scholarly journals In Vitro Activity of Manogepix against Multidrug-Resistant and Panresistant Candida auris from the New York Outbreak

2020 ◽  
Vol 64 (11) ◽  
Author(s):  
YanChun Zhu ◽  
Shannon Kilburn ◽  
Mili Kapoor ◽  
Sudha Chaturvedi ◽  
Karen Joy Shaw ◽  
...  

ABSTRACT An ongoing Candida auris outbreak in the New York metropolitan area is the largest recorded to date in North America. Laboratory surveillance revealed NY C. auris isolates are resistant to fluconazole, with variable resistance to other currently used broad-spectrum antifungal drugs, and that several isolates are panresistant. Thus, there is an urgent need for new drugs with a novel mechanism of action to combat the resistance challenge. Manogepix (MGX) is a first-in-class agent that targets the fungal Gwt1 enzyme. The prodrug fosmanogepix is currently in phase 2 clinical development for the treatment of fungal infections. We evaluated the susceptibility of 200 New York C. auris isolates to MGX and 10 comparator drugs using CLSI methodology. MGX demonstrated lower MICs than comparators (MIC50 and MIC90, 0.03 mg/liter; range, 0.004 to 0.06 mg/liter). The local epidemiological cutoff value (ECV) for MGX indicated all C. auris isolates were within the population of wild-type (WT) strains; 0.06 mg/liter defines the upper limit of wild type (UL-WT). MGX was 8- to 32-fold more active than the echinocandins, 16- to 64-fold more active than the azoles, and 64-fold more active than amphotericin B. No differences were found in the MGX or comparators’ MIC50, MIC90, or geometric mean (GM) values when subsets of clinical, surveillance, and environmental isolates were evaluated. The range of MGX MIC values for six C. auris panresistant isolates was 0.008 to 0.015 mg/liter, and the median and mode MIC values were 0.015 mg/liter, demonstrating that MGX retains activity against these isolates. These data support further clinical evaluation of fosmanogepix for the treatment of C. auris infections, including highly resistant isolates.

2020 ◽  
Author(s):  
YanChun Zhu ◽  
Shannon Kilburn ◽  
Mili Kapoor ◽  
Sudha Chaturvedi ◽  
Karen Joy Shaw ◽  
...  

ABSTRACTAn ongoing Candida auris outbreak in the New York metropolitan area is the largest recorded to date in North America. Laboratory surveillance revealed NY C. auris isolates are resistant to fluconazole, with variable resistance to other currently used broad-spectrum antifungal drugs, and that several isolates are pan-resistant. Thus, there is an urgent need for new drugs with a novel mechanism of action to combat the resistance challenge. Manogepix (MGX) is a first-in-class agent that targets the fungal Gwt1 enzyme. The prodrug, fosmanogepix, is currently in Phase 2 clinical development for the treatment of fungal infections. We evaluated the susceptibility of 200 New York C. auris isolates to MGX and 10 comparator drugs using CLSI methodology. MGX demonstrated lower MICs than comparators (MIC50 and MIC90 0.03 mg/L; range 0.004-0.06 mg/L). The MGX epidemiological cutoff value (ECV, 99% cutoff) for the tested C. auris isolates was 0.06 mg/L. MGX was 8-32-fold more active than the echinocandins, 16-64-fold more active than the azoles, and 64-fold more active than amphotericin B. No differences were found in the MGX or comparators’ MIC50, MIC90, or GEOMEAN values when subsets of clinical, surveillance, and environmental isolates were evaluated. The range of MGX MIC values for six C. auris pan-resistant isolates was 0.008-0.015 mg/L, and the median and mode MIC values were 0.015 mg/L, demonstrating that MGX retains activity against these isolates. These data support further clinical evaluation of fosmanogepix for the treatment of C. auris infections, including highly resistant isolates.


