Safety, tolerability, and pharmacokinetics of Micafungin (FK463) in febrile neutropenic pediatric patients

Recent advances and challenges in the treatment of invasive fungal infections

The frequency of invasive fungal infections (IFIs) has increased over the last decade with the rise in at-risk populations of patients. The morbidity and mortality of IFIs are high and management of these conditions is a great challenge. With the widespread adoption of antifungal prophylaxis, the epidemiology of invasive fungal pathogens has changed. Non-albicans Candida, non-fumigatus Aspergillus and moulds other than Aspergillus have become increasingly recognised causes of invasive diseases. These emerging fungi are characterised by resistance or lower susceptibility to standard antifungal agents. Invasive infections due to these previously rare fungi are therefore more difficult to treat. Recently developed antifungal agents provide the potential to improve management options and therapeutic outcomes of these infections. The availability of more potent and less toxic antifungal agents, such as second-generation triazoles and echinocandins, has led to considerable improvement in the treatment of IFIs. This article reviews the changing spectrum of invasive mycosis, the properties of recently developed antifungal agents and their role in the management of these infections.

Micafungin sodium, the second of the echinocandin class of antifungals: theory and practice

Micafungin is a new drug in the echinocandin class and is currently being investigated in Phase III clinical trials. Like other echinocandins, it inhibits 1,3-beta-D-glucan synthesis, thus achieving fungicidal activity against virtually all Candida spp., including those resistant to fluconazole, and fungistatic activity against Aspergillus spp. Micafungin sodium is available for intravenous administration only. It has a favorable safety and drug-drug interaction profile. Micafungin has been approved by the US FDA for treatment of esophageal candidiasis and for antifungal prophylaxis during the pre-engraftment phase in patients undergoing hematopoietic stem cell transplantation. Considering the competitive pricing as well as the good tolerability and efficacy, at present micafungin seems to be another choice for both of these indications. Current research has proven micafungin sodium to add a rational and effective option to the antifungal armamentarium, especially in esophageal candidiasis refractory to fluconazole treatment, in those intolerant to triazoles or in patients needing concomitant therapy interacting with triazoles. In addition to the current indications, recent uncontrolled clinical trials have demonstrated a marked success in the treatment of candidemia and invasive candidiasis. Results from in vitro studies, animal models, small clinical trials, as well as the obvious comparison with the more established caspofungin, hint at possible future indications such as invasive aspergillosis and empirical antifungal therapy. However, preclinical data on micafungin is inconsistent and published well-designed clinical studies are scarce. More controlled and sufficiently scaled trials are imperative in order to establish micafungin as a reliable and safe option in clinical practice.

Population pharmacokinetics of micafungin in pediatric patients and implications for antifungal dosing

The echinocandins potentially have an important role in treatment of infections caused by Candida spp. and Aspergillus spp. in immunocompromised children. However, there are no population pharmacokinetic models of the echinocandins for pediatric patients. The safety and descriptive pharmacokinetics of micafungin in children were recently reported. However, a population pharmacokinetic model in children is needed in order to accurately determine the dosage of micafungin that produces an equivalent magnitude of drug exposure to that observed in adults. In order to explore the effect of weight on micafungin pharmacokinetics, a standard two-compartment pharmacokinetic model, a linear model, and an allometric power model were developed. For all three models, the fit to the data was excellent, with comparable measures of precision and bias. However, the superior log-likelihood value of the allometric power model suggested that it best reflected the data and was therefore chosen for a more detailed analysis of the magnitude and pattern of drug exposure which develop following the administration of micafungin. The allometric power model suggested that clearance in smaller children is higher than that predicted on the basis of weight alone. Consequently, a degree of dosage increase is required in smaller children to ensure comparable levels of drug exposure to those observed in larger children and adults. The allometric power model developed in this study enables identification of pediatric dosage regimens of micafungin which, based upon Monte Carlo simulations, result in equivalent drug exposures to those observed in adults, for which antifungal efficacy has been established.

