Developing and 
Labeling In vitro 
Companion Diagnostic 
Devices for a Specific 
Group of Oncology 
Therapeutic Products 
 
Guidance for Industry 
 
 
 
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Oncology Center of Excellence 
Center for Devices and Radiological Health (CDRH) 
Center for Biologics Evaluation and Research (CBER) 
Center for Drug Evaluation and Research (CDER) 
 
 
April 2020 
Procedural 
 
    
Developing and Labeling In vitro 
Companion Diagnostic Devices for 
a Specific Group of Oncology 
Therapeutic Products 
Guidance for Industry 
 
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U.S. Department of Health and Human Services 
Food and Drug Administration 
Oncology Center of Excellence 
Center for Devices and Radiological Health (CDRH) 
Center for Biologics Evaluation and Research (CBER) 
Center for Drug Evaluation and Research (CDER) 
 
 April 2020 
Procedural 
  Contains Nonbinding Recommendations 
 
TABLE OF CONTENTS 
 
 
 
 
I.  INTRODUCTION............................................................................................................. 1 
II.  BACKGROUND ............................................................................................................... 2 
III.  DEVELOPMENT AND LABELING OF COMPANION DIAGNOSTICS IN 
ONCOLOGY ..................................................................................................................... 4 
IV.  CONSIDERATIONS REGARDING BROADER LABELING ................................... 5 
V.  PROCESS FOR BROADENING LABELING FOR APPROVED OR CLEARED 
COMPANION DIAGNOSTICS ...................................................................................... 9 
  Contains Nonbinding Recommendations 
 
Developing and Labeling In vitro Companion Diagnostic Devices for 
a Specific Group of Oncology Therapeutic Products 
Guidance for Industry 
 
 
This guidance represents the current thinking of the Food and Drug Administration (FDA or Agency) on 
this topic.  It does not establish any rights for any person and is not binding on FDA or the public.  You 
can use an alternative approach if it satisfies the requirements of the applicable statutes and regulations.  
To discuss an alternative approach, contact the FDA office responsible for this guidance as listed on the 
title page.   
 
 
 
 
I.  INTRODUCTION  
 
This guidance describes considerations for the development and labeling of in vitro companion 
diagnostic devices (referred to as companion diagnostics herein) to support the indicated uses 
of multiple drug or biological oncology products,1 when appropriate.  This guidance builds upon 
existing policy regarding the labeling of companion diagnostics.  In a prior guidance issued in 
2014, the Agency stated that if evidence is sufficient to conclude that the companion diagnostic 
is appropriate for use with a specific group of therapeutic products, the companion diagnostics 
intended use/indications for use should name the specific group of therapeutic products, rather 
than specific products.2  This guidance expands on the policy statement in the 2014 guidance by 
recommending that companion diagnostic developers consider a number of factors, including but 
not limited to those discussed in this guidance, when determining whether their test could be 
developed, or the labeling for approved companion diagnostics could be revised through a 
supplement, to support a broader labeling claim such as use with a specific group of oncology 
therapeutic products (rather than listing an individual therapeutic product(s)).    
 
For the purpose of this guidance, a specific group of oncology therapeutic products would be 
identified based on sufficient and consistent clinical experience with the therapeutics with the 
same approved indications,3 including molecular alteration(s), for which a companion diagnostic 
could potentially be labeled (as discussed in this document).  To illustrate FDAs current 
                                                 
1 For purposes of this guidance, drug and biological oncology products are referred to as therapeutic products or 
oncology therapeutic products. 
2 FDAs Guidance for Industry and FDA Staff: In Vitro Companion Diagnostic Devices, August 2014, page 11, 
available at:  https://www.fda.gov/regulatory-information/search-fda-guidance-documents/vitro-companion-
diagnostic-devices.  For the most recent version of a guidance, check the FDA guidance web page at 
https://www.fda.gov/RegulatoryInformation/Guidances/default.htm.  We note that the referenced guidance includes 
(emphasis added) In some cases, if evidence is sufficient to conclude that the IVD companion diagnostic device is 
appropriate for use with a class of therapeutic products, the intended use/indications for use should name the 
therapeutic class, rather than each specific product within the class.  However, in this document we use specific 
group of oncology therapeutic products rather than therapeutic class because depending on the indication, a 
specific group could be a therapeutic class, a subset of a class, or broader than a class.  
3 See section IV.1 for additional information. 
  1  Contains Nonbinding Recommendations 
 
thinking on this topic, the guidance discusses a specific example, companion diagnostics that 
identify patients with non-small cell lung cancer (NSCLC) whose tumors have the most common 
epidermal growth factor receptor (EGFR) mutations, exon 19 deletions or exon 21 (L858R) 
substitution mutations.   
 
