Update on New Antifungals Grand Rounds Jack D. Sobel, M.D. Professor of Medicine Wayne State University School of Medicine Detroit, MI
A 74-year-old male is admitted with a one day history of fever, chills and rigors.  He also reports nausea, vomiting but denies any urinary or respiratory symptoms.  He is a Type I, severe diabetic on a moderately high dose of insulin, whose control has been poor. Past medical history is positive for two episodes of myocardial infarction, coronary angioplasty ~2002, moderate intermittent claudication and a mixed sensory-motor peripheral neuropathy.  Hypertension for approximately 20 years.
In the E.M. Department, he was found to be moderately dehydrated, temperature 103.2°F, pulse 128/m, BP 110/60, but was lucid and fully orientated.  JVP not elevated, lungs clear to auscultation and CVS examination revealed a summation gallop and grade 2/6 ESM at left parasternal border.  Abdominal exam was normal.  Rectal exam showed mild BPH and a symmetrical peripheral neuropathy was evident.  No pulses detectable below popliteal region.
Laboratory Studies Hemoglobin 14.39% WBC 17,900/mm 3 L. shift 7% bands Platelets 390,000/mm 3 BUN 79 mg% Creatinine 3.1% ABG/electrolytes Moderate ketoacidosis Glucose 480 mg% Urine WBC – TNTC Numerous bacteria Gram stain – GNR Glucose ++1 Protein ++1 Yeast +
Laboratory Studies Blood cultures pending Urine cultures pending Abdominal ultrasound:  moderate right hydronephrosis
A presumptive diagnosis of urosepsis with ketoacidosis and dehydration was made and in the E.R. patient was given Cefepime, rehydration and insulin and transferred to MICU.
Over the Next 48 Hours Rehydrated and electrolytes and metabolic  status corrected BP 150/75, Pulse 115/m Fails to defervesce – 102.8°F Blood culture positive for a yeast Urine cultures: 10 5 /ml  E. coli 10 5 /ml  Candida albicans 10 5 /ml   Candida glabrata
Issues Initially treated for bacterial pyelonephritis only –  with marginal benefit Candidemia needs to be treated. Which antifungal? Consideration in selecting antifungal Renal insufficiency Urine concentrations of antifungal Candida species identification Pathogenesis
Given fluconazole 100 mg IV/daily BUT Remained febrile, tachycardiac Blood cultures pending I.D. consult obtained
MRI of abdomen obtained Right hydronephrosis, mild hydroureter Mass in right dilated pelvis Urology – placed right nephrostomy tube Dye study via tube revealed a mass  suggestive of fungus ball and papillary  necrosis
Selecting an Antifungal Choices   Amphotericin B desoxycholate (conventional) Lipid formulation  - Ambisome ® - Abelcet ® IV azole - Fluconazole  - Itraconazole - Voriconazole - Posaconazole IV echinocandin - Caspofungin - Anidulafungin - Micafungin Combination - AmB + fluconazole - AmB + flucytosine Sequential
A Look At The Antifungal Choices   Amphotericin B desoxycholate Mainstay for > 30 years Broad spectrum, fungicidal Predictable/?inevitable toxicity Many experts no longer use AmB!!!
Still Role for Conventional AmB??   Nearly normal renal function Not receiving other nephrotoxic agents Short course anticipated Able to tolerate a few chills Neonate (amazing toleration) Experienced physician who understands azotemia  is temporary and side effects manageable    Maybe Not
Fluconazole -  How Good?
Fluconazole   Advantages Safe, excellent penetration Effective and broad spectrum C. albicans  resistance continues to be rare Inexpensive Can switch to oral with excellent absorption
Concerns About Fluconazole   Candida krusei  - Yes, but… Other  Candida  non- albicans  species No problem except   C. glabrata Persistent candidemia 10-15% (usually with in vitro sensitive strains)
Concerns About Fluconazole - C. glabrata MIC’s: 57% Susceptible ( <  8 µg/ml) 32% S-DD (16-32  µg/ml) 11% Resistant ( >  64 µg/ml) Can we overcome resistance with    dose 800 mg/d? No supporting data! Have we seen clinical resistance i.e. failure with  C. glabrata ??  Not really? In Rex study 9/11 responded Anecdotal failure  Yes Worth the risk??  Stable patient – Yes (BSI ~ 15-30%) Seriously ill – No!!!