The echinocandin micafungin: a review of the pharmacology, spectrum of activity, clinical efficacy and safety

Micafungin is a relatively broad-spectrum antifungal agent available for clinical use in the US and Japan. By inhibiting the production of beta-1,3-glucan, an essential fungal cell wall component, micafungin has reduced toxicity to mammalian cells while maintaining potent antifungal activity against many pathogenic fungi including polyene- and azole-resistant isolates. Indeed, micafungin has been shown to be efficacious in the treatment of infections caused by Candida and Aspergillus species in clinical trials without the associated toxicities of amphotericin B formulations and drug interactions that occur with the azoles. In this review, the pharmacology, spectrum of activity, clinical efficacy and safety profile of micafungin are discussed.

Invasive candidiasis in pediatric intensive care patients: epidemiology, risk factors, management, and outcome

BACKGROUND

The incidence of candidemia in pediatric patients follows the same pattern of increase as in adults, but the rate of increase is greater. Pediatric patients in critical condition, particularly young infants, are especially vulnerable to invasive Candida infections (ICI), partly because of their age and severe underlying disease and partly because of the invasive procedures used.

DISCUSSION

Central venous catheters and arterial lines, parenteral nutrition, mechanical ventilation and extended use of antimicrobials enhance the risk of ICI. C. albicans continues to be the most prevalent isolate. However, an increasing role of non-C. albicans (NAC) spp., some of which are intrinsically or potentially resistant to antifungal agents, has been observed. NAC spp., particularly C. parapsilosis and C. tropicalis, account for almost half of ICI. The increased use of antifungals in immunocompromised patients, mainly prophylactically, is considered the strongest contributory factor to the changes in species distribution, which have subsequently affected the mortality and choice of empirical treatment.

CONCLUSIONS

Prompt removal of lines and initiation of antifungal treatment are the milestones of management. Conventional amphotericin B remains a commonly used antifungal agent, but its lipid formulations and fluconazole are also used frequently. Novel antifungal agents such as second-generation triazoles and echinocandins exhibit potential as alternative agents in critically ill children with ICI. Although response rates are still far from satisfactory, improved understanding of risk factors, preventive strategies and new treatment options promise a better future outcome.

Successful medical treatment of cutaneous aspergillosis in a premature infant using liposomal amphotericin B, voriconazole and micafungin

Treatment options for primary cutaneous aspergillosis in neonates are limited by the lack of pharmacokinetic and safety data of newer antifungal agents that are effective against Aspergillus spp. We report the successful treatment of cutaneous aspergillosis in an extremely low-birth-weight preterm infant with liposomal amphotericin B, voriconazole and micafungin, and provide pharmacokinetic profiles for voriconazole and micafungin.

Antifungal therapy in children with invasive fungal infections: a systematic review

Invasive fungal infections are associated with significant morbidity and mortality. Differences between children and adults are reported, yet few trials of antifungal agents have been performed in pediatric populations. We performed a systematic review of the literature to guide appropriate pediatric treatment recommendations. From available trials that compared antifungal agents in either prolonged febrile neutropenia or invasive candidal or Aspergillus infection, no clear difference in treatment efficacy was demonstrated, although few trials were adequately powered. Differing antifungal pharmacokinetics between children and adults were demonstrated, requiring dose modification. Significant differences in toxicity, particularly nephrotoxicity, were identified between classes of antifungal agents. Therapy needs to be guided by the pathogen or suspected pathogens, the degree of immunosuppression, comorbidities (particularly renal dysfunction), concurrent nephrotoxins, and the expected length of therapy.

The Echinocandins

The changing pattern in fungal infections has driven the need to expand the targets of antifungal activity. The echinocandins are the newest addition to the arsenal against fungal infections. Three echinocandins have been approved by the United States Food and Drug Administration: caspofungin, micafungin, and anidulafungin. These agents have a broad spectrum of activity and are similar to each other with respect to in vitro activity against Candida sp, with micafungin and anidulafungin having similar minimum inhibitory concentrations (MICs) that are generally lower than the MIC of capsofungin. The MICs of the echinocandins are highest against Candida parapsilosis; however, whether this will affect clinical outcomes is unknown. Several case reports have identified clinical failure due to elevated MICs with caspofungin or micafungin against Candida albicans, Candida krusei, and C. parapsilosis. Resistance to the echinocandin class was present in some but not all of the isolates. Empiric therapy with one of the echinocandins for candidemia or invasive candidiasis in patients with neutropenia and those without neutropenia appears to be appropriate when one factors in mortality rate, the increasing frequency of non-albicans Candida infections, and the broad spectrum, safety, and fungicidal effect of the echinocandins. After speciation of the organism, continued therapy with an echinocandin can and should be reevaluated. The echinocandins demonstrate similar in vitro and in vivo activity against Aspergillus sp, but only caspofungin is approved for treatment in patients who are intolerant of or refractory to other therapies. Voriconazole and amphotericin B have demonstrated synergy with the echinocandins. The clinical response to combination therapy has been variable; however, the mortality rate appears to be lower with combination therapy than monotherapy. Large controlled trials are needed to determine the role of combination therapy for invasive aspergillosis. Micafungin and anidulafungin generally have a lower frequency of adverse reactions compared with caspofungin. Phlebitis (3.5-25% of patients) and elevated liver enzyme levels (1-15%) occur more often with caspofungin compared with micafungin and anidulafungin (< 8%). Overall, the three echinocandins are relatively safe and effective agents for the treatment of Candida infections.

