Tolerability of long-term fluconazole therapy

Novel antifungals and treatment approaches to tackle resistance and improve outcomes of invasive fungal disease

SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.

Challenges Facing Antimicrobial Stewardship Programs in the Endemic Region for Coccidioidomycosis

Coccidioidomycosis poses a significant cost and morbidity burden in the United States. Additionally, coccidioidomycosis requires constant decision-making related to prevention, diagnosis, and management. Delays in diagnosis lead to significant consequences, including unnecessary diagnostic workup and antibacterial therapy. Antifungal stewardship considerations regarding empiric, prophylactic, and targeted management of coccidioidomycosis are also complex. In this review, the problems facing antimicrobial stewardship programs (ASPs) in the endemic region for coccidioidomycosis, consequences due to delayed or missed diagnoses of coccidioidomycosis on antibacterial prescribing, and excess antifungal prescribing for prevention and treatment of coccidioidomycosis are elucidated. Finally, our recommendations and research priorities for ASPs in the endemic region for coccidioidomycosis are outlined.

Safety and pharmacokinetics of antifungal agent VT-1598 and its primary metabolite, VT-11134, in healthy adult subjects: phase 1, first-in-human, randomized, double-blind, placebo-controlled study of single-ascending oral doses of VT-1598

VT-1598 is a novel fungal CYP51 inhibitor and 1-tetrazole-based antifungal drug candidate with improved selectivity minimizing off-target binding to and inhibition of human CYP450 enzymes. Data are presented from this first clinical study in the evaluation of the safety and pharmacokinetic (PK) of single ascending doses of 40, 80, 160, 320, and 640 mg VT-1598, comprising a 160 mg cohort in both fasting and fed states. Eight healthy adults per dose were randomized to receive either oral VT-1598 or placebo (3:1). Over the dose range, exposures were with relatively high variation. The maximum plasma concentrations (Cmax) for VT-1598 were 31.00-279.4 ng/ml and for its primary metabolite, VT-11134, were 27.80-108.8 ng/ml. The plasma area under the concentration-time curve to the last measurable concentration (AUC0-last) for VT-1598 were 116.1-4507 ng*h/ml, and for VT-11134 were 1140-7156 ng*h/ml. The dose proportionality was inconclusive based on the results of the power model. The peak concentration time (Tmax) was 4-5 h for VT-1598 and for VT-11134. Half-life was 103-126 h for VT-11134. After food intake, Cmax of VT-1598 increased by 44% (geometric mean ratio (GMR), 1.44; 90%CI [0.691, 2.19]) and AUC0-last by 126% (GMR, 2.26; 90%CI [1.09, 3.44]), while exposure of VT-11134 was decreased 23% for Cmax (GMR, 0.77; 90%CI [0.239, 1.31]) and unchanged for AUC0-last (GMR, 1.02; 90%CI [0.701, 1.33]). Neither VT-1598 nor VT-11134 were detected in urine. No serious adverse events (AEs) or AEs leading to early termination were observed. The safety and PK profiles of VT-1598 support its further clinical development.

MSG-15: Super-Bioavailability Itraconazole Versus Conventional Itraconazole in the Treatment of Endemic Mycoses-A Multicenter, Open-Label, Randomized Comparative Trial

Background

Invasive fungal disease caused by dimorphic fungi is associated with significant morbidity and mortality. Super-bioavailability itraconazole (SUBA-itra) is a novel antifungal agent with pharmacokinetic advantages over currently available formulations. In this prospective comparative study, we report the outcomes of patients with endemic fungal infections (histoplasmosis, blastomycosis, coccidioidomycosis, and sporotrichosis).

Methods

This open-label randomized trial evaluated the efficacy, safety, and pharmacokinetics SUBA-itra compared with conventional itraconazole (c-itra) treatment for endemic fungal infections. An independent data review committee determined responses on treatment days 42 and 180.

