Invasive Fungal Infections

N umerous reports have described the increasing problem of nosocomial invasive fungal infections (IFI) in immunocompromised patients (1, 2). This is due to the increased number of at-risk patients in parallel with progress in intensive care and/or hematology, leading to deeper or longer immunosuppression (3). In parallel, the spectrum of isolated fungi has shifted from well-known opportunistic pathogens with characterized virulence factors (4, 5) to other species rarely reported to be a cause of human infection (6–8). Disruptions in the microbial balance induced by antibacterial antibiotics favor fungal fitness (9). Antifungal therapy is generally prescribed in patients with persistent fever despite 3 days of antibiotic treatment (10). Diagnostic strategies involve conventional methods of isolation and identification of fungi from blood or sterile sites, imaging, and a panel of biological tests whose nature depends on the fungal agent suspected (11, 12). The few biological tests currently considered by physicians to be of diagnostic help do not involve changes in the host response related to fungal infections (e.g., antifungal antibodies [13] or cytokine profiling [14]) but consist of the detection of circulating fungal molecules, either glycans or DNA, in the patients’ sera using tests developed with the advent of hybridoma technology (15, 16), discoveries in biochemical cascades (17), or PCR (18). Due to the poor sensitivity of conventional mycological methods (12, 19), infectious disease societies have produced different levels of recommendations for immunological tests for the diagnosis of invasive candidiasis (IC) and invasive aspergillosis (IA) (20, 21). These tests, which are considered specific but which sometimes lack sensitivity, were later complemented by recommendations for the more sensitive Fungitell test, which detects both IC and IA (22). Despite years of extensive research into the detection of fungal DNA, a consensus has been reached only for IA, while standardization is still in progress for IC and mucormycosis (MM) (23). For MM, a standardized PCR method would be of primary interest since, in contrast to IC, glycan detection tests are not available (24). Recently, the T2MR technology, combining DNA amplification and detection by magnetic reso- nance, has provided significant progress in terms of reducing the delay in the time to diagnosis in comparison with the time to diagnosis by blood cultures for IC (25). More recently, matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry (MS) has become essential in clinical mycology laboratories, providing a more rapid and accurate means of identification of fungal species isolated from patients (26).

Posaconazole (Noxafil; Merck & Co, Inc., Whitehouse Station, NJ, USA) is a broad- spectrum antifungal agent that is used both as antifungal prophylaxis and treatment against invasive fungal infections. This azole antifungal agent, like the other members of this class, inhibits the enzyme 14 α -demethylase, which is responsible for the conver- sion of lanosterol to ergosterol, thereby inhibiting the biosynthesis of this cell membrane component. Posaconazole was the third extended-spectrum triazole to be approved for use against invasive fungal infections, following the availability of itraconazole and voriconazole. Similar to voriconazole, posaconazole has potent in vitro activity against yeasts, including Candida species, as well as Cryptococcus neoformans and Cryptococcus gattii. 1,2 Both voriconazole and posaconazole also exhibit antifungal activity against

lying diseases were included: hematologic malignancy, solid tumors, transplant (either solid organ or hematopoietic cell transplantation), acquired immunodeficiency syndrome, and other diagnoses. Overall, the prevalence of invasive fungal infections was 8.2%. Invasive fungal infection rates were tabulated by time periods in order to evaluate trends, and were as follows: 1993–1996 (6.6%), 1997–2000 (8.6%), and 2001–2005 (10.4%). The highest prevalence was found in patients with hematologic malignancy (33%), followed by transplant (22.9%), acquired immunodeficiency syndrome (19.7%), solid tumors (4.8%), followed by other diagnoses (3.5%). The most common infecting fungal organisms were Aspergillus species, then Candida species. Other fungal organisms (eg, Cryptococcus species and Zygomycetes) were all found in approximately 1% or less of the cases reviewed. The study did note that the prevalence of invasive fungal infection decreased over time in the transplant group when comparing the 1997–2000 and 2001–2005 periods. As noted earlier, this is most likely attributable to the use of antifungal prophylaxis in the transplant population.