Micafungin: A New Echinocandin Antifungal

The echinocandins represent the newest class of antifungals to combat infections caused by Candida sp. Micafungin is an echinocandin recently approved by the United States Food and Drug Administration. It is indicated in adults for esophageal candidiasis and prophylaxis against candidal infections in hematopoietic stem cell transplant recipients. Micafungin exhibits in vitro fungicidal activity against Candida sp, including fluconazole-resistant isolates. Its in vivo efficacy is comparable to that of fluconazole in the treatment of esophageal candidiasis and superior to that of fluconazole for prophylaxis of invasive candidal infections. Because it is not significantly metabolized by the cytochrome P450 3A system, micafungin is associated with few drug interactions. Micafungin does not require adjustment in patients with renal and/or hepatic impairment, and it has been shown to be well tolerated in both adult and pediatric patients. Its efficacy against Candida sp, coupled with its overall safety and drug interaction profiles, makes it an attractive option in the treatment against esophageal candidiasis and prophylaxis against invasive candidal infections.

The pharmacokinetics and safety of micafungin, a novel echinocandin, in premature infants

BACKGROUND

: Candidal fungal infection rates in neonates are increasing and are a significant cause of mortality, especially in low birth weight infants. Micafungin is an echinocandin that works by inhibiting 1,3-beta-D-glucan synthase, an enzyme responsible for fungal cell wall synthesis. The objective of this study was to determine the safety and pharmacokinetics of micafungin in premature infants.

METHODS

: This was a phase I, single-dose, multicenter, open-label, sequential-dose trial of intravenous micafungin investigating 3 doses (0.75 mg/kg, 1.5 mg/kg and 3.0 mg/kg) in 18 premature infants weighing >1000 g (n = 6 in each dosage group). A further 5 infants (500-1000 g) were enrolled in the 0.75 mg/kg dosage group only.

RESULTS

: The mean +/- standard deviation gestational age in the >1000 g dosage group was 26.4 +/- 2.4 weeks and, on entry, patients had one or more of a variety of underlying conditions, including sepsis, pneumonia and other infections caused by Candida or other species. Micafungin pharmacokinetics in preterm infants appears linear. However, premature infants >1000 g on average displayed a shorter half-life (8 hours) and a more rapid rate of clearance (approximately 39 mL/h per kg) compared with published data in older children and adults. All doses of micafungin were well tolerated and no serious drug-related adverse events were observed.

CONCLUSIONS

: Single doses of micafungin, ranging up to 3.0 mg/kg, appear well tolerated in premature infants weighing >1000 g. The drug's elimination half-life and total plasma clearance in preterm infants appear dissimilar to published values for these parameters in older children and adults. The reason(s) for this apparent difference remain to be investigated.

The echinocandins: comparison of their pharmacokinetics, pharmacodynamics and clinical applications

Caspofungin, micafungin and anidulafungin are three drugs of the echinocandin class of antifungals available for intravenous treatment of invasive candidiasis and aspergillosis. They exhibit high in vitro and in vivo activities against Candida spp. and Aspergillus spp. In various clinical studies investigating candidemia and invasive candidiasis, Candida esophagitis, and fever in neutropenia, the clinical efficacy of the echinocandin tested was similar to that of established antifungals. Antifungal activity against strains no longer susceptible to conventional antifungal agents, such as fluconazole and amphotericin B suggests that echinocandins can be used as salvage therapy in life-threatening fungal infections. There is no cross-resistance to other antifungals. Excellent safety and tolerability of treatment with caspofungin has been documented over a total of 4.3 million patient days. Echinocandins are poor substrates of the cytochrome P450 enzyme family and can be safely co-administered with most drugs without the need for dosage adaptation. No dose reduction is required in renal impairment. A reduction in the daily maintenance dose has been recommended for caspofungin, but not for micafungin and anidulafungin in patients presenting with mild to moderate hepatic failure.