Results

Eighty-eight patients were enrolled for IFD (SUBA-itra, n = 42; c-itra, n = 46) caused by Histoplasma (n = 51), Blastomyces (n = 18), Coccidioides (n = 13), or Sporothrix (n = 6). On day 42, clinical success was observed with SUBA-itra and c-itra on day 42 (in 69% and 67%, respectively, and on day 180 (in 60% and 65%). Patients treated with SUBA-itra exhibited less drug-level variability at days 7 (P = .03) and 14 (P = .06) of randomized treatment. The concentrations of itraconazole and hydroxyitraconazole were comparable between the 2 medications (P = .77 and P = .80, respectively). There was a trend for fewer adverse events (AEs; 74% vs 87%, respectively; P = .18) and serious AEs (10% vs 26%; P = .06) in the SUBA-itra-treated patients than in those receiving c-itra. Serious treatment-emergent AEs were less common in SUBA-itra-treated patients (12% vs 50%, respectively; P < .001).

Conclusions

SUBA-itra was bioequivalent, well tolerated, and efficacious in treating endemic fungi, with a more favorable safety profile than c-itra.

Clinical Trials Registration

NCT03572049.

Endemic mycoses - are we making progress in management?

PURPOSE OF REVIEW

The endemic fungi are a significant cause of morbidity and mortality in effected patients. The range of endemicity for these are expanding with infections observed outside of traditional locations. Enhanced diagnostic and treatment practices may significantly alter patient outcomes.

RECENT FINDINGS

Recently completed clinical trials have focused on an assessment of improving efficacy while minimizing patient toxicity. Practice changing trials have been completed in histoplasmosis showing the utility of a single up-front liposomal amphotericin B dose followed by standard itraconazole dosing. The recent evaluation of several antifungal options including isauvconazole in the treatment of coccidioidomycosis also show promise for additional therapeutic agents. A recently conducted trial has also shown the superiority of amphotericin B therapy over itraconazole in the treatment of talaromycosis.

SUMMARY

The increased range of endemic mycoses coupled with the growing immunocompromised patient population mandates continued investigation of improved diagnostic and therapeutic options. Advances in these areas have led to more rapid diagnosis and more efficacious antifungal therapy.

In Vitro Impact of Fluconazole on Oral Microbial Communities, Bacterial Growth, and Biofilm Formation

Antifungal agents are widely used to specifically eliminate infections by fungal pathogens. However, the specificity of antifungal agents has been challenged by a few studies demonstrating antibacterial inhibitory effects against Mycobacteria and Streptomyces species. Here, we evaluated for the first time the potential effect of fluconazole, the most clinically used antifungal agent, on a human oral microbiota biofilm model. The results showed that biofilm viability on blood and mitis salivarius agar media was increased over time in the presence of fluconazole at clinically relevant concentrations, despite a reduction in biomass. Targeted PCR revealed a higher abundance of Veillonella atypica, Veillonella dispar, and Lactobacillus spp. in the fluconazole-treated samples compared to the control, while Fusobacterium nucleatum was reduced and Streptococcus spp were not significantly affected. Further, we tested the potential impact of fluconazole using single-species models. Our results, using Streptococcus mutans and Streptococcus mitis luciferase reporters, showed that S. mutans planktonic growth was not significantly affected by fluconazole, whereas for S. mitis, planktonic growth, but not biofilm viability, was inhibited at the highest concentration. Fluconazole's effects on S. mitis biofilm biomass were concentration and time dependent. Exposure for 48 h to the highest concentration of fluconazole was associated with S. mitis biofilms with the most increased biomass. Potential growth inhibitory effects were further tested using four non-streptococcal species. Among these, the planktonic growth of both Escherichia coli and Granulicatella adiacens was inhibited by fluconazole. The data indicate bacterial responses to fluconazole that extend to a broader range of bacterial species than previously anticipated from the literature, with the potential to disturb biofilm communities.

