Safety and tolerability of high-dose weekly liposomal amphotericin B antifungal prophylaxis

Efficacy and safety of posaconazole and liposomal amphotericin B use for prophylaxis of invasive fungal infections in a paediatric and young adult haemato-oncological population

BACKGROUND

The prevention of invasive fungal infections (IFIs) is crucial for paediatric haemato-oncological patients. This study evaluates the clinical efficacy and side-effects of posaconazole and liposomal amphotericin B (L-AmB) as primary prophylaxis.

MATERIALS AND METHODS

This cohort study included patients aged 3 months to 21 years who received posaconazole or L-AmB (5 mg/kg twice weekly) as prophylaxis from January 2017 to March 2022 at the Hemato-oncological Pediatric Unit, University Hospital of Padua, Italy. Outcomes included adverse events and IFI diagnoses after the start of prophylaxis. Separate analyses were performed for patients with ALL and non-ALL diagnoses, and high-risk and low-risk groups. Cumulative incidence was calculated using the Kaplan-Meier estimator, with significant differences assessed using the log-rank test. Hazard ratios (HR) were estimated using Cox regression.

RESULTS

Fifty-one patients received posaconazole, and 37 received L-AmB. Adverse events occurred in 26% of L-AmB patients and 5.6% of posaconazole patients. IFI breakthrough events were similar in both groups (four events each). In ALL patients, 41% experienced adverse events with L-AmB, compared to 5% with posaconazole. After 1 year, the probability of adverse events was lower in the posaconazole group (54% versus 65%, P < 0.001). Overall, posaconazole was associated with a 91% lower risk of adverse events (HR: 0.07, P < 0.001). Among high-risk patients, IFI breakthrough rates were similar between groups (P = 0.964).

CONCLUSIONS

Posaconazole was associated with fewer adverse events than L-AmB, and both drugs showed similar efficacy in preventing IFI breakthroughs, making posaconazole a viable alternative for primary prophylaxis.

Mold-Active Antifungal Prophylaxis in Pediatric Patients with Cancer or Undergoing Hematopoietic Cell Transplantation

Invasive fungal diseases (IFDs), in particular invasive mold infections, still pose considerable problems in the care of children and adolescents treated for cancer or undergoing hematopoietic cell transplantation. As these infections are difficult to diagnose, and the outcomes for IFDs are still unsatisfactory, antifungal prophylaxis has become an important strategy in the clinical setting. Antifungal prophylaxis is indicated in patients at high risk for IFD, which is commonly defined as a natural incidence of at least 10%. As there is a growing interest in pediatric-specific clinical trials and pediatric-specific guidelines, this review focuses on the available data of mold-active antifungal prophylaxis in children and adolescents. The data demonstrate that a major effort is needed to characterize the pediatric patient population in which the net effect of prophylactic antifungals will be beneficial as well as to find the optimal prophylactic antifungal compound and dosage.

Pediatric Antifungal Prescribing Patterns Identify Significant Opportunities to Rationalize Antifungal Use in Children

OBJECTIVE

The need for pediatric antifungal stewardship programs has been driven by an increasing consumption of antifungals for prophylactic and empirical use. Drivers and rational of antifungal prescribing need to be identified to optimize prescription behaviors.

METHODS

A prospective modified weekly Point Prevalence Survey capturing antifungal prescriptions for children (> 90 days to < 18 years of age) in 12 centers in England during 26 consecutive weeks was performed. Demographic, diagnostic and treatment information was collected for each patient. Data were entered into an online REDCap database.

RESULTS

One thousand two hundred fifty-eight prescriptions were included for 656 pediatric patients, 44.9% were girls, with a median age of 6.4 years (interquartile range, 2.5-11.3). Most common underlying condition was malignancy (55.5%). Four hundred nineteen (63.9%) received antifungals for prophylaxis, and 237 (36.1%) for treatment. Among patients receiving antifungal prophylaxis, 40.2% did not belong to a high-risk group. In those receiving antifungal treatment, 45.9%, 29.4%, 5.1% and 19.6% had a diagnosis of suspected, possible, probable of proven invasive fungal disease (IFD), respectively. Proven IFD was diagnosed in 78 patients, 84.6% (n = 66) suffered from invasive candidiasis and 15.4% (n = 12) from an invasive mold infection. Liposomal amphotericin B was the most commonly prescribed antifungal for both prophylaxis (36.6%) and empiric and preemptive treatment (47.9%). Throughout the duration of the study, 72 (11.0%) patients received combination antifungal therapy.