Candin family antifungal agent micafungin (FK463) modulates the inflammatory cytokine production stimulated by lipopolysaccharide in THP-1 cells

Systemic inflammatory response syndrome (SIRS) and sepsis have been considered forms of hypercytokinemia in critically ill patients and immunocompromized hosts. It has been reported that some antimicrobial agents, including antifungal agents, not only have an antibiotic effect, but also they affect the host's immunological response. Immunofunctional cells, including monocytes and macrophages, were examined to determine whether they are influenced by the newly synthesized candin family antifungal agent micafungin (MCFG) using the human monocytic cell line THP-1 stimulated with lipopolysaccharide (LPS) as a model of hypercytokinetic conditions. LPS-induced production of TNF-alpha (tumor necrosis factor-alpha) and interleukin-8 (IL-8) in THP-1 cells was significantly suppressed dose-dependently by MCFG, although high concentrations of MCFG may reach toxic levels. It was clarified that MCFG inhibits the LPS-induced expression of TNF-alpha in THP-1 cells at the mRNA (messenger ribonucleic acid) level. In conclusion, administration of MCFG had an immunomodulatory effect on the host by reducing levels of TNF-alpha and IL-8. The effectiveness of MCFG in modulating hypercytokinemia is due not only to its direct antifungal effect, but also to the modulation of cytokine production in macrophages that regulates immunological activity and inflammation.

Mycoses in Pediatric Patients

For more than 40 years, there has been limited progress in the treatment of invasive fungal infections. There are now numerous nuances to choosing the appropriate antifungal agent. Important advantages have been achieved in understanding the safety, tolerability, and pharmacokinetics of these agents. One of the most important aspects for successful management of pediatric invasive fungal infections is an understanding of the differences in the pharmacokinetics of the drugs in children and adults to offer optimal dosing strategies. Unfortunately there have been few antifungal studies conducted in children. Consequently most information for the pediatrician has been extrapolated from adult data. The breadth of antifungal data in children is expanding, however, with newer studies underway. Through the efforts of dedicated clinicians and collaboration, pediatric indications and dosing strategies will eventually be discovered that directly benefit pediatric patients.

Clinical efficacy of new antifungal agents

Several new options are now available for treating serious fungal infections. All three echinocandin agents currently available have been shown in randomized, blinded clinical trials to be efficacious in treating candidemia and invasive candidiasis. By contrast, the demonstrated efficacy of the echinocandins for the treatment of invasive aspergillosis has been based on historically controlled salvage treatment trials in patients failing or intolerant of other therapies. The new triazole agents, voriconazole and posaconazole, have a broad spectrum of antifungal activity. Voriconazole has become the agent of choice for invasive aspergillosis. On the basis of compassionate treatment data, posaconazole appears to be effective for treatment of zygomycosis. These agents have also been shown to be effective in the treatment of non-Aspergillus mould infections, several of the endemic mycoses and serious Candida infections.

Emerging echinocandins for treatment of invasive fungal infections

The echinocandins are a new class of antifungals, developed in response to the need for safe and effective antifungals for the treatment of invasive fungal infections. These agents work by inhibiting 1,3-beta-d-glucan synthase, an enzyme essential for production of cell walls in select fungi. Echinocandins appear to demonstrate favourable activity in vitro against a variety of yeasts (including both Candida albicans and non-albicans Candida) as well as select moulds (including Aspergillus spp.) In general, all echninocandins demonstrate a favourable safety profile and require once-daily parenteral administration. Caspofungin is the first of these agents to be available in the US, and is approved for empirical antifungal therapy in febrile neutropenic patients, candidaemia and select forms of invasive candidiasis, and for management of invasive aspergillosis in patients refractory to or intolerant of other therapies. Micafungin was recently approved by the FDA for treatment of oesophageal candidiasis, and for the prophylaxis of fungal infections in haematopoietic stem cell transplant recipients. Emerging data indicate micafungin may have an important role in the treatment of invasive forms of candidiasis. Anidulafungin is an echinocandin approved in the US for treatment of candidaemia and oesophageal candidiasis. Aminocandin (HMR-3702, IP-960) is an investigational agent, with published experience limited to in vitro studies and animal models of infection.

