Treatment of Invasive Aspergillosis: Polyenes, Azoles, Echinocandins? Thomas F. Patterson, MD Professor of Medicine Director, San Antonio Center for Medical Mycology The University of Texas Health Science Center at San Antonio
Mar 27, 2015
Treatment of Invasive Aspergillosis:
Polyenes, Azoles, Echinocandins?
Thomas F. Patterson, MDProfessor of Medicine
Director, San Antonio Center for Medical Mycology
The University of Texas Health Science Centerat San Antonio
New (and newer) antifungals for invasive aspergillosis
Azoles
• itraconazole (i.v.)
• voriconazole
• posaconazole
• ravuconazole
• BAL 8557/4815
Echinocandins
• caspofungin
• micafungin
• anidulafungin
• aminocandin
Polyenes
• ABLC, ABCD,
AmBisome
• liposomal nystatin
• inhaled amphotericin B
Note: ABLC=amphotericin B lipid complex; ABCD= amphotericin B colloidal dispersion
Note: Blue text, earlier stage development
Treatment of Invasive Aspergillosis: Polyenes, Azoles,
or Echinocandins?
• Key questions: Why have outcomes been so bad? What is the impact of early diagnosis? What are options for therapy?
- Disseminated infection?- Severely immunocompromised?
Can we do better?- Role of combination therapy?- How can management strategies improve
outcome?
Invasive Aspergillosis in Transplant Recipients
Type of Transplant Incidence Range, % (Mean)
Mortality (%)
Lung 3-14% (6%) 68%
Liver 1-8 (2) 87
Heart 1-15 (5) 78
Kidney 0-4 (1) 77
Small bowel 0-10 (2) 66
Allogeneic stem cell 5-26 (10) 78-92
Autologous stem cell 2-6 (5) 78-92
Nonmyeloblative stem cell 8-23 (11) 63-67
Singh N & Paterson DL, Clin Microbiol Rev 2005;18:44-69.
Acute Renal Failure and Amphotericin B: Hidden Costs of Toxicity
• Mortality and costs of acute renal failure 707 adult patients receiving amphotericin B
• Clinical impact Acute renal failure: 212 (30%) Higher mortality with acute renal failure: 54% vs 16%
• Economic impact Mean increase length of hospital stay: 8.2 days Mean increase hospital cost: $29,823
Bates DW et al, Clin Infect Dis, 2001;32:686-93
A. flavus12%
A. niger10%
A. sydowii2%
A. ustus2%
A. versicolor2%
A. fumigatus57%
A. terreus12%
Aspergillus spp. Isolates Submitted to San Antonio Fungus Testing Laboratory918 Isolates; Jan. 2001-July 2004
AmB=Amphotericin B; MFC=Minimum Fungicidal Concentration; MIC=Minimum Inhibitory ConcentrationSutton D et al, Advances Against Aspergillus 2004 (Abstract 16)
A. nidulans 3%
AmB MFC >16 A. fumigatus 24%
AmB MIC>2 A. terreus 90% A. flavus 51% A. ustus
50%
Lipid Preparations of Amphotericin B: Rationale for Use
• Polyene: broad spectrum of activity• Lipid formulations of amphotericin B
Reduced toxicities of intravenous amphotericin B deoxycholate
Improved therapeutic index: ≥5 mg/kg/d well tolerated- Salvage therapy (limited efficacy 40% responded)- Empiric therapy (reduced efficacy vs moulds at lower doses)
• Limited data for primary therapy; most studies in empirical use
• Target use for patients with documented need (eg Zygomycosis, intolerance or progressive infection) Cost remains significant obstacle to use!