While this study does provide real world comparative data regarding the use of azole antifungals in invasive fungal infections, it does have several limitations. Given the retrospective nature of the study, there may be an inherent bias for the initial selection of azole antifungals for treatment, which was evident in baseline character- istic differences between the groups. The study was also not designed to evaluate for outpatient treatment or effects following discharge outside of 30-day readmis- sion. Given the single center nature of the study, clinical practice and regional fungal biome differences may limit the external validity of the data. While this study helps to provide baseline comparisons of treatment options for invasive fungal infections, pragmatic prospective stud- ies are needed to illuminate the roles each of the broad

Abstract: Objective: BG40018 is a semisynthetic echinocandin derived from anidulafungin. This study was con- ducted to evaluate the pharmacokinetics and efficacy of BG40018. Methods: The in vitro antifungal activities of BG40018 and anidulafungin were determined using CLSI broth microdilution methods and time-killing test. The pharmacokinetics of BG40018 and anidulafungin were compared in beagle dogs after 10-minute intravenous infu- sion at 1 mg/kg. Comparison of the in vivo potency was studied in a murine systemic candidiasis model, the kid- ney fungal burden, pathological examination and survival rate were evaluated after treatment. Results: BG40018 showed comparable in vitro antifungal activities to anidulafungin. Pharmacokinetics of BG40018 in the dogs re- sult indicated that BG40018 exhibited longer elimination half-life and higher exposure compared to anidulafungin. BG40018 displayed more potent in vivo efficacy against infections by reducing fungal burdens in kidney with im- provement of pathological damage compared to anidulafungin. In addition, BG40018 demonstrated higher survival rate in a murine systemic candidiasis model than anidulafungin. Conclusions: All the data above support the char- acterization of BG40018 as a promising long-acting drug candidate for the treatment of serious, life-threatening, invasive fungal infections, and it will be investigated further for future clinical use.

immunosuppression in (bacterial) sepsis patients [53], in patients with invasive fungal infections. In all IFN-γ treated patients who showed baseline mHLA-DR levels below the immunoparalysis threshold of 50% and sur- vived, IFN-γ mediated upregulation of mHLA-DR ex- pression was observed. In agreement with the data presented in this case series, rIFN-γ has been shown to significantly increase numbers of HLA-DR-positive monocytes both in a human preclinical bacterial sepsis model and in septic patients [31,54]. Reduced produc- tion of TNFα by leukocytes ex-vivo stimulated with LPS has also been shown to be marker of immunoparalysis in sepsis patients. In contrast to our study, mHLA-DR expression and ex-vivo TNFα production were found to be highly correlated in bacterial sepsis patients [54,55]. A possible explanation for this discrepancy is that, in contrast with the emerging consensus that immunopara- lysis renders patients more vulnerable to opportunistic infections in general [53], different defects in immune defences may be responsible for enhanced susceptibility towards different pathogens.

The diagnosis of invasive fungal infections (IFIs) is usually based on the isolation of the fungus in culture and histopathological techniques. However, these methods have many limitations often delaying the definitive diagnosis. In recent years, molecular diagnostics methods have emerged as a suitable alternative for IFI diagnosis. When there is not a clear suspicion of the fungus involved in the IFI, panfungal real-time PCR assays have been used, allowing amplification of any fungal DNA. However, this approach requires subsequent amplicon sequencing to identify the fungal species involved, increasing response time. In this work, a new panfungal real-time PCR assay using the combination of an intercalating dye and sequence-specific probes was de- veloped. After DNA amplification, a melting curve analysis was also performed. The technique was standardized by using 11 dif- ferent fungal species and validated in 60 clinical samples from patients with proven and probable IFI. A melting curve database was constructed by collecting those melting curves obtained from fungal species included in the standardization assay. Results showed high reproducibility (coefficient of variation [CV] < 5%; r > 0.95) and specificity (100%). The overall sensitivity of the technique was 83.3%, with the group of fungi involved in the infection detected in 77.8% of the positive samples with IFIs cov- ered by molecular beacon probes. Moreover, sequencing was avoided in 67.8% of these “probe-positive” results, enabling report of a positive result in 24 h. This technique is fast, sensitive, and specific and promises to be useful for improving early diagnosis of IFIs.

