Contains Nonbinding Recommendations 
Draft Guidance on Qualification of Biomarker  Galactomannan in studies of treatments of invasive 
Aspergillosis  
 
        
 
This draft guidance, once finalized, will represent the Food and Drug Administrations (FDAs) current 
thinking on this topic.  It does not create or confer any rights for or on any person and does not operate to 
bind FDA or the public.  You can use an alternative approach if the approach satisfies the requirements of 
the applicable statutes and regulations. If you want to discuss an alternative approach, contact the Center 
for Drug Evaluation and Research, Biomarker Qualification Program (email:  CDER-
BiomarkerQualificationProgram@fda.hhs.gov).   
 
 
 
1  Drug Development Tool (DDT) Type:  Biomarker   
2   
3  DDT Tracking Number: [DDTBMQ-000001] 
4   
5  Referenced Biomarker(s):  Galactomannan in serum and bronchoalveolar lavage (BAL) 
6  fluid.  
7   
8  Galactomannan is a heat-stable and water soluble cell wall polysaccharide that is released by 
9  Aspergillus species during fungal growth. 
10   
11  This guidance describes a qualified context of use for galactomannan detection in serum 
12  and/or BAL fluid. The experimental conditions and constraints (below) describe conditions 
13  for galactomannan use in the qualified context.  Galactomannan use in drug development 
14  not conforming to the complete context of use will be considered on a case-by-case basis in 
15  regulatory submissions (e.g., investigational new drug application (IND), biologics licensing 
16  application (BLA), or new drug application (NDA)); in such cases, additional information 
17  relevant to the expanded use may be requested by the Center for Drug Evaluation and 
18  Research product review team.  
19   
20  This guidance applies to research use only in investigational studies of treatments for invasive 
21  aspergillosis (IA), and does not change any regulatory status, decisions, or labeling of any test 
22  used in medical care of patients. 
23   
24  Section I: Context of Use (COU) 
25       
26  A.  Use Statement:  Galactomannan in serum and/or BAL fluid is qualified as a sole 
27  microbiological criterion to classify patients as having probable IA as defined by the 
28  European Organization for Research and Treatment of Cancer/Invasive Fungal Infections 
29  Cooperative Group and Infectious Diseases Mycoses Study Group (EORTC/MSG) in 
  1  Contains Nonbinding Recommendations 
Draft Guidance on Qualification of Biomarker  Galactomannan in studies of treatments of invasive 
Aspergillosis  
 
30  2008,1 for enrollment in, and analysis of, clinical trials conducted to evaluate the efficacy 
31  and safety of drugs for the treatment of IA. 
32      
33  B.  Conditions for Qualified Use: 
34    
35  1.  Assay: A validated assay (see section III), such as the Bio-Rad Platelia 
36  Aspergillus enzyme immunoassay (EIA), should be used for galactomannan 
37  detection as a biomarker.  
38   
39  2.  Patient populations: 
40   
41  a.  The use of galactomannan, as the sole microbiological criterion for diagnosis 
42  of IA, is restricted to patients with hematologic malignancies or recipients of 
43  hematopoietic stem cell transplant (HSCT) who also have clinical and 
44  radiologic features consistent with invasive fungal infection as defined by 
45  EORTC/MSG in 2008 (see footnote 1). 
46   
47  b.  Subjects enrolled in a treatment trial who satisfy the clinical and radiologic 
48  criteria and the following microbiological criteria can be classified as 
49  EORTC/MSG category probable IA when using the Bio-Rad Platelia 
50  Aspergillus EIA: 
51   
52  Serum: A positive result should be based on a cut-off galactomannan index  
53  0.5 based on testing of two separate serum samples or a single sample with a 
54  value of  1.0; and/or 
55      
56  BAL fluid: A positive result should be based on a cut-off galactomannan 
57  index  1.0 based on testing of two aliquots of a single BAL fluid sample.  
58   
59  The quantitative value of the galactomannan index should be documented in 
60  the case report forms and included in the electronic datasets.  
61   
62  c.  For other assays, appropriate cut-off parameters (for example, values or 
63  indices) should be determined and discussed with FDA prior to initiating the 
64  clinical trial.  The quantitative value of the galactomannan measures should 
65  be documented in the case report forms and included in the electronic 
66  datasets.  
67   
68  3.  Limitations of use of the galactomannan assay: 
                                                           
1 De Pauw B, Walsh TJ, Donnelly JP, et al. Revised Definitions of Invasive Fungal Disease from European 
Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National 
Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group. Clin Infect 
Dis (2008) 46: 1813-1821. 
  2  Contains Nonbinding Recommendations 
Draft Guidance on Qualification of Biomarker  Galactomannan in studies of treatments of invasive 
Aspergillosis  
 