Fluconazole + AmB Combination 1 Not antagonistic Faster clearance of blood cultures Lowest rates of persistent candidemia More toxic Enthusiasm for combination  ↓ with  arrival of newer antifungals 1 Rex J et al, CID, 2003
What About IV Itraconazole? Late in coming – why?  No IV Now IV itraconazole in cyclodextrin  200 mg q 12h x 2 d then 200 mg/d Oral solution equivalent to oral fluconazole Slightly broader spectrum but more drug  interactions Little data but probably equivalent in efficacy  for  Candida
Voriconazole? Drug of first choice for primary therapy of IA Extremely useful for emerging moulds  fusarium, scedosporium spp. also crypto   But not Zygomycetes In fact, 3 major reports of Zygomycosis in  HSCT while on vori What about  Candida  spp.?
Voriconazole? In vitro 10-100x more active than fluconazole Active against  C. krusei Active against  C. glabrata  but MIC’s are  higher!! Clinically As effective as fluconazole in OPC/EC  (Ally et al 2001) Effective against fluconazole-resistant  mucositis ~70%
Voriconazole for Candidemia RCT versus AmB followed by Fluconazole 422 non-neutropenies, in non-inferiority study Response at 12 weeks 40.7% versus 40.7% - Equivalent! Median clearance blood Cx – 2 days More renal toxicities in AmB/fluc Potential as broad spectrum initial choice  + later orally
Any Problems With Voriconazole > expensive than fluconazole ½ life 6 hr – dose b.i.d. IV not in presence of renal failure Does not get into urine > side-effects than fluconazole e.g.  visual/photopsia > drug interactions e.g. rifampin
Posaconazole Not yet available commercially Oral and eventually IV May have role in mucormycosis for prolonged oral therapy after response to AmB (or 1° or combination therapy) Emerging moulds
What about the echinocandins??
Echinocandins Fungal Cell Wall 1 Non-competitive Inhibition by : Lipopeptide Class of Antifungals (Enchinocandins, Pnuemocandins, Papulacandins)  2 GTP UDP glucose Catalytic subunit Regulatory Subunit  (GTPase) Continuous fibrils of Glucan Fibrous (  1,3) Glucan Plasma Membrane  (phospholipid bilayer) Surface-Layer Mannoprotein  1-6 Tail  1-6 Branched Glucan Entrapped Mannoprotein Chitin Plasma Membrane Glycosyl Phosphatidylinositol  “(GPI) Anchor”  (to mannoproteins)  1,3) Glucan Sythase Enzyme Complex 1 Adapted from: Kurtz, MB.  ASM News . Jan 1998;64(1):31-9. 2 Chiou CC et al.  Oncologist , 2000;5:120-35.  Ergosterol Chitin Synthase Candida, Aspergillus
Inhibits b1-3 GS, active in growing  Candida ,  Aspergillus   hyphal tips and branches Not active against organisms that don’t have b1-3 glucan  Poor oral bioavailability Long half-life (adult 9-11 hours)  Single daily dosing Minimal renal clearance No dose adjustment for renal failure Few toxicities Hepatotoxicities reported with CyA Caspofungin
Caspofungin Candidiasis Randomized, double-blind, multi-center, powered to  show non-inferiority Stratified for disease severity and neutropenia, then  randomly assigned to receive either IV caspofungin OR IV amphotericin B minimum of 10 days of IV therapy required; antifungal  therapy continued for 14 days after last positive  Candida  culture The primary efficacy endpoint  overall (clinical and microbiological) response at the  end of therapy Response unfavorable if study drug withdrawn before  improvement Mora-Duarte J et al.  N Engl J Med . 2002;347(25):2020-9.
Caspofungin versus Amphotericin B for  Invasive Candidiasis 0 20 40 60 80 100 Successful outcomes (%) 73% 62% 81% 65% Analysis of all patients (non-stratified) Successful outcome = symptom resolution and microbiological clearance Modified ITT Evaluable patients Mora-Duarte J et al.  N Engl J Med . 2002;347(25):2020-9. Caspofungin Amphotericin B
Any Problems With Caspofungin?? Excellent safety record Urinary tract infections?    MIC’s with  C. parapsilosis -    representation among persistent candidemia - Relevant? Resistance -  Large epidemiologic surveys – not a problem However - Resistance seen in few clinical isolates of  C. albicans  and  C. parapsilosis - Resistant in murine model
Treatment of Urosepsis Due to  Candida  spp. Select systemic antifungal for  Options: Polyene – AVOID! Caspofungin Voriconazole Fluconazole Flucytosine Nephrostomy tube Remove fungus ball/debris Local infusion of AmB, azole, caspofungin Remove obstruction

Update On Antifungals,Grand Round

  • 1.
    Update on NewAntifungals Grand Rounds Jack D. Sobel, M.D. Professor of Medicine Wayne State University School of Medicine Detroit, MI
  • 2.