Isavuconazole in the Treatment of Chronic Forms of Coccidioidomycosis

Coccidioidomycosis is a fungal infection with a range of clinical manifestations. Currently used antifungal agents exhibit variable efficacy and toxicity profiles that necessitate evaluation of additional therapeutic options. Improvement was observed in the majority of patients treated with isavuconazole, with clinical failures observed only in those with coccidioidal meningitis.

Effect of coccidioidomycosis prophylaxis in selecting non-Candida albicans species amongst solid organ transplant recipients in Arizona

BACKGROUND

Invasive candidiasis carries an increased risk of morbidity and mortality. The rates of non-albicans Candida species (NAC) infections are on the rise secondary to frequent azole antifungal use. NAC incidence and risk amongst solid organ transplant (SOT) recipients in Arizona receiving prolonged azole course for coccidioidomycosis prophylaxis have not been well elucidated.

METHODS

We retrospectively evaluated SOT recipients hospitalised between 2017 and 2021 with a positive Candida spp. culture.

RESULTS

There were 66 SOT recipients with 74 hospitalisations and 79 Candida spp. isolates. The median age was 59 (IQR 45-66), 68% were male, 58% were non-Hispanic White, and the most common SOT 38/74 (51%) was a liver transplant. Median time from transplant to the identification of any NAC (infection or colonisation) was significantly shorter, 8 months (IQR 3-78) vs 128 months (IQR 10-282) for Candida albicans isolates, p = .03. Prior use of azoles was significantly higher in NAC-associated post-transplant colonisation and invasive disease hospitalisations (83%) than in those with C. albicans (17%), p < .001. There were 59 hospitalisations with invasive disease, with the majority having NAC isolates of 49 (83%).

CONCLUSION

The universal azole prophylaxis has reduced the incidence of coccidioidomycosis complications amongst SOT recipients in Arizona; however, there is an increased risk of developing NAC colonisation and infections, which can complicate the care of the SOT recipients with invasive candidiasis. Future studies are needed to investigate methods of reducing the risk of NAC infections whilst preventing coccidioidomycosis amongst SOT recipients.

Can fluconazole be used for inpatient re-treatment of coccidioidomycosis among patients with past fluconazole exposures?

BACKGROUND

Coccidioides spp. may cause significant disease requiring hospitalisation, but optimal antifungal therapy among inpatients following outpatient fluconazole exposures is unknown.

OBJECTIVES

The objective of this study is to describe the effectiveness of fluconazole among patients hospitalised for coccidioidomycosis despite recent outpatient fluconazole treatment.

PATIENTS/METHODS

Patients were admitted to an academic medical center in Phoenix, Arizona from 1 January 2013 through 31 December 2020 for coccidioidomycosis following at least 30 days of outpatient treatment and re-initiation of fluconazole upon admission. The primary outcome was the proportion of patients with an improved response per the change in the modified Mycosis Study Group (MSG) score (a composite of symptoms, serology and radiographic findings) and clinician impressions.

RESULTS

Sixty-seven patients were included, with most (54%) admitted to the intensive care unit. Meningitis was the most common infectious presentation (55%), 17 patients (25%) had multiple infection sites, and 23 (34%) were culture-positive for Coccidioides. Upon admission, the median (IQR) MSG score was 11 (9-14), which dropped to 4 (1-7) at end of therapy or last follow-up. Overall, after initiation of fluconazole therapy at a median daily dose of 800 mg, 48 patients (72%) improved in overall status, 10 (15%) showed stable disease and 9 (13%) were unresponsive. Improved response rates were high across all infection sites, including meningitis (68%) and bone infection (71%). There was no significant difference in response rates between patients with and without reported outpatient fluconazole nonadherence.

CONCLUSIONS

The majority of patients admitted to the hospital for coccidioidomycosis appeared responsive to fluconazole therapy despite past outpatient exposures.

Safety of triazole antifungals: a pharmacovigilance study from 2004 to 2021 based on FAERS

Background

Triazole antifungals are widely used as broad-spectrum antifungal activity; however, there are many undetected and unreported adverse events (AEs).