Abstract: Posaconazole is a triazole antifungal agent that has broad-spectrum activity against many yeasts and filamentous fungi, including Candida species, Cryptococcus neoformans, Aspergillus species, and Zygomycetes. This drug has been approved for the prevention of invasive fungal infections in patients with neutropenia and for the treatment of invasive fungal infections in hematopoietic stem cell transplant recipients with graft-versus-host disease. Stud- ies on the clinical efficacy, safety, tolerability, and cost-effectiveness of posaconazole therapy were performed using the oral suspension form of the drug. Pharmacokinetic studies have found that the oral suspension form of posaconazole has problemeatic bioavailability: its absorption is affected by concomitant medication and food. This article discusses the pharmacokinetic properties of the newly developed posaconazole delayed-release tablet formulation and reviews the efficacy, safety, and cost-effectiveness of both the oral suspension and the new tablet formu- lation. In conclusion, the posaconazole tablet formulation has better systemic bioavailability, thereby enabling once-daily administration and better absorption in the presence of concomitant medication and food. However, well-designed clinical studies are needed to evaluate the use of the tablet formulation in real-life settings.

Abstract: Despite recent advances in both diagnosis and prevention, the incidence of invasive fungal infections continues to rise. Available antifungal agents to treat invasive fungal infections include polyenes, triazoles, and echinocandins. Unfortunately, individual agents within each class may be limited by spectrum of activity, resistance, lack of oral formulations, significant adverse event profiles, substantial drug–drug interactions, and/or variable pharmacokinetic profiles. Isavuconazole, a second-generation triazole, was approved by the US Food and Drug Administration in March 2015 and the European Medicines Agency in July 2015 for the treatment of adults with invasive aspergillosis (IA) or mucormycosis. Similar to amphotericin B and posaconazole, isavuconazole exhibits a broad spectrum of in vitro activity against yeasts, dimorphic fungi, and molds. Isavuconazole is available in both oral and intravenous formu- lations, exhibits a favorable safety profile (notably the absence of QTc prolongation), and reduced drug–drug interactions (relative to voriconazole). Phase 3 studies have evaluated the efficacy of isavuconazole in the management of IA, mucormycosis, and invasive candidiasis. Based on the results of these studies, isavuconazole appears to be a viable treatment option for patients with IA as well as those patients with mucormycosis who are not able to tolerate or fail amphotericin B or posaconazole therapy. In contrast, evidence of isavuconazole for invasive candidiasis (relative to comparator agents such as echinocandins) is not as robust. Therefore, isavuconazole use for invasive candidiasis may initially be reserved as a step-down oral option in those patients who cannot receive other azoles due to tolerability or spectrum of activity limitations. Post-marketing surveillance of isavuconazole will be important to better understand the safety and efficacy of this agent, as well as to better define the need for isavuconazole serum concentration monitoring.

I nvasive candidiasis (IC) and invasive aspergillosis (IA) are major life-threatening nosocomial invasive fungal infections (IFIs) (1– 3). Although less prevalent, mucormycosis (MM) is an emerging problem. Progress in antifungal therapy has not significantly re- duced the high rates of morbidity and mortality associated with IFIs, particularly in intensive care units (ICUs) and oncohematol- ogy units (4–6), due to difficulties in obtaining an early diagnosis, an important condition for a favorable outcome (7). Difficulties in the biological detection of IFIs are related to the low yield of cul- ture-based methods (8); blood cultures are positive in only ⬃50% of episodes of IC and in anecdotic cases of IA. To fill this gap, methods have been developed for the detection of fungal mole- cules in sera from patients (9–11). These methods include the detection of fungal DNA in body fluids and tissues, for which no consensual recommendations have been produced due to the lack of standardization. In contrast, there is extensive literature on the diagnostic value of fungal polysaccharide detection, including (1,3)- ␤ - D -glucan (BDG) (12), present in Candida and Aspergillus

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 recommenda- tions. 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.