    A 74-year-old maleis admitted with a one day history of fever, chills and rigors. He also reports nausea, vomiting but denies any urinary or respiratory symptoms. He is a Type I, severe diabetic on a moderately high dose of insulin, whose control has been poor. Past medical history is positive for two episodes of myocardial infarction, coronary angioplasty ~2002, moderate intermittent claudication and a mixed sensory-motor peripheral neuropathy. Hypertension for approximately 20 years.
  • 3.
    In the E.M.Department, he was found to be moderately dehydrated, temperature 103.2°F, pulse 128/m, BP 110/60, but was lucid and fully orientated. JVP not elevated, lungs clear to auscultation and CVS examination revealed a summation gallop and grade 2/6 ESM at left parasternal border. Abdominal exam was normal. Rectal exam showed mild BPH and a symmetrical peripheral neuropathy was evident. No pulses detectable below popliteal region.
  • 4.
    Laboratory Studies Hemoglobin14.39% WBC 17,900/mm 3 L. shift 7% bands Platelets 390,000/mm 3 BUN 79 mg% Creatinine 3.1% ABG/electrolytes Moderate ketoacidosis Glucose 480 mg% Urine WBC – TNTC Numerous bacteria Gram stain – GNR Glucose ++1 Protein ++1 Yeast +
  • 5.
    Laboratory Studies Bloodcultures pending Urine cultures pending Abdominal ultrasound: moderate right hydronephrosis
  • 6.
    A presumptive diagnosisof urosepsis with ketoacidosis and dehydration was made and in the E.R. patient was given Cefepime, rehydration and insulin and transferred to MICU.
  • 7.
    Over the Next48 Hours Rehydrated and electrolytes and metabolic status corrected BP 150/75, Pulse 115/m Fails to defervesce – 102.8°F Blood culture positive for a yeast Urine cultures: 10 5 /ml E. coli 10 5 /ml Candida albicans 10 5 /ml Candida glabrata
  • 8.
    Issues Initially treatedfor bacterial pyelonephritis only – with marginal benefit Candidemia needs to be treated. Which antifungal? Consideration in selecting antifungal Renal insufficiency Urine concentrations of antifungal Candida species identification Pathogenesis
  • 9.
    Given fluconazole 100mg IV/daily BUT Remained febrile, tachycardiac Blood cultures pending I.D. consult obtained
  • 10.
    MRI of abdomenobtained Right hydronephrosis, mild hydroureter Mass in right dilated pelvis Urology – placed right nephrostomy tube Dye study via tube revealed a mass suggestive of fungus ball and papillary necrosis
  • 11.
    Selecting an AntifungalChoices Amphotericin B desoxycholate (conventional) Lipid formulation - Ambisome ® - Abelcet ® IV azole - Fluconazole - Itraconazole - Voriconazole - Posaconazole IV echinocandin - Caspofungin - Anidulafungin - Micafungin Combination - AmB + fluconazole - AmB + flucytosine Sequential
  • 12.
    A Look AtThe Antifungal Choices Amphotericin B desoxycholate Mainstay for > 30 years Broad spectrum, fungicidal Predictable/?inevitable toxicity Many experts no longer use AmB!!!
  • 13.
    Still Role forConventional AmB?? Nearly normal renal function Not receiving other nephrotoxic agents Short course anticipated Able to tolerate a few chills Neonate (amazing toleration) Experienced physician who understands azotemia is temporary and side effects manageable  Maybe Not
  • 14.
    Fluconazole - How Good?
  • 15.
    Fluconazole Advantages Safe, excellent penetration Effective and broad spectrum C. albicans resistance continues to be rare Inexpensive Can switch to oral with excellent absorption
  • 16.
    Concerns About Fluconazole Candida krusei - Yes, but… Other Candida non- albicans species No problem except C. glabrata Persistent candidemia 10-15% (usually with in vitro sensitive strains)
  • 17.
    Concerns About Fluconazole- C. glabrata MIC’s: 57% Susceptible ( < 8 µg/ml) 32% S-DD (16-32 µg/ml) 11% Resistant ( > 64 µg/ml) Can we overcome resistance with  dose 800 mg/d? No supporting data! Have we seen clinical resistance i.e. failure with C. glabrata ?? Not really? In Rex study 9/11 responded Anecdotal failure Yes Worth the risk?? Stable patient – Yes (BSI ~ 15-30%) Seriously ill – No!!!
  • 18.
    Fluconazole + AmBCombination 1 Not antagonistic Faster clearance of blood cultures Lowest rates of persistent candidemia More toxic Enthusiasm for combination ↓ with arrival of newer antifungals 1 Rex J et al, CID, 2003
  • 19.