Methods

Data from the Food and Drug Administration Adverse Event Reporting System (FAERS) from the first quarter (Q1) of 2004 to the third quarter (Q3) of 2021 were selected for disproportionality analysis to assess the connection between antifungal triazoles, and AEs and important medical events (IMEs).

Results

A total of 22,566 records associated with triazole antifungals were identified, with 9584 triazole antifungal-IME pairs. The following system organ classes (SOCs) appeared as significant signals: 'Endocrine disorders' [reported odds ratio (ROR) = 167.94], 'Metabolism and nutrition disorders' (ROR = 46.30), and 'Skin and subcutaneous tissue disorders' (ROR = 21.37). Strong signals were observed with respiratory failure, rash, hepatic function abnormal, and hypokalemia. Uncommon security signals included a change in the QT interval, neurotoxicity, pseudoaldosteronism, and hallucinations.

Conclusion

Various triazole antifungals cause AEs of different types and intensities of association. Our results are broadly consistent with prescribing information and previous studies; however, additional pharmacoepidemiological studies are required to verify AEs with modest incidence but high signal.

Plain Language Summary

A study on the adverse effects of triazole antifungals Introduction: The triazole antifungals we studied include fluconazole, itraconazole, voriconazole, posaconazole, and isavuconazole. Triazole antifungals are widely used as broad-spectrum antifungals; however, there are many undetected and unreported adverse events (AEs).Materials and Methods: The Food and Drug Administration Adverse Event Reporting System (FAERS) database contains AEs reported to the FDA by different countries regarding post-marketing drugs. Through the FAERS database, we retrieved a total of 22,566 AE reports related to triazole antifungals. We not only counted information about patients' gender, age, weight, reporting country, outcome indicators, and indications but also analyzed the system organ classes (SOCs) of AEs, and the number of reported drug-related AEs and the degree of relevance.Results: We found a total of 22,566 records related to triazole antifungal agents, of which 9584 reports made important medical events (IMEs) about triazole antifungal agents, which are serious AEs. The following SOCs appear as important signals: 'endocrine disorders', 'metabolic and nutritional disorders', and 'skin and subcutaneous tissue disorders'. Triazole antifungals produce AEs, such as respiratory failure, rash, hepatic function abnormal, and hypokalemia. They also produce uncommon AEs, including changes in the QT interval, neurotoxicity, pseudoaldosteronism, and hallucinations.Conclusion: By analyzing data from the FAERS database, we identified more AEs associated with these five triazole antifungals than were indicated in the instructions and our findings provide additional insight into triazole-related AEs to inform clinicians before and during treatment.

Follow-Up of Surgical or Nonsurgical Patients with Pulmonary Cryptococcosis: A Real-World Study

Background

Surgical and medical treatments are applied to pulmonary cryptococcosis (PC) in the real world, while the prognosis of different therapies is uncertain. This study investigated diagnosis, real-world therapy, follow-up outcomes, and prognosis factors, aiming to deepen our understanding of PC.

Methods

Patients pathologically diagnosed with PC were retrospectively reviewed and followed up. Further comparisons and subgroup analyses were conducted in surgical and nonsurgical treatment individuals. Univariable and multivariable logistic regression methods were used to explore the risk factors associated with treatment failure.

Results

One hundred and sixty-three patients were included in this study, of whom 92 underwent surgical removal of VATS or open lung surgery (68 of them received postoperative antifungal treatment) and 71 got antifungal drugs only. Compared with nonsurgical patients, surgical patients were more immunocompetent (73 [79.3%] cases vs 33 [46.5%]), showed milder symptoms and more limited pulmonary lesions. Although they had instant treatment response owing to lesions resection, there is no significant advantage in the rate of treatment failure. Multivariable regression showed independent predictive factors associated with treatment failure were polymorphonuclear (PMN)>6.30*10⁹/L, albumin (Alb) <40g/L and antifungal dosage <400mg/d. Further analysis among patients with different immune statuses or symptoms demonstrated that sufficient antifungal dosage could reduce the rate of treatment failure.