Micafungin: a new echinocandin

Micafungin, a potent inhibitor of 1,3-beta-D-glucan synthase, has become the second available agent in the echinocandins class that is approved for use in clinical practice. This agent shares with caspofungin an identical spectrum of in vitro activity against Candida albicans, non-albicans species of Candida, and Aspergillus species, as well as several but not all pathogenic molds. If anything, its in vitro activity appears to be superior to that of caspofungin, although the clinical relevance of this observation is unclear. The clinical role of micafungin appears to be similar to that of caspofungin, although clinical data are still lacking at this stage, with initial approval only for treatment of esophageal candidiasis and prophylaxis in subjects with neutropenia. Pharmacokinetic and pharmacodynamic studies and reports of adverse effects and safety have reported similar but not identical results to those of other agents in the echinocandin class. Factors such as acquisition costs and the potential for resistance development may be more relevant to its widespread use than in vitro and in vivo data comparisons with caspofungin.

Treatment with caspofungin in immunocompromised paediatric patients: a multicentre survey

OBJECTIVES

Although a paediatric dosage has not been established, caspofungin is occasionally used in paediatric patients. We conducted a multicentre retrospective survey to obtain data on immunocompromised paediatric patients considered to require caspofungin therapy.

METHODS

The survey identified 64 patients (median age: 11.5 years; 25 females, 39 males) with haematological malignancies (48), marrow failure (9), solid tumours (3), haematological disorders (2) and congenital immunodeficiency (2) who received caspofungin for proven (17), probable (14) and possible (17) invasive fungal infections or empirically (16). Caspofungin was administered until intolerance or maximum efficacy at dosages individually determined by the responsible physician for refractory infection (38), intolerance of other agents (10) or as best therapeutic option (16).

RESULTS

The 64 patients received caspofungin for a median of 37 days (range 3-218) as single agent (20) or in combination (44). The median daily maintenance dosage was 1.07 mg/kg (95% CI 1.09-1.35; range 0.40-2.92) or 34.3 mg/m2 (95% CI 32.3-37.3; range 16.3-57.5). In none of the patients was therapy discontinued due to adverse events (AEs). Clinical AEs were mild to moderate and observed in 34 patients (53.1%). While mean glutamate pyruvate transaminase and glutamate oxalate transaminase values were slightly (P < 0.005) higher at the end of treatment (EOT), serum bilirubin, alkaline phosphatase and creatinine values were not different from baseline. Complete responses, partial responses or stabilization were observed in 5/7/3 of 17 patients with proven, in 3/4/3 of 14 patients with probable and in 7/6/1 of 15 evaluable patients with possible invasive infections. Thirteen of 16 patients on empirical therapy completed without breakthrough infection. Overall survival was 75% at the EOT and 70% at 3 months post-EOT, respectively.

CONCLUSIONS

Caspofungin displayed favourable safety and tolerance and may have useful antifungal efficacy in severely immunocompromised paediatric patients.

Linear Pharmacokinetics of Micafungin and Its Active Metabolites in Japanese Pediatric Patients with Fungal Infections

The objective of this study was to propose the appropriate dosage regimen of micafungin for pediatric use, considering the effects of dose-linearity, age and other cofactors on the pharmacokinetics. Pharmacokinetic analysis of micafungin and its active metabolites (M1 and M2) after intravenous infusion at doses of 1 to 3 mg/kg was conducted for 19 Japanese pediatric patients (3 infants, 7 toddlers, and 9 pupils) with deep mycosis caused by either Aspergillus or Candida species. One patient was given the maximum dose of 6 mg/kg. The Cmax of micafungin increased in proportion to the dose. The mean values (S.D.) were 5.03 (2.33), 10.25 (4.45), 14.8 (5.52) and 21.1 microg/ml at 1, 2 , 3 and 6 mg/kg, respectively. These parameters were comparable to those seen in adults when the parameter was normalized by body weight. The elimination half life (t1/2) of micafungin over the dose range was apparently constant with the value of 13.1 h. There was no difference between the age groups observed. In fact, the metabolite concentrations were almost the same as those obtained for non-pediatric patients. Thus, micafungin showed the same dose-proportional pharmacokinetics in pediatric patients as it did in adults. No age dependent pharmacokinetics were observed in this study. It was concluded that the body weight adjustment was adequate for the treatment of micafungin in pediatric patients.