69   
70  a.  Use of fluids that contain sodium gluconate should be avoided when 
71  performing a BAL. The presence of electrolyte solutions containing sodium 
72  gluconate, such as PlasmaLyte, may yield false positive results in the 
73  galactomannan assay.   
74   
75  b.  Piperacillin/tazobactam may yield false positive assay results. Patients who 
76  have recently received or are receiving this antibacterial drug can be enrolled 
77  in clinical trials after samples for galactomannan testing are obtained; 
78  however, the timing of administration of the antibacterial drugs in relation to 
79  sample collection and name of the manufacturer should be recorded so that a 
80  sensitivity analysis can be performed.   
81   
82    FDA is aware of studies in progress to evaluate whether newer preparations of 
83  piperacillin/tazobactam exhibit cross-reactivity.  If these studies do not 
84  eliminate concerns of cross-reactivity with piperacillin/tazobactam, then 
85  patients enrolled based upon the galactomannan findings as the sole 
86  microbiologic criterion after receiving piperacillin/tazobactam should not be 
87  considered evaluable in the primary efficacy analyses. Sponsors are advised to 
88  discuss this issue with FDA. 
89   
90  c.  The antibacterial drug amoxicillin/clavulanate has been reported to cause false 
91  positive results of the galactomannan assay.  Patients who recently received or 
92  who are receiving this antibacterial drug should not be enrolled into a study 
93  based upon positive galactomannan assay results as the sole microbiologic 
94  criterion.  
95   
96  d.  Infection with certain other fungal pathogens, such as Penicillium, 
97  Paecilomyces, Geotrichum, and Histoplasma, may lead to a false positive 
98  galactomannan assay result for Aspergillus caused by cross-reactivity.  
99  Patients known to be infected with these pathogens should not be enrolled, 
100  and if enrolled, should be excluded from the analysis of efficacy.  
101   
102  4.  Considerations for sample acquisition and documentation:  
103   
104  a.  Investigators should comply with the standard practice of obtaining a fungal 
105  smear and culture on all clinically relevant samples. All positive and negative 
106  results should be documented on case report forms and included in the datasets.  
107  This is especially important for BAL samples so that the presence of Aspergillus 
108  species or rare fungal pathogens (such as Penicillium, Paecilomyces, 
109  Geotrichum, and Histoplasma) that may cross-react with the galactomannan 
110  assay are documented.   
111   
  3  Contains Nonbinding Recommendations 
Draft Guidance on Qualification of Biomarker  Galactomannan in studies of treatments of invasive 
Aspergillosis  
 
112  b.  A BAL fluid sample should be collected as soon as it is feasible because 
113  exposure to mold-active antifungal agents may affect the sensitivity of the 
114  galactomannan assay.  
115   
116  5.  Analysis of study results: 
117   
118  a.  When a noninferiority study design is used, the appropriate noninferiority 
119  margin should be determined in discussion with FDA at the time the study is 
120  proposed within an IND. 
121   
122  b.  The primary efficacy analysis should be performed on the modified intent-to-
123  treat population, which is defined as all proven and probable invasive IA.  
124  Proven and probable IA is defined as per the 2008 EORTC/MSG criteria. 
125  However, the use of a positive galactomannan assay (as described above) to 
126  classify a patient as probable IA is restricted to patients with hematological 
127  malignancies or HSCT recipients. 
128   
129  c.  A subset analysis should be done for patients that are diagnosed based on a 
130  positive culture and/or histopathology, excluding those whose 
131  microbiological diagnosis is based only on a galactomannan positive result. 
132   
133  d.  As stated above in section 2.a, patients with hematologic malignancy or 
134  recipients of HSCT who have a positive serum galactomannan assay without 
135  clinical or radiologic findings consistent with invasive fungal disease should 
136  not be enrolled, or if enrolled, should be excluded from analysis of efficacy. 
137   
138  Section II:   Supportive Information 
139   
140  The data to support qualification were obtained with use of the Bio-Rad Platelia Aspergillus EIA.  
141  The criteria for a positive galactomannan index described here for use in investigational studies 
142  of treatments for IA are different from the FDA-cleared Bio-Rad Platelia Aspergillus EIA device 
143  labeling. The recommendations of this guidance do not alter the labeling recommendations of the 
144  galactomannan assay for use in the medical care of patients, and cut-off values specified in the 
145  device labeling should continue to be used.  The use of different criteria for research is to 
146  increase the positive predictive value of the Bio-Rad Platelia Aspergillus EIA. 
147   
148  Section III:  Performance Characteristics of the Assay for the Qualification of 
149  Galactomannan 
150   
151  The data provided to support the current COU relied upon the Bio-Rad Platelia Aspergillus EIA 
152  for galactomannan detection in serum and BAL fluid that has been cleared by FDA for use in 
153  patient care.  For performance characteristics of the assay, see the 510(k) summaries on FDAs 
154  Web site: 
  4  Contains Nonbinding Recommendations 
Draft Guidance on Qualification of Biomarker  Galactomannan in studies of treatments of invasive 
Aspergillosis  
 
155    
156  http://www.accessdata.fda.gov/cdrh_docs/pdf2/K023857.pdf  (Serum) 
157  http://www.accessdata.fda.gov/cdrh_docs/pdf6/K060641.pdf (Serum) 
158  http://www.accessdata.fda.gov/cdrh_docs/reviews/K093678.pdf (BAL fluid) 
159   
160  A.  Other galactomannan assays: 
161   
162  Sponsors using non-FDA-cleared galactomannan assays for studies to be submitted 
163  within a drug development regulatory submission to FDA should determine the 
164  performance characteristics of the assay using clinical studies to assess performance 
165  against defined reference standards and should ensure that the assay is adequate for the 
166  COU.  For this performance assessment, analytical parameters such as precision, 
167  reproducibility, and cross-reaction with non-Aspergillus fungal species should be 
168  determined.  Sponsors should discuss their plans with FDA prior to conducting clinical 
169  studies.  
170   
171  For more details, please see supporting information:  Galactomannan Reviews 
172   
173  Instructions for Use in a Regulatory Submission:  Please reference DDT # and this guidance 
174  in your application.  
  5