Conclusion

PC showed variable and nonspecific clinical features. PC patients with limited nodules/masses and mild symptoms often led to misdiagnosis and unnecessary lung resections. The potential risk factors including higher PMN and hypoalbuminemia could help clinicians to identify PC patients with poor treatment efficiency at an early stage. To note, sufficient antifungal dosage may improve the treatment outcomes.

Controversies in the Management of Central Nervous System Coccidioidomycosis

Central nervous system infection with Coccidioides spp is fatal if untreated, and complications occur even when therapy is directed by experienced clinicians. We convened a panel of clinicians experienced in the management of coccidioidal meningitis to summarize current controversies and provide consensus for the management of this difficult infection.

Current Landscape of Coccidioidomycosis

Coccidioidomycosis, also known as Valley fever, is an endemic fungal infection commonly found in the southwestern parts of the United States. However, the disease has seen an increase in both in its area of residency and its prevalence. This review compiles some of the latest information on the epidemiology, current and in-development pharmaceutical approaches to treat the disease, trends and projections, diagnostic concerns, and the overlapping dynamics of coccidioidomycosis and COVID-19, including in special populations. This review provides an overview of the current diagnostic and therapeutic strategies and identifies areas of future development.

Use of Modeling and Simulation to Predict the Influence of Triazole Antifungal Agents on the Pharmacokinetics of Crizotinib

Crizotinib is used for the treatment of c-ros oncogene 1-positive advanced non-small-cell lung cancer. Triazole antifungal agents are widely used for invasive fungal infections in clinical practice. To predict the potential influence of different triazoles (voriconazole, fluconazole, and itraconazole) on the pharmacokinetics of crizotinib by modeling and simulation the physiologically based pharmacokinetic models were established and validated in virtual cancer subjects through Simcyp software based on the essential physicochemical properties and pharmacokinetic data collected. The validated physiologically based pharmacokinetic models were applied to predict the drug-drug interactions between crizotinib and different triazoles (voriconazole, fluconazole, or itraconazole) in patients with cancer. Crizotinib and triazole antifungal agents were administered orally. The predicted plasma concentration vs time profiles of crizotinib, voriconazole, fluconazole, and itraconazole showed good agreement with observed, respectively. The geometric mean area under the plasma concentration-time curve (AUC) of crizotinib was increased by 84%, 58%, and 79% when coadministered with voriconazole, fluconazole, or itraconazole at multiple doses, respectively. The drug-drug interaction results showed increased pharmacokinetic exposure (maximum plasma concentration and area under the plasma concentration-time curve) of crizotinib when coadministrated with different triazoles (voriconazole > itraconazole > fluconazole). Among the 3 triazoles, voriconazole exhibited the most significant influence on the pharmacokinetic exposure of crizotinib. In clinic, adverse drug reactions and toxicity related to crizotinib should be carefully monitored, and therapeutic drug monitoring for crizotinib is recommended to guide dosing and optimize treatment when coadministered with voriconazole, fluconazole, or itraconazole.

Novel Antifungals for the Treatment of Vulvovaginal Candidiasis: Where Are We?

Vulvovaginal candidiasis (VVC) is a common health-related issue and the second most common cause of vaginitis. Previously, azole antifungals were the mainstay of VVC treatment. Additionally, boric acid and nystatin have been used topically for management of VVC. Despite being effective and well tolerated by most patients, the use of azoles may be limited in some cases. Currently, two new antifungal agents have received US Food and Drug Administration approval for use in the management of VVC. In this article, we briefly review treatment regimens used for the management of VVC over the past decade, the newly approved agents and their possible clinical application, and future treatment considerations.