    What About IVItraconazole? Late in coming – why? No IV Now IV itraconazole in cyclodextrin 200 mg q 12h x 2 d then 200 mg/d Oral solution equivalent to oral fluconazole Slightly broader spectrum but more drug interactions Little data but probably equivalent in efficacy for Candida
  • 20.
    Voriconazole? Drug offirst choice for primary therapy of IA Extremely useful for emerging moulds fusarium, scedosporium spp. also crypto But not Zygomycetes In fact, 3 major reports of Zygomycosis in HSCT while on vori What about Candida spp.?
  • 21.
    Voriconazole? In vitro10-100x more active than fluconazole Active against C. krusei Active against C. glabrata but MIC’s are higher!! Clinically As effective as fluconazole in OPC/EC (Ally et al 2001) Effective against fluconazole-resistant mucositis ~70%
  • 22.
    Voriconazole for CandidemiaRCT versus AmB followed by Fluconazole 422 non-neutropenies, in non-inferiority study Response at 12 weeks 40.7% versus 40.7% - Equivalent! Median clearance blood Cx – 2 days More renal toxicities in AmB/fluc Potential as broad spectrum initial choice + later orally
  • 23.
    Any Problems WithVoriconazole > expensive than fluconazole ½ life 6 hr – dose b.i.d. IV not in presence of renal failure Does not get into urine > side-effects than fluconazole e.g. visual/photopsia > drug interactions e.g. rifampin
  • 24.
    Posaconazole Not yetavailable commercially Oral and eventually IV May have role in mucormycosis for prolonged oral therapy after response to AmB (or 1° or combination therapy) Emerging moulds
  • 25.
    What about theechinocandins??
  • 26.
    Echinocandins Fungal CellWall 1 Non-competitive Inhibition by : Lipopeptide Class of Antifungals (Enchinocandins, Pnuemocandins, Papulacandins) 2 GTP UDP glucose Catalytic subunit Regulatory Subunit (GTPase) Continuous fibrils of Glucan Fibrous (  1,3) Glucan Plasma Membrane (phospholipid bilayer) Surface-Layer Mannoprotein  1-6 Tail  1-6 Branched Glucan Entrapped Mannoprotein Chitin Plasma Membrane Glycosyl Phosphatidylinositol “(GPI) Anchor” (to mannoproteins)  1,3) Glucan Sythase Enzyme Complex 1 Adapted from: Kurtz, MB. ASM News . Jan 1998;64(1):31-9. 2 Chiou CC et al. Oncologist , 2000;5:120-35. Ergosterol Chitin Synthase Candida, Aspergillus
  • 27.
    Inhibits b1-3 GS,active in growing Candida , Aspergillus hyphal tips and branches Not active against organisms that don’t have b1-3 glucan Poor oral bioavailability Long half-life (adult 9-11 hours) Single daily dosing Minimal renal clearance No dose adjustment for renal failure Few toxicities Hepatotoxicities reported with CyA Caspofungin
  • 28.
    Caspofungin Candidiasis Randomized,double-blind, multi-center, powered to show non-inferiority Stratified for disease severity and neutropenia, then randomly assigned to receive either IV caspofungin OR IV amphotericin B minimum of 10 days of IV therapy required; antifungal therapy continued for 14 days after last positive Candida culture The primary efficacy endpoint overall (clinical and microbiological) response at the end of therapy Response unfavorable if study drug withdrawn before improvement Mora-Duarte J et al. N Engl J Med . 2002;347(25):2020-9.
  • 29.
    Caspofungin versus AmphotericinB for Invasive Candidiasis 0 20 40 60 80 100 Successful outcomes (%) 73% 62% 81% 65% Analysis of all patients (non-stratified) Successful outcome = symptom resolution and microbiological clearance Modified ITT Evaluable patients Mora-Duarte J et al. N Engl J Med . 2002;347(25):2020-9. Caspofungin Amphotericin B
  • 30.
    Any Problems WithCaspofungin?? Excellent safety record Urinary tract infections?  MIC’s with C. parapsilosis -  representation among persistent candidemia - Relevant? Resistance - Large epidemiologic surveys – not a problem However - Resistance seen in few clinical isolates of C. albicans and C. parapsilosis - Resistant in murine model
  • 31.
    Treatment of UrosepsisDue to Candida spp. Select systemic antifungal for Options: Polyene – AVOID! Caspofungin Voriconazole Fluconazole Flucytosine Nephrostomy tube Remove fungus ball/debris Local infusion of AmB, azole, caspofungin Remove obstruction