CONCLUSIONS

Antifungal use in pediatric patients is dominated by liposomal amphotericin B and often without evidence for the presence of IFD. A significant proportion of prophylactic and empiric antifungal use was seen in pediatric patients not at high-risk for IFD.

Consensus guidelines for antifungal prophylaxis in haematological malignancy and haemopoietic stem cell transplantation, 2021

Antifungal prophylaxis can reduce morbidity and mortality from invasive fungal disease (IFD). However, its use needs to be optimised and appropriately targeted to patients at highest risk to derive the most benefit. In addition to established risks for IFD, considerable recent progress in the treatment of malignancies has resulted in the development of new 'at-risk' groups. The changing epidemiology of IFD and emergence of drug resistance continue to impact choice of prophylaxis, highlighting the importance of active surveillance and knowledge of local epidemiology. These guidelines aim to highlight emerging risk groups and review the evidence and limitations around new formulations of established agents and new antifungal drugs. It provides recommendations around use and choice of antifungal prophylaxis, discusses the potential impact of the changing epidemiology of IFD and emergence of drug resistance, and future directions for risk stratification to assist optimal management of highly vulnerable patients.

Case reports of invasive mucormycosis associated neutropenic enterocolitis in leukemic children: diagnostic and treatment challenges and review of literature

Background

Bacterial enterocolitis is one of the most common neutropenic fever complications during intensive chemotherapy. Despite aggressive antibacterial treatments, this complication usually imposes high morbidity and mortality in cancer patients. Management of bacterial neutropenic enterocolitis are well known; however, management of fungal neutropenic enterocolitis may be more challenging and needs to be investigated. Prompt diagnosis and treatment may be life-saving, especially in patients at risk of mucormycosis-associated neutropenic enterocolitis.

Case presentation

We report two mucormycosis-associated neutropenic enterocolitis cases in pediatric leukemic patients receiving salvage chemotherapy for disease relapse. Both patients' clinical signs and symptoms differ from classical bacterial neutropenic enterocolitis. They were empirically treated as bacterial neutropenic enterocolitis with anti-gram-negative combination therapy. Despite broad-spectrum antimicrobial treatment, no clinical improvement was achieved, and both of them were complicated with severe abdominal pain necessitating surgical intervention. Mucormycosis is diagnosed by immunohistopathologic examination in multiple intraoperative intestinal tissue biopsies. Both patients died despite antifungal treatment with liposomal amphotericin-B and surgical intervention.

Conclusion

Mucormycosis-associated neutropenic enterocolitis is one of the most unfavorable and untreatable side effects of salvage chemotherapy in leukemic children with disease relapse. This report could be of considerable insight to the clinicians and scientists who counter the enigma of fungal infections during febrile neutropenia and help to understand better diagnosis and management.

Low-dose liposomal amphotericin B for antifungal prophylaxis in paediatric allogeneic haematopoietic stem cell transplantation

BACKGROUND

Primary antifungal prophylaxis in paediatric allogeneic HSCT recipients is mainly based on azoles, which can have related toxicity and drug interactions. Low-dose liposomal amphotericin B (L-AmB) is an attractive intravenous alternative because of its low toxicity and lower risk of interactions.

OBJECTIVES

To evaluate the effectiveness and safety of L-AmB (1 mg/kg/day) for primary antifungal prophylaxis in pre-engraftment paediatric HSCT patients.

PATIENTS AND METHODS

Retrospective, observational study including all consecutive patients aged ≤18 years who underwent HSCT and received antifungal prophylaxis with intravenous L-AmB (1 mg/kg/day, from day -1 to 48 h before discharge) between January 2012 and December 2016.