A randomized, double-blind, placebo-controlled clinical trial of fluconazole as early empiric treatment of coccidioidomycosis pneumonia (Valley Fever) in adults presenting with community-acquired pneumonia in endemic areas (FLEET-Valley Fever)

Introduction

Coccidioidomycosis is a fungal infection endemic in the southwestern United States (US). Primary pulmonary coccidioidomycosis (PPC) is a leading cause of community-acquired pneumonia (CAP) in this region, although its diagnosis is often delayed, leading to lag in antifungal treatment and subsequent morbidity. The impact of early empiric antifungal therapy as part of treatment for CAP in endemic areas on clinical outcomes is unknown.

Methods

Phase IV randomized, double-blind, placebo-controlled trial in individuals aged 18 years or older with CAP who met all eligibility criteria in Coccidioides endemic regions in the US. Eligible participants with CAP were randomized to receive either fluconazole (400 mg daily) or matching placebo for 42 days and were subsequently monitored for clinical resolution of their illness.

Objectives

The primary objective was to assess the clinical response of early empiric antifungal therapy with fluconazole through Day 22 in subjects with PPC who were adherent to the study intervention. Secondary objectives included: assessments of the impact of early empiric antifungal therapy with fluconazole through Day 22 and 43 in subjects with PPC regardless of adherence, comparisons of the clinical response and its individual components over time by treatment group in subjects with PPC, assessments of days lost from work or school, hospitalization, and all-cause mortality.

Discussion

This trial was halted early due to slow enrollment (72 participants in one year, 33 received fluconazole and 39 received placebo). Of those enrolled, eight (11%) met the study definition of PPC. The study design and challenges are discussed.

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Clinical impact of early antifungal therapy for pneumonia in Coccidioides endemic regions is unknown.

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We designed a phase IV trial in adults with community-acquired pneumonia in regions endemic for Coccidioides.

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Trial was halted early due to slow enrollment and low prevalence of coccidioidomycosis in the enrollment population.

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Lost to follow-up and treatment discontinuation were common in this trial.

Coccidioidomycosis

Coccidioidomycosis, caused by the dimorphic pathogenic fungi Coccidioides immitis and Coccidioides posadassi, is endemic to the southwestern United states and Central and South America. The incidence of coccidioidomycosis continues to increase. Coccidioidomycosis is typically a self-limiting influenza-like respiratory illness; however, it can lead to disseminated disease outside of the lungs. Not all nondisseminated cases require therapy, but antifungal therapy is typically beneficial requiring treatment ranging from months to lifelong. Clinical factors related to treatment decisions include severity of symptoms, radiography, coccidioidomycosis serologic results, and concurrent medical problems including immunosuppression. This review summarizes the epidemiology, clinical manifestations, and treatment options.

Successful Treatment of Cryptococcal Meningitis and Cryptococcoma with Isavuconazole in a Patient Living with HIV

We describe the successful use of isavuconazole for treatment of an HIV-positive patient with cryptococcal meningitis following induction therapy with liposomal amphotericin B and flucytosine. Because the Cryptococcus neoformans isolate from cerebrospinal fluid had a borderline minimum inhibitory concentration of 8 mg/L, initial consolidation therapy was given with a daily dose of fluconazole 1200 mg based on area under the curve to minimum inhibitory concentration modelling data. Toxicity, and the radiological emergence of a cryptococcoma in the setting of immune reconstitution inflammatory syndrome, prompted a therapeutic switch to isavuconazole. Subsequent imaging after 19 weeks of isavuconazole shows a significant reduction in cryptococcoma size from 11 mm to complete resolution. The patient remains well after 210 days of therapy with a view to completion of treatment after 1 year.

Utilization of potentially inappropriate medication and risk of adverse drug events among older adults with chronic renal insufficiency: a population-wide cohort study

BACKGROUND

The use of potentially inappropriate medication (PIM) in population of older adults may result in adverse drug events (ADE) already after short term exposure, especially when it is prescribed to patients with chronic kidney disease (CKD). In order to limit ADE in the treatment of older adults PIM lists have been constructed as a source of information for healthcare professionals. The aim of this study was to estimate the utilization of PIM and incidence of ADE in older adults (≥70 years) with CKD.