2020 ◽  
Vol 64 (4) ◽  
Author(s):  
Brittany O’Brien ◽  
Sudha Chaturvedi ◽  
Vishnu Chaturvedi

ABSTRACT Since 2016, New York hospitals and health care facilities have faced an unprecedented outbreak of the pathogenic yeast Candida auris. We tested over 1,000 C. auris isolates from affected facilities and found high resistance to fluconazole (MIC > 256 mg/liter) and variable resistance to other antifungal drugs. Therefore, we tested if two-drug combinations are effective in vitro against multidrug-resistant C. auris. Broth microdilution antifungal combination plates were custom manufactured by TREK Diagnostic System. We used 100% inhibition endpoints for the drug combination as reported earlier for the intra- and interlaboratory agreements against Candida species. The results were derived from 12,960 readings, for 15 C. auris isolates tested against 864 two-drug antifungal combinations for nine antifungal drugs. Flucytosine (5FC) at 1.0 mg/liter potentiated the most combinations. For nine C. auris isolates resistant to amphotericin B (AMB; MIC ≥ 2.0 mg/liter), AMB-5FC (0.25/1.0 mg/liter) yielded 100% inhibition. Six C. auris isolates resistant to three echinocandins (anidulafungin [AFG], MIC ≥ 4.0 mg/liter; caspofungin [CAS], MIC ≥ 2.0 mg/liter; and micafungin [MFG], MIC ≥ 4.0 mg/liter) were 100% inhibited by AFG-5FC and CAS-5FC (0.0078/1 mg/liter) and MFG-5FC (0.12/1 mg/liter). None of the combinations were effective for C. auris 18-1 and 18-13 (fluconazole [FLC] > 256 mg/liter, 5FC > 32 mg/liter) except MFG-5FC (0.1/0.06 mg/liter). Thirteen isolates with a high voriconazole (VRC) MIC (>2 mg/liter) were 100% inhibited by the VRC-5FC (0.015/1 mg/liter). The simplified two-drug combination susceptibility test format would permit laboratories to provide clinicians and public health experts with additional data to manage multidrug-resistant C. auris.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S654-S654
Author(s):  
Yan Chun Zhu ◽  
Shannon N Kilburn ◽  
Mili Kapoor ◽  
Sudha Chaturvedi ◽  
Karen J Shaw ◽  
...  

Abstract Background An ongoing Candida auris outbreak in the New York metropolitan area is the largest recorded to date in North America. NY C. auris isolates demonstrate resistance to fluconazole and variable resistance to other antifungals. Thus, there is an urgent need for new drugs with a novel mechanism of action to combat the resistance challenge. Manogepix (MGX) is a first-in-class agent that targets the fungal Gwt1 enzyme. The prodrug, fosmanogepix, is in clinical development for the treatment of invasive fungal infections. Methods We evaluated the susceptibility of 200 NY C. auris isolates (2017-2020) to MGX and 10 comparators. Testing was performed using TREK frozen broth microdilution panels for FLC, VRC, ITC, ISA, POS, AFG, CAS, and MFG. MGX MICs were evaluated (CLSI M27-A3 guidelines) using a 50% reduction in fungal growth endpoint at 24 h. MICs were determined by ETEST® at 24 h for AMB and FLC. We defined pan-resistant C. auris as isolates with in vitro resistance to two or more azoles, all echinocandins, and AMB. The epidemiological cutoff values (ECVs, ECOFFs) for MGX were estimated using the Microsoft Excel spreadsheet calculator ECOFFinder. Results MGX demonstrated lower MICs than comparators (MIC50 and MIC90 0.03 mg/L; range 0.004-0.06 mg/L). MGX was 8-32-fold more active that the echinocandins, 16-64-fold more active than the azoles, and 64-fold more active than AMB. No differences were found in the MGX or comparators’ MIC50, MIC90, or GEOMEAN values when subsets of clinical, surveillance, and environmental isolates were evaluated. The range of MGX MIC values for six C. auris pan-resistant isolates was 0.008-0.015 mg/L, and the median and mode MIC values were 0.015 mg/L, demonstrating that MGX retains activity against these isolates. The MGX epidemiological cutoff value (ECV, 99% cutoff) was 0.06 mg/L. Conclusion MGX MICs were low against C. auris isolates including those with variable patterns of resistance to AMB, azoles, and echinocandins. In addition, MGX retained potent activity against six pan-resistant isolates. These data support the continued clinical evaluation of fosmanogepix for the treatment of C. auris infections, including highly resistant isolates. Disclosures Karen J. Shaw, PhD, Amplyx (Consultant)Forge Therapeutics (Consultant) Vishnu Chaturvedi, PhD, Amplyx (Grant/Research Support)


