Treatment of Chronic Granulomatous Disease-Related Pulmonary Aspergillus Infection in Late Pregnancy

A global perspective of the changing epidemiology of invasive fungal disease and real-world experience with the use of isavuconazole

Global epidemiological data show that the incidence of invasive fungal disease (IFD) has increased in recent decades, with the rising frequency of infections caused by Aspergillus and Mucorales order species. The number and variety of patients at risk of IFD has also expanded, owing in part to advances in the treatment of hematologic malignancies and other serious diseases, including hematopoietic stem cell transplantation (HCT) and other therapies causing immune suppression. Isavuconazonium sulfate (active moiety: isavuconazole) is an advanced-generation triazole antifungal approved for the treatment of invasive aspergillosis and mucormycosis that has demonstrated activity against a variety of yeasts, moulds, and dimorphic fungi. While real-world clinical experience with isavuconazole is sparse in some geographic regions, it has been shown to be effective and well tolerated in diverse patient populations, including those with multiple comorbidities who may have failed to respond to prior triazole antifungal therapy. Isavuconazole may be suitable for patients with IFD receiving concurrent QTc-prolonging therapy, as well as those on venetoclax or ruxolitinib. Data from clinical trials are not available to support the use of isavuconazole prophylactically for the prevention of IFD or for the treatment of endemic IFD, such as those caused by Histoplasma spp., but real-world evidence from case studies suggests that it has clinical utility in these settings. Isavuconazole is an option for patients at risk of IFD, particularly when the use of alternative antifungal therapies is not possible because of toxicities, pharmacokinetics, or drug interactions.

Antifungal Drugs TDM: Trends and Update

PURPOSE

The increasing burden of invasive fungal infections results in growing challenges to antifungal (AF) therapeutic drug monitoring (TDM). This review aims to provide an overview of recent advances in AF TDM.

METHODS

We conducted a PubMed search for articles during 2016-2020 using "TDM" or "pharmacokinetics" or "drug-drug-interaction" with "antifungal," consolidated for each AF. Selection was limited to English language articles with human data on drug exposure.

RESULTS

More than 1000 articles matched the search terms. We selected 566 publications. The latest findings tend to confirm previous observations in real-life clinical settings. The pharmacokinetic variability related to special populations is not specific but must be considered. AF benefit-to-risk ratio, drug-drug interaction (DDI) profiles, and minimal inhibitory concentrations for pathogens must be known to manage at-risk situations and patients. Itraconazole has replaced ketoconazole in healthy volunteers DDI studies. Physiologically based pharmacokinetic modeling is widely used to assess metabolic azole DDI. AF prophylactic use was studied more for Aspergillus spp. and Mucorales in oncohematology and solid organ transplantation than for Candida (already studied). Emergence of central nervous system infection and severe infections in immunocompetent individuals both merit special attention. TDM is more challenging for azoles than amphotericin B and echinocandins. Fewer TDM requirements exist for fluconazole and isavuconazole (ISZ); however, ISZ is frequently used in clinical situations in which TDM is recommended. Voriconazole remains the most challenging of the AF, with toxicity limiting high-dose treatments. Moreover, alternative treatments (posaconazole tablets, ISZ) are now available.

CONCLUSIONS

TDM seems to be crucial for curative and/or long-term maintenance treatment in highly variable patients. TDM poses fewer cost issues than the drugs themselves or subsequent treatment issues. The integration of clinical pharmacology into multidisciplinary management is now increasingly seen as a part of patient care.

Hematopoietic Stem Cell Transplantation Cures Therapy-refractory Aspergillosis in Chronic Granulomatous Disease

BACKGROUND

Pulmonary invasive aspergillosis is a frequent and life-threatening complication for patients with chronic granulomatous disease (CGD). Despite combined treatment with several groups of antifungal agents, conservative treatment of invasive aspergillosis often remains refractory. Pulmonary invasive aspergillosis is often treated by surgical resection of consolidated lobes or segments, donor granulocyte transfusions and allogeneic hematopoietic stem cell transplantation (HSCT). These options are not mutually exclusive and often combined.

METHODS AND RESULTS

We here describe the treatment of 3 patients with CGD who received HSCT upon active pulmonary invasive aspergillosis: Two of them received HSCT as salvage therapy for refractory aspergillosis, and 1 patient received elective HSCT in infancy but developed pulmonary aspergillosis during secondary graft failure. Based on our experience and available literature, we discuss indication as well as timing of HSCT, granulocyte transfusions and surgery in patients with CGD and pulmonary invasive aspergillosis.

CONCLUSIONS

Upon diagnosis with invasive aspergillosis in CGD, we propose to start antifungal treatment and preparation for HSCT at the same time. Remission of pulmonary invasive aspergillosis before HSCT remains preferable but is not mandatory. When pulmonary aspergillosis in patients with CGD remains refractory for longer than 3 months on conservative treatment, HSCT without prior surgery or accompanying granulocyte transfusions is a feasible option.