/or obesity. TDM of echinocandins may also be useful in patients with moderate liver impairment, drug-drug interactions, hypoalbuminemia, and those undergoing extracorporeal membrane oxygenation, as these conditions are associated with altered exposure to caspofungin and/or micafungin. Assays are available to measure anidulafungin, micafungin, and caspofungin concentrations. A limited-sampling strategy for anidulafungin has been reported.

CONCLUSIONS

Echinocandin TDM should be considered in patients at known risk of suboptimal drug exposure. However, for implementing TDM, clinical validation of PK/PD targets is needed.

Candida glabrata Antifungal Resistance and Virulence Factors, a Perfect Pathogenic Combination

In recent years, a progressive increase in the incidence of invasive fungal infections (IFIs) caused by Candida glabrata has been observed. The objective of this literature review was to study the epidemiology, drug resistance, and virulence factors associated with the C. glabrata complex. For this purpose, a systematic review (January 2001-February 2021) was conducted on the PubMed, Scielo, and Cochrane search engines with the following terms: "C. glabrata complex (C. glabrata sensu stricto, C. nivariensis, C. bracarensis)" associated with "pathogenicity" or "epidemiology" or "antibiotics resistance" or "virulence factors" with language restrictions of English and Spanish. One hundred and ninety-nine articles were found during the search. Various mechanisms of drug resistance to azoles, polyenes, and echinocandins were found for the C. glabrata complex, depending on the geographical region. Among the mechanisms found are the overexpression of drug transporters, gene mutations that alter thermotolerance, the generation of hypervirulence due to increased adhesion factors, and modifications in vital enzymes that produce cell wall proteins that prevent the activity of drugs designed for its inhibition. In addition, it was observed that the C. glabrata complex has virulence factors such as the production of proteases, phospholipases, and hemolysins, and the formation of biofilms that allows the complex to evade the host immune response and generate fungal resistance. Because of this, the C. glabrata complex possesses a perfect pathogenetic combination for the invasion of the immunocompromised host.

Priorities in peritonitis

PURPOSE OF REVIEW

Timely and adequate management are the key priorities in the care of peritonitis. This review focuses on the cornerstones of the medical support: source control and antiinfective therapies.

RECENT FINDINGS

Peritonitis from community-acquired or healthcare-associated origins remains a frequent cause of admission to the ICU. Each minute counts for initiating the proper management. Late diagnosis and delayed medical care are associated to dramatically increased mortality rates. The diagnosis of peritonitis can be difficult in these ICU cases. The signs of organ failures are more relevant than biological surrogates. A delayed source control and a late anti-infective therapy are of critical importance. The quality of source control and medical management are other key elements of the prognosis. The conventional rules applied for sepsis are applicable for peritonitis, including hemodynamic support and anti-infective therapy. Growing proportions of multidrug resistant pathogens are reported from surgical samples, mainly related to Gram-negative bacteria. The increasing complexity in the care of these critically ill patients is a strong incentive for a multidisciplinary approach.

SUMMARY

Early clinical diagnosis, timely and adequate source control and antiinfective therapy are the essential pillars of the management of peritonitis in ICU patients.

Invasive Candidiasis in Patients with Solid Tumors Treated with Anidulafungin: A Post Hoc Analysis of Efficacy and Safety of Six Pooled Studies

Background

Solid tumors are a common predisposing factor for invasive candidiasis (IC) or candidemia due to IC.

Objectives

Post hoc analysis of patient-level efficacy and safety data from six studies of anidulafungin (with similar protocols/endpoints) in adults with IC/candidemia summarized by past or recent diagnosis of solid tumors.

Patients/methods

Patients received a single intravenous (IV) dose of anidulafungin 200 mg, followed by 100 mg once daily. After ≥ 5 to ≥ 10 days of IV treatment, switch to oral voriconazole/fluconazole was permitted in all but one study. Time of solid tumor diagnosis was defined as past, ≥ 6; and recent, < 6 months prior to study entry. Primary endpoint: global response of success (GRS) rate at the end of IV therapy (EOIVT). Secondary endpoints included the GRS rate at the end of all therapy (EOT), all-cause mortality, and safety.

Results

The GRS rate in the overall population was 73.4% at EOIVT and 65.5% at EOT. Past or recent solid tumor diagnosis did not affect GRS at EOIVT or EOT (past: 75.5% and 71.4%; recent: 72.2% and 62.2%, respectively). All-cause mortality was 14.4% on day 14 and 20.1% at day 28. Most treatment-emergent adverse events were mild/moderate in severity (81.6%).

Conclusions

Treatment of IC was effective regardless of the time of solid tumor diagnosis.

Trial Registration

Data were pooled from six studies: NCT00496197 (first posted on ClinicalTrials.gov on July 4, 2007); NCT00548262 (first posted on ClinicalTrials.gov on October 23, 2007); NCT00537329 (first posted on ClinicalTrials.gov on October 1, 2007); NCT00689338 (first posted on ClinicalTrials.gov on June 3, 2008); NCT00806351 (first posted on ClinicalTrials.gov on December 10, 2008); NCT00805740 (first posted on ClinicalTrials.gov on December 10, 2008).