METHODS

We conducted a retrospective population-wide cohort study including patients from Lower Austria who were 70 years or older and diagnosed with CKD in the period from 2008 to 2011. Utilization of PIM was estimated from prescriptions filled by target population. We estimated risks of hospitalization due to ADE within 30 days after incident PIM prescription and compared them to a PIM-free control group by using marginal structural models (MSM).

RESULTS

We identified 11,547 patients (women: 50.6%, median age in 2008: 78 years) who fulfilled the inclusion criteria. In total 24.7 and 8.1% of all prescriptions from that period contained a medication with a substance listed in the EU (7)-PIM and AT-PIM list, respectively. Proton pump inhibitors and Ginkgo biloba were the most often prescribed PIMs in this population. 94.6 and 79.3% patients filled at least one EU(7)-PIM and AT-PIM prescription, respectively. Despite the relatively high utilization of PIM there was only a low incidence of clinically relevant ADE. No event type exceeded the threshold level of 1% in the analysis of risks of ADE after filling a prescription for PIM. Nevertheless, MSM analysis showed an increased risk for 11 drugs and reduced risk for 4 drugs.

CONCLUSIONS

PIM prescription was common among older adults with CKD, however, only a small number of these drugs eventually led to hospitalization due to ADE within 30 days after incident PIM was filled. In the absence of a clinically important PIM-related increase in risk, an assessment of potential ADE severity to a PIM list by using a warning score system seems prudent.

Treatment for Early, Uncomplicated Coccidioidomycosis: What Is Success?

The care of primary pulmonary coccidioidomycosis remains challenging. Such infections produce a variety of signs, symptoms, and serologic responses that cause morbidity in patients and concern in treating clinicians for the possibility of extrapulmonary dissemination. Illness may be due to ongoing fungal growth that produces acute inflammatory responses, resulting in tissue damage and necrosis, and for this, administering an antifungal drug may be of benefit. In contrast, convalescence may be prolonged by other immunologic reactions to infection, even after fungal replication has been arrested, and in those situations, antifungal therapy is unlikely to yield clinical improvement. In this presentation, we discuss what findings are clinical indicators of fungal growth and what other sequelae are not. Understanding these differences provides a rational management strategy for deciding when to continue, discontinue, or reinstitute antifungal treatments.

Coccidioidomycosis: Changing Concepts and Knowledge Gaps

Although first described more than 120 years ago, much remains unknown about coccidioidomycosis. In this review, new information that has led to changing concepts will be reviewed and remaining gaps in our knowledge will be discussed. In particular, new ideas regarding ecology and epidemiology, problems and promises of diagnosis, controversies over management, and the possibility of a vaccine will be covered.

Voriconazole enhances UV-induced DNA damage by inhibiting catalase and promoting oxidative stress

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer and is associated with cumulative UV exposure. Studies have shown that prolonged voriconazole use promotes cSCC formation; however, the biological mechanisms responsible for the increased incidence remain unclear. Here, we show that voriconazole directly increases oxidative stress in human keratinocytes and promotes UV-induced DNA damage as determined by comet assay, 8-oxoguanine immunofluorescence and mass spectrometry. Voriconazole treatment of human keratinocytes potentiates UV-induced apoptosis and activation of the p38 MAP kinase and 53BP1 UV stress response pathways. The p38 MAP kinase activation promoted by voriconazole exposure can be mitigated by pretreating keratinocytes with N-acetylcysteine. Voriconazole increases oxidative stress in keratinocytes by directly inhibiting catalase leading to lower intracellular NADPH levels and the triazole moieties in voriconazole are critical for inhibiting catalase. Furthermore, voriconazole is shown to promote UV-induced dysplasia in an in vivo model. Together, these data demonstrate that voriconazole potentiates oxidative stress in UV-irradiated keratinocytes through catalase inhibition. Use of antioxidants may mitigate the pro-oncogenic effects of voriconazole.