RESULTS

In total, 125 HSCT procedures in 118 patients were included, median age 7.2 years (IQR 4.2-11.5). Haematological malignancies were the main underlying condition (63.6%), and 109 (87.2%) were considered at high risk for invasive fungal infection (IFI). Ten patients (7.7%), all high risk, developed breakthrough IFI (three Candida spp., seven invasive mould infections) and tended to have higher overall mortality. The only statistically significant risk factor for IFI was cytomegalovirus co-infection. Adverse events, all grade I, occurred in 25 (20%), requiring L-AmB withdrawal in one case. Overall survival at 30 days was 99.2%. At study completion, one patient had died of IFI.

CONCLUSIONS

The incidence of breakthrough IFI was comparable to that of previous reports, with a very low rate of significant toxicity. Thus, prophylactic L-AmB may be a safe, effective option for antifungal prophylaxis in the pre-engraftment phase for children undergoing HSCT, even those at high risk.

Safety and Efficacy of Intermittent High-Dose Liposomal Amphotericin B Antifungal Prophylaxis in Haemato-Oncology: An Eight-Year Single-Centre Experience and Review of the Literature

Triazoles remain first-line agents for antifungal prophylaxis in high-risk haemato-oncology patients, but their use is increasingly contraindicated due to drug–drug interactions and additive toxicities with novel treatments. In this retrospective, single-centre, observational study, we present our eight-year experience of antifungal prophylaxis using intermittent high-dose liposomal Amphotericin B (L-AmB). All adults identified through our Antifungal Stewardship Programme as receiving L-AmB prophylaxis at 7.5 mg/kg once-weekly between February 2012 and January 2020 were included. Adverse reactions, including infusion reactions, electrolyte loss, and nephrotoxicity, were recorded. ‘Breakthrough’ invasive fungal infection (IFI) occurring within four weeks of L-AmB was classified using European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) criteria. Moreover, 114 courses of intermittent high-dose L-AmB prophylaxis administered to 92 unique patients were analysed. Hypokalaemia was the most common grade 3–4 adverse event, with 26 (23%) courses. Grade 3 nephrotoxicity occurred in 8 (7%) and reversed in all six patients surviving to 90 days. There were two (1.8%) episodes of breakthrough IFI, one ‘probable’ and one ‘possible’. In this study, the largest evaluation of intermittent high-dose L-AmB prophylaxis conducted to date, toxicity was manageable and reversible and breakthrough IFI was rare. L-AmB prophylaxis represents a viable alternative for patients with a contraindication to triazoles.

ESCMID-ECMM guideline: diagnosis and management of invasive aspergillosis in neonates and children

SCOPE

Presenting symptoms, distributions and patterns of diseases and vulnerability to invasive aspergillosis (IA) are similar between children and adults. However, differences exist in the epidemiology and underlying conditions, the usefulness of newer diagnostic tools, the pharmacology of antifungal agents and in the evidence from interventional phase 3 clinical trials. Therefore, the European Society for Clinical Microbiology and Infectious Diseases (ESCMID) and the European Confederation of Medical Mycology (ECMM) have developed a paediatric-specific guideline for the diagnosis and management of IA in neonates and children.

METHODS

Review and discussion of the scientific literature and grading of the available quality of evidence was performed by the paediatric subgroup of the ESCMID-ECMM-European Respiratory Society (ERS) Aspergillus disease guideline working group, which was assigned the mandate for the development of neonatal- and paediatric-specific recommendations.

QUESTIONS

Questions addressed by the guideline included the epidemiology of IA in neonates and children; which paediatric patients may benefit from antifungal prophylaxis; how to diagnose IA in neonates and children; which antifungal agents are available for use in neonates and children; which antifungal agents are suitable for prophylaxis and treatment of IA in neonates and children; what is the role of therapeutic drug monitoring of azole antifungals; and which management strategies are suitable to be used in paediatric patients. This guideline provides recommendations for the diagnosis, prevention and treatment of IA in the paediatric population, including neonates. The aim of this guideline is to facilitate optimal management of neonates and children at risk for or diagnosed with IA.