94) Dimitrios P Kontoyiannis, Kieren A Marr, Benjamin J Park, Barbara D Alexander, Elias J Anaissie, Thomas J Walsh, James Ito, David R Andes, John W Baddley, Janice M Brown, Lisa M Brumble, Alison G Freifeld, Susan Hadley, Loreen A Herwaldt, Carol A Kauffman, Katherine Knapp, G Marshall Lyon, Vicki A Morrison, Genovefa Papanicolaou, Thomas F Patterson, Trish M Peri, Mindy G Schuster, Randall Walker, Kathleen A Wannemuehler, John R Wingard, Tom M Chiller And Peter G Pappas. Prospective surveillance for invasive fungal infections in Hematopoietic stem cell transplant recipients, 2001-2006: overview of the Transplant- Associated Infection Surveillance Network(TRANSNET) database. bnv 2010;50: 1091-100

Another clinical trial (NCT00412893) with isavuconazole has already completed enrollment. This was a double-blind, randomized study called SECURE, that aimed to compare the efficacy and safety of isavuconazole versus voriconazole in the primary treatment of IFDs caused by Aspergillus or other filamentous fungi. Primary outcome measure was mortality through day 42 after treatment, and secondary outcome mea- sures were clinical, mycological, and radiological response. The inclusion criterion was the diagnosis of probable or proven IFD caused by Aspergillus species or other filamen- tous fungi. Patients with other invasive fungal infections (neither Aspergillus nor filamentous fungi), chronic asper- gillosis (either aspergilloma or allergic bronchopulmonary aspergillosis), previous systemic antifungal therapy other than fluconazole, or body weight under 40 kg were excluded from the study. 33 Astellas Pharma has recently reported, in a

significant morbidity and mortality among individuals with impaired immunity [1-3]. Despite recent advances in the care of patients with IFI, conventional therapeutic options remain limited, and outcomes poor. A potential strategy to improve this is to reverse underlying immune deficits, or modify and enhance host immune responses using immunomodulatory treatments. However, immune responses against fungal pathogens are diverse, and detailed understanding of the underlying immunology is essential to enable effective interventions. Here we review recent advances in immunomodulatory therapies for treatment and prevention of invasive fungal infections. A summary of the main findings is given in Table 1.

infections may be fatal, others that are subcutaneous and superficial infections affecting the skin, mucous membranes, and keratinous tissues, which can still lower patients’ quality of life considerably. 2 Candida albicans, the most prominent pathogenic species are observed in 17% of the patients treated in the intensive care unit (ICU), and these infections are greatly associated with mortality and morbidity. 3 Diagnostic delays, low sensitivity, difficulty in the discrimination of colonization from invasive candidiasis, limitations in current diagnostic techniques are the present challenges in the treatment programs of fungal infections. 4 The clinical outcome of patients with invasive fungal infections depend significantly on host related factors rather than the virulence of fungal organism. In addition, understanding the role of various co morbid conditions in the causation of fungal infections can help achieve improve early treatment goals and improve the overall outcome of the patient. The present study was undertaken to study the risk factor, clinical and radiological profile of the patients of invasive /systemic fungal infections.

The azoles enact their antifungal effects within the fungal cell membrane by blocking the P450 (CYP)-dependent d emethylation of lanosterol, leading to the inhibition of ergosterol synthesis (Figure 1). This process causes toxic methylsterols to accumulate in the fungal cell membrane and prevents fungal cell growth and replication. Differences between azoles in antifungal potency and activity are attrib- uted to differences in their affinity for the 14- α -demethylase enzyme. The toxicity and drug interaction profiles of the azoles, including voriconazole, are due to cross-inhibition of various human CYP-dependent enzymes. Voriconazole, like other triazoles, is fungistatic against most yeasts but has fungicidal activity against molds, including Aspergillus. 8–10