Resorbable Beads Provide Extended Release of Antifungal Medication: In Vitro and In Vivo Analyses

Fungal osteomyelitis has been difficult to treat, with first-line treatments consisting of implant excision, radical debridement, and local release of high-dose antifungal agents. Locally impregnated antifungal beads are another popular treatment option. This study aimed to develop biodegradable antifungal-agent-loaded Poly(d,l-lactide-co-glycolide) (PLGA) beads and evaluate the in vitro/in vivo release patterns of amphotericin B and fluconazole from the beads. Beads of different sizes were formed using a compression-molding method, and their morphology was evaluated via scanning electron microscopy. Intrabead incorporation of antifungal agents was evaluated via Fourier-transform infrared spectroscopy, and in vitro fluconazole liberation curves of PLGA beads were inspected via high-performance liquid chromatography. When we implanted the drug-incorporated beads into the bone cavity of rabbits, we found that a high level of fluconazole (beyond the minimum therapeutic concentration [MTC]) was released for more than 49 d in vivo. Our results indicate that compression-molded PLGA/fluconazole beads have potential applications in treating bone infections.

The Rise of Coccidioides: Forces Against the Dust Devil Unleashed

Coccidioidomycosis (Valley fever) is a fungal disease caused by the inhalation of Coccidioides posadasii or C. immitis. This neglected disease occurs in the desert areas of the western United States, most notably in California and Arizona, where infections continue to rise. Clinically, coccidioidomycosis ranges from asymptomatic to severe pulmonary disease and can disseminate to the brain, skin, bones, and elsewhere. New estimates suggest as many as 350,000 new cases of coccidioidomycosis occur in the United States each year. Thus, there is an urgent need for the development of a vaccine and new therapeutic drugs against Coccidioides infection. In this review, we discuss the battle against Coccidioides including the development of potential vaccines, the quest for new therapeutic drugs, and our current understanding of the protective host immune response to Coccidioides infection.

Minimum Inhibitory Concentration Distribution of Fluconazole against Cryptococcus Species and the Fluconazole Exposure Prediction Model

BACKGROUND

Fluconazole is lifesaving for treatment and prevention of cryptococcosis; however, optimal dosing is unknown. Initial fluconazole doses of 100mg to 2000mg/day have been used. Prevalence of fluconazole non-susceptible Cryptococcus is increasing over time, risking the efficacy of long-established standard dosing. Based on current minimum inhibitory concentration (MIC) distribution, we modeled fluconazole concentration and area under the curve (AUC) relative to MIC to propose a rational fluconazole dosing strategy.

METHODS

First, we conducted a systematic review using MEDLINE database for reports of fluconazole MIC distribution against clinical Cryptococcus isolates. Second, we utilized fluconazole concentrations from 92 Ugandans who received fluconazole 800mg/day coupled with fluconazole's known pharmacokinetics to predict plasma fluconazole concentrations for doses ranging from 100mg to 2000mg via linear regression. Third, the fluconazole AUC above MIC ratio were calculated using Monte Carlo simulation and using the MIC distribution elucidated during the systemic review.

RESULTS

We summarized 21 studies with 11,049 clinical Cryptococcus isolates. MICs were normally distributed with geometric mean of 3.4 μg/mL, median (MIC50) of 4 μg/mL, and 90th percentile (MIC90) of 16 μg/mL. The median MIC50 trended upwards from 4 μg/mL in 2000-2012 to 8 μg/mL in 2014-2018. Predicted sub-therapeutic fluconazole concentrations (below MIC) would occur in 40% with 100mg, 21% with 200mg, and 9% with 400mg. AUC/MIC ratio >100 would occur in 53% for 400mg, 74% for 800mg, 83% for 1200mg, and 88% for 1600mg.

CONCLUSIONS

Currently recommended fluconazole doses may be inadequate for cryptococcosis. Further clinical studies are needed for rational fluconazole dose selection.