Patients with solid tumor cancers (cancer of internal organs) have increased risk of fungal infections that can spread in the body through the blood. Infection with Candida species, known as invasive candidiasis (IC) (Candida invades the body in places normally free from germs) or candidemia (Candida infection in the blood), can cause severe illness and/or death. Anidulafungin is an antifungal drug recommended to treat IC/candidemia. This post hoc analysis looked at how effective and safe anidulafungin was in adult patients with IC/candidemia with ‘recent’ or ‘past’ history of solid tumors. The analysis included patients diagnosed with cancer less than 6 months before (recent history) or more than 6 months before (past history) they first received anidulafungin. Patients received anidulafungin by injection (intravenously [IV]) into the veins and, for continued treatment, were able to take a different antifungal drug orally. Of 539 patients from six studies, 139 had confirmed IC/candidemia and a history of solid tumors. Approximately 7 out of 10 (72%) patients were cured or no longer had signs of Candida infection at the end of IV anidulafungin treatment. Results were similar in patients with past or recent diagnosis of solid tumors. Treatment side effects reported in approximately 8 out of 10 (82%) patients were mild-to-moderate in severity. This analysis suggests anidulafungin was well tolerated and effective at treating IC/candidemia in patients with solid tumors, whether diagnosed recently or in the past.

Therapeutic Potential of Fosmanogepix (APX001) for Intra-abdominal Candidiasis: from Lesion Penetration to Efficacy in a Mouse Model

Intra-abdominal candidiasis (IAC) is one of the most common yet underappreciated forms of invasive candidiasis. IAC is difficult to treat, and therapeutic failure and drug-resistant breakthrough infections are common in some institutions despite the use of echinocandins as first-line agents. Fosmanogepix (FMGX, formerly APX001) is a first-in-class antifungal prodrug that can be administered both intravenously and orally. FMGX is currently in phase 2 clinical development for the treatment of life-threatening invasive fungal infections. To explore the pharmacological properties and therapeutic potential of FMGX for IAC, we evaluated both drug penetration and efficacy of the active moiety manogepix (MGX, formerly APX001A) in liver tissues in a clinically relevant IAC mouse model infected with Candida albicans Matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) and laser capture microdissection (LCM)-directed absolute drug quantitation were employed to evaluate drug penetration into liver abscess lesions both spatially and quantitatively. The partitioning of MGX into lesions occurred slowly after a single dose; however, robust accumulation in the lesion was achieved after 3 days of repeated dosing. Associated with this drug penetration pattern, reduction in fungal burden and clearance in the liver were observed in mice receiving the multiday FMGX regimen. In comparison, administration of micafungin resulted in marginal reduction in fungal burden at the end of 4 days of treatment. These results suggest that FMGX is a promising candidate for the treatment of IAC.

Pharmacokinetics of echinocandins in suspected candida peritonitis: A potential risk for resistance

INTRODUCTION

A possible increase in Candida resistance, especially in Candida glabrata, has been speculated according to poor diffusion of echinocandins to peritoneal fluid.

MATERIALS/METHODS

Peritoneal and serum concentrations of caspofungin, micafungin and anidulafungin were analysed in surgical patients with suspected candida peritonitis. After 4 days of starting therapy, serum and peritoneal samples (through peritoneal drainage) were obtained at baseline, 1, 6, 12 and 24 h of drug administration. Micafungin and anidulafungin concentrations were determined using high-performance liquid chromatography (HPLC/F), whereas caspofungin concentrations were established by bioassay.

RESULTS

Twenty-three critically ill patients with suspected abdominal fungal infection who were receiving an echinocandin were prospectively recruited. No specific criteria were applied to prescribe one specific echinocandin. No special clinical differences were observed among the three groups of patients. All were receiving antibiotic therapy, 80% required inotropic drugs, and fungal peritonitis was confirmed in 74% of them. The AUC_{0_24h} (mg × h/L) obtained in serum and peritoneal fluid were: 126.84 and 34.38, 98.52 and 18.83, and 66.9 and 8.78 for anidulafungin, micafungin and caspofungin, respectively. The median concentration in peritoneal fluid ranged from 0.66 to 1.82 μg/mL for anidulafungin, 0.68-0.88 μg/mL for micafungin and 0.21-0.46 μg/mL for caspofungin.

CONCLUSION

The results showed moderate penetration of echinocandins into the peritoneal fluid of these patients. These levels are below the threshold of resistance mutant selection published by other authors. This could justify a potential risk of resistance in patients with prolonged treatment with echinocandins and suboptimal control of abdominal infection.

Effects of CGA-N12 on the membrane structure of Candida tropicalis cells

The antimicrobial peptide CGA-N12 (NH2-ALQGAKERAHQQ-COOH) is an active peptide derived from chromogranin A (CGA) and consists of the 65th to 76th amino acids of the N-terminus. The results of our previous studies showed that CGA-N12 exerts anti-Candida activity by inducing apoptosis without destroying the integrity of cell membranes. In this study, the effect of CGA-N12 on the cell membrane structure of Candida tropicalis was investigated. CGA-N12 resulted in the dissipation of the membrane potential, the increase in membrane fluidity, and the outflow of potassium ions in C. tropicalis without significantly changing the ergosterol level. Fluorescence quenching was applied to evaluate the membrane channel characteristics induced by CGA-N12 through detection of the following: membrane permeability of hydrated Cl− (ϕ ≈ 0.66 nm) using the membrane-impermeable halogen anion-selective fluorescent dye lucigenin, passage of the membrane-impermeable dye carboxyfluorescein (CF) (ϕ ≈ 1 nm) through the membrane, and membrane permeation of H3O+ based on the membrane non-permeable pH-sensitive fluorescent dye 8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt (HPTS). In conclusion, CGA-N12 can induce the formation of non-selective ion channels &lt;1 nm in diameter in the membranes of C. tropicalis, resulting in the leakage of potassium ions, chloride ions, and protons, among others, leading to dissipation of the membrane potential. As a result, the fluidity of membranes is increased without destroying the synthesis of ergosterol is not affected.