to both good effi cacy and safety (Rex et al 1994). Amphotericin B is equally effi cacious, but is limited by toxicity. The effi cacy of fl uconazole was recently compared with that of anidulafun- gin in the treatment of invasive candidiasis (Reboli et al 2007). In this double-blind study, 261 patients were enrolled and then stratifi ed by APACHE score and presence of neutropenia. Patients were randomized to treatment with anidulafungin (200 mg loading dose then 100 mg daily) or intravenous fl uconazole (800 mg loading dose then 400 mg daily), with the option to switch to oral fl uconazole therapy after at least 10 days of intravenous therapy. Therapy was continued for 14 days after a negative blood culture and absence of signs and symptoms. The most common isolates were C. albicans (61.6%), C. glabrata (20.4%), and C. parapsilosis (11.8%). Successful outcomes were achieved in 75.6% treated with anidulafungin compared to 60.2% treated with fl uconazole group (15.4% difference, 95% confi dence interval: 3.9–27.0). Thus anidulafungin was superior to standard therapy. Patients receiving anidulafungin had higher rates of successful response for all Candida isolates with the exception of C. parapsilosis. However, the superiority of anidulafungin may be questioned due to a potential center effect. One center enrolled a total of 25 patients, and 14 of 15 patients treated with anidulafungin (93.3%) at the center compared to 5 of 10 patients treated with fl uconazole (50%) had successful response. Removal of patients from this center makes anidulafungin non-inferior to fl uconazole and not superior.

T, Pappas PG, Maertens J, Lortholary O, Kauffman CA, Denning DW, Patterson TF, Maschmeyer G, Bille J, Dismukes WE, Herbrecht R, Hope WW, Kibbler CC, Kullberg BJ, Marr KA, Muñoz P, Odds FC, Perfect JR, Restrepo A, Ruhnke M, Segal BH, Sobel JD, Sorrell TC, Viscoli C, Wingard JR, Zaoutis T, Bennett JE, European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Co- operative Group, National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group. 2008. Revised definitions of invasive fungal disease from the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Coopera- tive Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group. Clin. Infect. Dis. 46:1813–1821. http://dx.doi.org/10.1086/588660.

Invasive fungal infections are on the rise. Convention- al amphotericin B (c-amB) and azole antifungals have been the mainstay of antifungal therapy into the last decade. The high incidence of infusion-related toxicity and nephrotoxicity associated with camB and the emergence of fluconazole-resistant strains of Candida glabrata prompted a search for alternatives. Echino - candins are a new class of antifungal drugs that act by inhibition of beta-(1,3)-d-glucan synthase, a key en- zyme necessary for the integrity of the fungal cell wall. Caspofungin was the first drug licensed drug in this class. It is indicated for esophageal candidiasis, can- didemia, invasive candidiasis, empirical therapy in pa- tients with febrile neutropenia and may be used for salvage therapy in patients with invasive aspergillosis. Response rates are generally comparable to those of amphotericin B and fluconazole. Micafungin is pre - sently approved for esophageal candidiasis, invasive candidiasis including candidemia and for prophylaxis of Candida infections in patients undergoing allogene- ic HsCT. The currently approved indications for anidulafungin are esophageal candidiasis, candidemia and invasive candidiasis. The incidence of infusion-re- lated adverse effects and nephrotoxicity is much lower

Early intervention in the therapy of invasive can- didiasis in high-risk populations was designed to reduce morbidity and improve survival substan- tially. The rationale for empirical antifungal therapy in high-risk persistently febrile neutropenic patients is the early treatment of clinically occult disease, the prevention of disseminated candidiasis, and the pre- vention of invasive fungal infections. In response to the increasing incidence and inherent difficulty in diagnosing candidiasis and candidemia, investiga- tors in the field of oncology developed a well-known clinical predictive model on which to initiate empir- ical antifungal therapy. Empirical antifungal therapy is initiated after 5 to 7 consecutive days of fever and neutropenia. 7,8 This model was based on a complete