2019 ◽  
Vol 63 (12) ◽  
Author(s):  
A. L. Bidaud ◽  
F. Botterel ◽  
A. Chowdhary ◽  
E. Dannaoui

ABSTRACT Candida auris is an emerging, multidrug-resistant pathogen responsible for invasive hospital-acquired infections. Flucytosine is an effective anti-Candida species drug, but which cannot be used as a monotherapy because of the risk of development of resistant mutants during treatment. It is, therefore, noteworthy to test possible combinations with flucytosine that may have a synergistic interaction. In this study, we determined the in vitro interaction between flucytosine and amphotericin B, micafungin, or voriconazole. These combinations have been tested against 15 C. auris isolates. The MIC ranges (geometric mean [Gmean]) of flucytosine, amphotericin B, micafungin, and voriconazole were 0.125 to 1 μg/ml (0.42 μg/ml), 0.25 to 1 μg/ml (0.66 μg/ml), 0.125 to 0.5 μg/ml (0.3 μg/ml), and 0.03 to 4 μg/ml (1.05 μg/ml), respectively. When tested in combination, indifferent interactions were mostly observed with fractional inhibitory concentration index values from 0.5 to 1, 0.31 to 1.01, and 0.5 to 1.06 for the combinations of flucytosine with amphotericin B, micafungin, and voriconazole, respectively. A synergy was observed for the strain CBS 10913 from Japan. No antagonism was observed for any combination. The combination of flucytosine with amphotericin B or micafungin may be relevant for the treatment of C. auris infections.


2019 ◽  
Vol 64 (3) ◽  
Author(s):  
Maiken Cavling Arendrup ◽  
Karin Meinike Jørgensen ◽  
Rasmus Krøger Hare ◽  
Anuradha Chowdhary

ABSTRACT Ibrexafungerp (SCY-078) is a novel first-in-class antifungal agent targeting glucan synthase. Candida auris is an emerging multidrug-resistant species that has caused outbreaks on five continents. We investigated the in vitro activity of ibrexafungerp against C. auris by applying EUCAST E.Def 7.3.1 methodology. C. albicans and C. glabrata, as well as anidulafungin, micafungin, amphotericin B, fluconazole, voriconazole, and isavuconazole, were included as comparators. Three C. auris reference strains (CBS12372, CBS12373, and CBS10913) and 122 C. auris, 16 C. albicans, and 16 C. glabrata isolates were evaluated. C. albicans ATCC 64548, C. parapsilosis ATCC 22019, and C. krusei ATCC 6258 served as quality control strains. Echinocandin-resistant isolates were fks sequenced. MIC ranges and modal MIC and MIC50 values were determined. Wild-type upper limits (the upper MIC value where the wild-type distribution ends) were determined according to EUCAST principles for setting ECOFFs. Nine repetitions of three QC strains and MICs for C. albicans and C. glabrata yielded narrow MIC ranges with modal MICs in agreement with established EUCAST modal MICs, confirming a robust test performance. The ibrexafungerp MICs against C. auris isolates displayed a Gaussian distribution with a modal MIC (range) of 0.5 mg/liter (0.06 to 2 mg/liter), suggesting uniform susceptibility. Of 122 isolates, 8 were echinocandin resistant and harbored the S639F Fks1 alteration. All but one were fluconazole resistant, and the MIC distributions for voriconazole and isavuconazole were multimodal confirming variable susceptibility. Ibrexafungerp demonstrated promising activity against C. auris, including isolates resistant to echinocandins and/or other agents. The MICs were similar to those reported for the Clinical and Laboratory Standards Institute method, suggesting that a common clinical breakpoint may be appropriate.