Population Pharmacokinetic Analysis of Micafungin in Japanese Patients with Fungal Infections

The object of this analysis was to develop a population pharmacokinetic model of micafungin, a new anti-fungal agent of the echinocandin class, to optimize dosing in Japanese patients with fungal infections. Population pharmacokinetics parameters were determined using NONMEM based on pharmacokinetic data from 198 subjects in seven clinical studies, comprising four phase I, two phase II and one pediatric phase III study. The healthy subjects received intravenous infusion of 2.5-150 mg micafungin. Adult and pediatric patients, age range of 8 month to 15 yeras old, were received 25-150 mg and 1-6 mg/kg daily, respectively. A total of 1825 micafungin plasma samples were available for this analysis. Two-compartment pharmacokinetic model was adopted. The clearance of micafungin was influenced by body weight in children and platelet counts (PLT). However the PLT accounted for less than 20% of the variation of micafungin clearance in Japanese subjects. In conclusions, body weight is the primary covariate factor in pediatric patients. The dose adjustment by body weight would be required only pediatric patients for the micafungin therapy in Japanese patients with fungal infection.

New antifungal agents under development in children and neonates

PURPOSE OF REVIEW

This review focuses on only the newest antifungal agents recently approved or still under development and the available data in pediatric and neonatal patients. The larger body of data in adult patients is used for comparative purposes only in an attempt to understand pediatric implications.

RECENT FINDINGS

Pharmacokinetic data suggest differences in dosing for many newer agents in children versus adult patients, but each agent has not been fully evaluated. Voriconazole displays non-linear pharmacokinetics in adults but has linear pharmacokinetics in children, necessitating a higher dose in smaller patients and potential treatment failures using the approved adult dosing schedule. Caspofungin likewise requires higher doses relative to adult patients, and dosing in children is best accomplished on a body surface area scheme and not a body weight dosing platform. Preliminary data suggest posaconazole, an investigational triazole, in children may lead to similar levels as in adults, but very limited efficacy data are available at any dose. Micafungin dosing has been explored in neonatal patients and there is a clear trend toward lower levels obtained in the very smallest infants, highlighting the importance of the neonatal period as a separate entity to even the pediatric age group.

SUMMARY

Initial data suggest dosing differences in children with some antifungals, and other newer agents have not been fully tested for the correct dosing. The underlying concern of efficacy in children compared with adult patients has never been answered as there are no randomized, phase III antifungal clinical trials from which pediatric-specific data were obtained.

Management of neonatal candidiasis. Neonatal Candidiasis Study Group

OBJECTIVE

To identify areas of consensus and controversy in the management of neonatal candidiasis.

METHODS

A questionnaire was distributed to US-based members of the Pediatric Infectious Diseases Society and a sampling of US neonatologists.

RESULTS

Three hundred eighty evaluable questionnaires were returned (42% of those mailed). Ninety-five percent of respondents have cared for an infant with systemic candidiasis in the past 2 years. Fluconazole and liposomal amphotericin are used to some extent by 90 and 69% of respondents, respectively. A single blood culture positive for Candida led to a recommendation for immediate treatment by 99%; amphotericin B was the preferred therapy for candidemia (88%). More than 80% of respondents would request cerebrospinal fluid, urine and repeat blood cultures and ophthalmologic examination in the evaluation of candidemia. If a cerebrospinal fluid culture is positive, 25% would use amphotericin B alone whereas 62% would add flucytosine. For candiduria Society members chose fluconazole therapy more often than did neonatologists, 23% vs. 3.4% (P<0.001). There was no consensus concerning duration of therapy, use of an amphotericin B test dose or management of a central catheter in place during candidemia.

CONCLUSIONS

Systemic candidiasis in neonates is a frequently encountered clinical problem. There is agreement that prompt therapy with amphotericin B is required if a blood culture is positive for Candida and that such infants require additional evaluations. Other antifungals (fluconazole, liposomal amphotericin B) are used to some extent in this population. Many issues in management have no clear consensus and warrant further research.