Efficacy of Liposomal AmB (L-AmB) in Invasive Mycoses: AmBiLoad Trial
Proven/Probable Invasive Fungal Infection
50% 46%
0
20
40
60
80
100
L-AmB 3 mg/kg/d(n=107)
L-AmB 10 mg/kg/d(n=94)
Resp
onse
at E
OT (C
R+PR
) (%
)
• 14 day loading dose of L-AmB 3 or 10 mg/kg/d followed by L-AmB 3 mg/kg/d
Cornely O et al. ASH 2005 (Abstract 3222)
Note: L-AmB=liposomal amphotericin B; CR+PR=complete & partial responses; EOT=End of Therapy; IPA=invasive pulmonary aspergillosis;Allo-SCT=allogeneic stem cell transplant
L-AmB 3 L-AmB 10
IPA 96% 97%
CT Halo 58 60
Allo-SCT 16 19
Neutropenia 71 76
Survival 72 59
Toxicity 20 32
Continuous Infusion Amphotericin B
• 24 hour continuous infusion Dose escalated to 2 mg/kg/d when tolerated Median duration of therapy 16 d (range 7-72d) Infusion-related reactions: 18% >2-fold increase in creatinine: 16% Dose-limited toxicity: 1/33
• Concerns Limited efficacy data in documented infection Poor efficacy of amphotericin B in invasive aspergillosis Animal models: Peak serum level/MIC best predictor of
outcome
Imhof A, et al, Clin Infect Dis 2003:36:943-51;Andes D, et al, Antimicrob Agents Chemother 2001;45:922-6
Bowman et al. Antimicrobial Agents Chemother 2002;46:3001-3012
In Vitro Effects of Echinocandins on Growth of Aspergillus
In vitro activity: • Not classically
fungicidal or fungistatic
• Activity against other Aspergillus spp. (A terreus)
• Animal models prolonged survival
LivingCells
DeadCells
ControlCells
AmBAmB CaspoCaspo ItraItraAmphotericin B
0.15 g/mLCaspofungin0.30 g/mL
Itraconazole2.6 g/mL
Echinocandins in Invasive Aspergillosis
• Study conducted in patients with well-documented, refractory infection
• Efficacy Progressive infection Multiple prior antifungals• Excellent tolerability• Clinical utility for moulds Combination therapy (not
primary therapy) Activity: Aspergillus (not
Zygomycetes or other moulds)
Maertens J et al. Clin Infect Dis 2004;39:1563-71
Proven/Probable Invasive Aspergillosis
41
17
0
20
40
60
80
100
Caspofungin(n=56)
HistoricalControls (n=206)
Com
plet
e/Pa
rtial
Res
pons
es(%
)
%
%
Posaconazole Salvage Therapy for Invasive Aspergillosis
• Open, salvage therapy; historical controls refractory or intolerant of standard therapy
• Posaconazole: Oral solution (200mg qid X2 wk/400mg bid)
• Adverse events: 4-10% (Headache, abdominal pain, nausea, liver
enzyme elevations)
Raad I, et al. ICAAC 2004 (Abstract M-669)
Aspergillus species Posaconazole (n) Historical Controls (n)
All Aspergillus 42% (107) 26% (86)
A. fumigatus 41% (29) 35% (34)
A. flavus 53% (19) 19% (16)
A. terreus 29% (14) 18% (11)
Voriconazole in Invasive Aspergillosis: Global Comparative Study
• Satisfactory (Complete/Partial Responses) at week 12 Difference: 21.2%
• Improved survival with voriconazole
• Importance of early therapy • Limited role for rescue therapy• Lower success in high risk
patients Disseminated infection Allogeneic Bone Marrow
Transplantation- Voriconazole: 32.4%- Amphotericin B: 13.3%
Responses at week 12
31.6
52.8
0
20
40
60
80
100
Voriconazole ±OLAT (n=144)
Amphotericin B ±OLAT (n=133)
Com
plet
e/Par
tial R
espo
nses
(%)
%
%
Herbrecht R et al NEJM 2002;347:408-15;Patterson TF et al, Clin Infect Dis 2005;41:1448-52
Note: OLAT=other licensed antifungal therapy
The Strategy of Following Voriconazole (Vori) or Amphotericin B (AmB) with Other Licensed
Antifungal Therapy (OLAT)
Pts switched to lipid formulations of AmB following initial AmB had success in 14/47 (30%)No antagonism demonstrated with AmB following Voriconazole
Herbrecht R et al. NEJM 2002;347:408-15;Patterson TF et al. Clin Infect Dis 2005 2005;41:1448-52
Category/Reason for switch Success at wk 12 (%)
Vori (n=144) AmB (n=133)
Received OLAT 25/52 (48%) 41/107 (38%)
Intolerance (adverse event, lab abnormality) 8/19 (42) 27/74 (36)
Insufficient clinical response 5/16 (31) 4/19 (21)
Completed therapy and received OLAT 11/14 (79) 6/10 (60)
Other 1/3 4/4
Overall success 76/144 (53) 42/133 (32)
Voriconazole: Important Considerations
• Watch for drug interactions
• Significant adverse events: hepatic, visual, rash
• IV formulation: accumulation of cyclodextrin in renal insufficiency
• Potential for azole cross-resistance
• No activity versus Zygomycetes
Patients with Satisfactory Treatment ResponseCategorized by Baseline CT Findings
60%
53%
45%
67%
37%32%
19%
44%
0%
10%
20%
30%
40%
50%
60%
70%
ALL Patients Definite Probable Probable(Radiology alone)
Sati
sfa
cto
ry (
Co
mp
lete
/Part
ial)
Resp
on
ses
Voriconazole
Amphotericin B
2126
2323
Herbrecht R et al NEJM 2002;347:408-15;Patterson TF et al, Clin Infect Dis 2005;41:1448-52;Greene R et al. ECCMID 2003
Non-Culture Based Diagnosis of Invasive Aspergillosis
• Galactomannan Sandwich ELISA (Platelia)
• PCR TaqMan, LightCycler PCR 18s ribosomal DNA Multi-copy or single target genes