2019 ◽  
Author(s):  
Brittany O’Brien ◽  
Sudha Chaturvedi ◽  
Vishnu Chaturvedi

AbstractSince 2016, New York hospitals and healthcare facilities have faced an unprecedented outbreak of pathogenic yeast Candida auris. We tested over one thousand C. auris isolates from affected facilities and found high-resistance to fluconazole (FLC, MIC50>256 mg/L), and variable resistance to other antifungal drugs. Therefore, we evaluated if two-drug combinations are effective in vitro against multidrug-resistant C. auris. Broth micro-dilution (BMD) plates were custom-designed, and quality controlled by TREK Diagnostic System. We used MIC100 endpoints for the drug combination readings as reported earlier for the intra- and inter-laboratory agreements against Candida species and Aspergillus fumigatus. The study results were derived from 12,960 MIC100 readings, for fifteen C. auris isolates tested against 864 possible two-drug antifungal combinations for nine antifungal drugs. Flucytosine (5FC) at 1.0 mg/L potentiated the most successful combinations with other drugs. Micafungin (MFG), Anidulafungin (AFG), Caspofungin (CAS) at individual concentrations of 0.25 mg/L in combination with 5FC (1.0 mg/L) yielded MIC100 for 14, 13, and 12 of 15 C. auris test isolates. AMB / 5FC (0.25/1.0 mg/L) yielded MIC100 for 13 isolates. None of the combinations were effective for C. auris 18-1, which tested resistant against FLC and 5FC, except POS/5FC (0.12/1.0 mg/L). The simplified two-drug combination susceptibility test format would permit laboratories to provide clinicians and public health experts with additional data to deal with multidrug-resistant C. auris.


2021 ◽  
Vol 14 (5) ◽  
pp. 488
Author(s):  
Lucie Peyclit ◽  
Hanane Yousfi ◽  
Jean-Marc Rolain ◽  
Fadi Bittar

Immunodepression, whether due to HIV infection or organ transplantation, has increased human vulnerability to fungal infections. These conditions have created an optimal environment for the emergence of opportunistic infections, which is concomitant to the increase in antifungal resistance. The use of conventional antifungal drugs as azoles and polyenes can lead to clinical failure, particularly in immunocompromised individuals. Difficulties related to treating fungal infections combined with the time required to develop new drugs, require urgent consideration of other therapeutic alternatives. Drug repurposing is one of the most promising and rapid solutions that the scientific and medical community can turn to, with low costs and safety advantages. To treat life-threatening resistant fungal infections, drug repurposing has led to the consideration of well-known and potential molecules as a last-line therapy. The aim of this review is to provide a summary of current antifungal compounds and their main resistance mechanisms, following by an overview of the antifungal activity of non-traditional antimicrobial drugs. We provide their eventual mechanisms of action and the synergistic combinations that improve the activity of current antifungal treatments. Finally, we discuss drug repurposing for the main emerging multidrug resistant (MDR) fungus, including the Candida auris, Aspergillus or Cryptococcus species.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S576-S577
Author(s):  
Brittany O’Brien ◽  
Sudha Chaturvedi ◽  
Vishnu Chaturvedi