Invasive Fungal Infections While on Voriconazole, Liposomal Amphotericin B, or Micafungin for Antifungal Prophylaxis in Pediatric Stem Cell Transplant Patients

OBJECTIVE

This study aimed to report the incidence of invasive fungal infections (IFIs) in pediatric hematopoietic stem cell transplant (HSCT) patients who received voriconazole, liposomal amphotericin B (L-AMB), or micafungin for primary antifungal prophylaxis (PAP).

METHODS

Using data retrospectively collected from institution's electronic records, this study analyzed the incidence of IFIs in pediatric HSCT patients between November 2012 and November 2016.

RESULTS

A total of 103 patients were screened. Of the 84 patients who met inclusion criteria, 76.2%, 29.8%, and 19% patients received voriconazole, L-AMB, and micafungin, respectively. The incidence of overall IFIs was 2.08 per 1000 prophylaxis days. There were 2 mold infections identified in 2 patients. Among 3 antifungal agents, the rates of IFIs were 2.67 per 1000 prophylaxis days in L-AMB group, 2.08 per 1000 prophylaxis days in micafungin group, and 1.17 per 1000 prophylaxis days in voriconazole group.

CONCLUSION

Patients who received L-AMB or micafungin had higher rates of IFIs than those who received voriconazole for PAP.

Safety, Tolerability, and Pharmacokinetics of Liposomal Amphotericin B in Immunocompromised Pediatric Patients

The safety, tolerability, and pharmacokinetics of the liposomal formulation of amphotericin B (L-AMB) were evaluated in 40 immunocompromised children and adolescents. The protocol was an open-label, sequential-dose-escalation, multidose pharmacokinetic study with 10 to 13 patients in each of the four dosage cohorts. Each cohort received daily dosages of 2.5, 5.0, 7.5, or 10 mg of amphotericin B in the form of L-AMB per kg of body weight. Neutropenic patients between the ages of 1 and 17 years were enrolled to receive empirical antifungal therapy or treatment of documented invasive fungal infections. The pharmacokinetic parameters of L-AMB were measured as those of amphotericin B by high-performance liquid chromatography and calculated by noncompartmental methods. There were nine adverse-event-related discontinuations, four of which were related to infusions. Infusion-related side effects occurred for 63 (11%) of 565 infusions, with 5 patients experiencing acute infusion-related reactions (7.5- and 10-mg/kg dosage levels). Serum creatinine levels increased from 0.45 ± 0.04 mg/dl to 0.63 ± 0.06 mg/dl in the overall population (P = 0.003), with significant increases in dosage cohorts receiving 5.0 and 10 mg/kg/day. At the higher dosage level of 10 mg/kg, there was a trend toward greater hypokalemia and vomiting. The area under the concentration-time curve from 0 to 24 h (AUC_0-24) values for L-AMB on day 1 increased from 54.7 ± 32.9 to 430 ± 566 μg · h/ml in patients receiving 2.5 and 10.0 mg/kg/day, respectively. These findings demonstrate that L-AMB can be administered to pediatric patients at dosages similar to those for adults and that azotemia may develop, especially in those receiving ≥5.0 mg/kg/day.

Fungal diseases: could nanostructured drug delivery systems be a novel paradigm for therapy?

Invasive mycoses are a major problem for immunocompromised individuals and patients in intensive care units. Morbidity and mortality rates of these infections are high because of late diagnosis and delayed treatment. Moreover, the number of available antifungal agents is low, and there are problems with toxicity and resistance. Alternatives for treating invasive fungal infections are necessary. Nanostructured systems could be excellent carriers for antifungal drugs, reducing toxicity and targeting their action. The use of nanostructured systems for antifungal therapy began in the 1990s, with the appearance of lipid formulations of amphotericin B. This review encompasses different antifungal drug delivery systems, such as liposomes, carriers based on solid lipids and nanostructure lipids, polymeric nanoparticles, dendrimers, and others. All these delivery systems have advantages and disadvantages. Main advantages are the improvement in the antifungal properties, such as bioavailability, reduction in toxicity, and target tissue, which facilitates innovative therapeutic techniques. Conversely, a major disadvantage is the high cost of production. In the near future, the use of nanosystems for drug delivery strategies can be used for delivering peptides, including mucoadhesive systems for the treatment of oral and vaginal candidiasis.