• -D-glucan Amebocyte Limulus lysate Chromogenic (Fungitell) Kinetic (Wako)
Screening for Invasive Aspergillosis using Aspergillus Platelia EIA
• Maertens et al (2001) Sensitivity: 89%; Specificity: 98%
- Serial testing needed for optimal results
• Herbrecht et al (2002); Marr et al (2004) Limited sensitivity (43-70%); Better specificity (70-93%) Lower cut-off on empirical antifungals or prophylaxis
- Original criteria: Pos (Index 1.0-1.5) on 2 consecutive samples- US: Pos (0.5) on repeat testing (same sample)- EU: Pos (0.5-0.7); dynamic endpoint (Maertens, 2005)
• False-positive results (Verweij, 1998) Weakly positive samples ■ Cross-reactivity Laboratory contamination ■ Dietary Piperazillin/Tazobactam (Viscoli, 2003; Sulahian, 2003)
Detection of GM in the Diagnosis & Management of Invasive Aspergillosis
• Utility of GM at baseline Patients with EORTC/MSG confirmed IA 60/144 (41.7%) positive (O.D. ≥ 0.5) Limited number of samples
• Utility of GM in serial samples Poor correlation between baseline level & response Trend to poorer clinical response with higher antigen titers after
5 days
Herbrecht R et al, Advances Against Aspergillosis, 2004
Utility of -Glucan Detection in Invasive Fungal Infection
• 30 candidemic pts/30 controls Cut-off >60 pg/ml
• 283 pts AML/MDS (twice weekly samples) Sensitivity: 20/20 IFI pts at
least one positive Specificity: 90% Organisms detected:
Candida, Aspergillus, Trichosporon, Fusarium
• 163 pt IFI/170 controls (single samples) Sensitivity: 70% Specificity: 87%
Obadasi Z et al. Clin Infect Dis 2004;39:199-205; Ostrosky-Zeichner L et al. Clin Infect Dis 2005;41:654-9
Design Sens (%) Spec (%) Ref
Pan-fungal 100 98 JCM 1997;35:1353-60
Pan-fungal 75 96 BJH 2001;113:180-4
Asp. sp. 100 65 JID 2000;181:1713-9
Asp. sp. 91.7 81.3 CID 2001;33:428-35
Asp. sp. 79 92 CID 2001;33:1504-12
Asp. sp. 64 64 BJH 2004;125:196-202
Asp. sp. 92 95 CID 2006;42:479-82
PCR for Invasive Aspergillosis
•Variable sensitivity / specificity•Limited per test positivity•Technical false positives/negatives•Lack of standardized targets/reagents•Not externally validated
Donnelly JP. Clin Infect Dis 2006;42:487-9
PCR not (yet) accepted for mycological criteria
Diagnostic Strategies in Invasive Aspergillosis
• Consideration of risk• Role of mycological diagnosis
Predictive value of positive cultures in high risk patients
• Utility of radiological procedures• Non-culture based diagnostics
Impact of antifungal therapies Value of serial samples Significance of false negative/false positive results Role of testing in other body fluids, including CSF & BAL
• Role of surrogate markers in decision making & impact on mortality
Combination Therapy: Candins• In vitro
Most interactions show synergy / additive effects (Perea, 2002)
Poor correlation between in vitro results and in vitro efficacy (Johnson, 2004)
• Experimental infections Candin plus polyene (Kohno, 2000;
Nakajima, 2000) Candin plus azole (Kirkpatrick, 2002;
Petraitiene, 2002)- Improved sterilization of tissues- Reduced tissue burden
• Anecdotal clinical series Candin+polyene (Aliff, 2003; Kontoyiannis,
2003; Ratanatharathorn, 2002) Candid plus azole (Marr, 2004)
Efficacy of Empirical Antifungal Therapy in Neutropenic Patients
Walsh TJ et al, New Engl J Med 2002;346:225-34
4
13
4
8
0 5 10 15 20 25
Vori(n=415)
L-AmB(n=422)
Fungal Infections (#)
Aspergillus Other
21/422 (5%)
8/415 (1.9%)
• Voriconazole vs liposomal amphotericin B
Composite success: 26% vs 31%
High risk patients: 18% allogeneic BMT
Similar survival, fever resolution, toxicity or lack of efficacy
Fewer breakthrough infections
• Efficacy in high risk: Breakthrough infections:
2/143 (2%) vs 13/143 (9%)
Caspofungin vs Liposomal Amphotericin B for Empirical Antifungal Therapy in Patients
with Fever & Neutropenia
Walsh TJ et al, New Eng J Med, 2004;351:1391-1402*Patients may have had more than one organism
Caspofungin
(n=556)
Liposomal Amphotericin B
(n=539)
Composite Success 33.9% 33.7%
Success Baseline Infections 14/27 (52%) 7/27 (26%)
Breakthrough Infections 29 (5.2%) 24 (4.5%)
Etiological Agents*
Aspergillus 10 9
Candida 16 15
Fusarium 1 0
Zygomycetes 2 0
Other 1 1
Invasive Aspergillosis: Polyenes, Azoles or
Echinocandins?• Importance of early detection
Role of radiological diagnosis Non-culture based diagnostics
- Importance of serial samples- Impact of prior therapy
Poorer outcomes with extensive disease• Poor efficacy of amphotericin B in high risk patients
Improved responses with early effective therapy Utility of early targeted therapy
• Role of new agents in invasive aspergillosis Efficacy of voriconazole as primary therapy Options for salvage therapy: posaconazole,
echinocandins, lipid amphotericin formulations• Clinical trials needed combination therapy