Abstract Background Candida auris outbreak continues unabated in New York with the current case counts exceeding 300 patients. We used a modification of standard CLSI broth microdilution method (BMD) if two-drug combinations are efficacious against C. auris isolates with high-resistance to fluconazole (FZ, MIC50 >256 mg/L), and variable resistance to other broad-spectrum antifungal drugs. Methods BMD plates were custom-designed and quality controlled by TREK Diagnostic System. The combination tests of 15 drug-resistant C. auris involved microtiter wells with the initial 144 two-drug combinations and their two-fold dilutions (1/2–1/32) to get 864 two-drug combinations finally. We utilized MIC100 endpoints for the drug combination readings as reported earlier for the intra- and inter-laboratory agreements obtained against Candida species and Aspergillus fumigatus (Antimicrob Agents Chemother. 2015. 59:1759–1766). We also tested minimum fungicidal concentrations (MFC). Results We tested all possible 864 two-drug antifungal combinations for nine antifungal drugs in use to yield 12,960 MIC100 readings, and MFC readings for 15 C. auris isolates. Flucytosine (FLC) at 2.0 mg/L potentiated most successful combinations with other drugs. Micafungin (MFG), Anidulafungin (AFG), Caspofungin (CAS) at individual concentrations of 0.25 mg/L combined well with FLC (2.0 mg/L) to yield MIC100 for 14, 13, and 12 of 15 C. auris isolates tested, respectively. MFG/FLC combination was also fungicidal for 4 of 15 isolates. AMB / FLC (0.25/1.0 mg/L) yielded MIC100 for 13 isolates and MFC for three test isolates. Posaconazole (POS), and Isavuconazole (ISA) and Voriconazole (VRC) also combined well with FLC (0.25/2.0 mg/L) to yield MIC100 for 12, 13, and 13 isolates, respectively. POS/FLC combination was fungicidal for three isolates. Conclusion We identified seven two drug-combinations of antifungals efficacious against drug-resistant C. auris strains. The modified BMD combination susceptibility testing could be used by the clinical laboratories to assist providers with the selection of optimal treatment for C. auris candidemia. Disclosures All authors: No reported disclosures.


2018 ◽  
Vol 62 (5) ◽  
Author(s):  
Cristina Lazzarini ◽  
Krupanandan Haranahalli ◽  
Robert Rieger ◽  
Hari Krishna Ananthula ◽  
Pankaj B. Desai ◽  
...  

ABSTRACTThe incidence of invasive fungal infections has risen dramatically in recent decades. Current antifungal drugs are either toxic, likely to interact with other drugs, have a narrow spectrum of activity, or induce fungal resistance. Hence, there is a great need for new antifungals, possibly with novel mechanisms of action. Previously our group reported an acylhydrazone called BHBM that targeted the sphingolipid pathway and showed strong antifungal activity against several fungi. In this study, we screened 19 derivatives of BHBM. Three out of 19 derivatives were highly active againstCryptococcus neoformansin vitroand had low toxicity in mammalian cells. In particular, one of them, called D13, had a high selectivity index and showed better activity in an animal model of cryptococcosis, candidiasis, and pulmonary aspergillosis. D13 also displayed suitable pharmacokinetic properties and was able to pass through the blood-brain barrier. These results suggest that acylhydrazones are promising molecules for the research and development of new antifungal agents.


2019 ◽  
Vol 63 (4) ◽  
Author(s):  
G. Tetz ◽  
M. Collins ◽  
D. Vikina ◽  
V. Tetz

ABSTRACT An urgent need exists for new antifungal compounds to treat fungal infections in immunocompromised patients. The aim of the current study was to investigate the potency of a novel antifungal compound, MYC-053, against the emerging yeast and yeast-like pathogens Candida glabrata, Candida auris, Cryptococcus neoformans, and Pneumocystis species. MYC-053 was equally effective against the susceptible control strains, clinical isolates, and resistant strains, with MICs of 0.125 to 4.0 μg/ml. Notably, unlike other antifungals such as azoles, polyenes, and echinocandins, MYC-053 was effective against Pneumocystis isolates, therefore being the only synthetic antifungal that may potentially be used against Pneumocystis spp., Candida spp., and Cryptococcus spp. MYC-053 was highly effective against preformed 48-h-old C. glabrata and C. neoformans biofilms, with minimal biofilm eradication concentrations equal to 1 to 4 times the MIC. Together, these data indicated that MYC-053 may be developed into a promising antifungal agent for the treatment and prevention of invasive fungal infections caused by yeasts and yeast-like fungi.


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