In general, FDAs guidance documents do not establish legally enforceable responsibilities.  
Instead, guidances describe the Agencys current thinking on a topic and should be viewed only 
as recommendations, unless specific regulatory or statutory requirements are cited.  The use of 
the word should in Agency guidances means that something is suggested or recommended, but 
not required.  
 
 
II.  BACKGROUND 
 
A companion diagnostic is an in vitro diagnostic device that provides information that is 
essential for the safe and effective use of a corresponding therapeutic product.  The use of a 
companion diagnostic with a therapeutic product is stipulated in the instructions for use in the 
labeling of both the companion diagnostic and the corresponding therapeutic product, including 
labeling of any generic4 version of the therapeutic product.5   
 
In oncology, precision medicine (also referred to as personalized medicine) aims to match 
therapeutic products to those patients (and only those patients) who will positively respond to 
that therapeutic product, to maximize benefits and minimize risks from the therapeutic product 
received.  Precision oncology therefore depends on 1) understanding the molecular 
pathophysiology of cancer and 2) the ability of companion diagnostics to accurately and reliably 
detect and measure molecular biomarkers.  These companion diagnostics inform both the 
development and the approved use of therapeutic products.   
 
Trials designed to support approval of a specific therapeutic product and a specific companion 
diagnostic have led to companion diagnostic labels that reference only a specific therapeutic 
product(s).  Such specificity in labeling can limit a potentially broader use of a companion 
diagnostic that may be scientifically appropriate.  In some cases, there are multiple companion 
diagnostics approved by FDA to detect the same molecular alterations in the same specimen 
type.  Similarly, in some cases, there are multiple FDA-approved therapeutics within a specific 
group of oncology therapeutic products.6  This results in, in some cases, not all of the oncology 
                                                 
4 For the purpose of this guidance, the term generic refers to a new drug product approved in an abbreviated new 
drug application (ANDA) submitted under section 505(j) of the Federal Food, Drug, and Cosmetic Act. 
5 FDA has previously issued guidance to define companion diagnostics, clarify the goal of contemporaneous 
approval of the therapeutic product and the companion diagnostic, provide guidance on premarket regulatory 
pathways and FDAs regulatory enforcement policy, and describe statutory and regulatory requirements for labeling; 
FDAs Guidance for Industry and FDA Staff: In Vitro Companion Diagnostic Devices. 
6 The specific group refers to the indication that the therapeutic products have in common which is captured in the 
therapeutic products labeling (including sections other than the indications and usage section).  A therapeutic 
product could have other indications than those within the specific group that a companion diagnostic is labeled to 
identify.  Likewise, a companion diagnostic could have other intended uses outside of the specific group of oncology 
therapeutic products or for other specimen types.  Broader labeling may be appropriate regarding the indications that 
the specific group of oncology therapeutic products have in common.   
  2  Contains Nonbinding Recommendations 
 
therapeutic products in a specific group being included on all of the labels of approved 
companion diagnostics to detect molecular alteration(s) that define the specific group (see Table 
1).  FDA is concerned that the current situation is not optimal for patient care because a clinician 
may need to order a different companion diagnostic (i.e., one that includes other therapeutic 
products on the label), obtain an additional biopsy(ies) from a patient, or both, to have additional 
therapy treatment options.  FDA is interested in discussing with sponsors wishing to pursue 
labeling a companion diagnostic to reference a specific group of oncology therapeutic products, 
when the evidence would support expanding the indication. 
 
An example in precision oncology, which illustrates the issue regarding companion diagnostic 
labeling in oncology, is the identification of specific EGFR mutations in tumors of patients with 
NSCLC.  There are five FDA-approved therapeutic products indicated for the treatment of 
patients with NSCLC whose tumors have EGFR exon 19 deletions or exon 21 (L858R) 
substitution mutations as detected by an FDA-approved test: afatinib, gefitinib, erlotinib, 
osimertinib, and dacomitinib (see Table 1).7,8  However, the FDA-approved companion 
diagnostics that identify these specific mutations in EGFR in tissue samples are only indicated 
for a subset of the five FDA-approved therapeutic products.   
 
Table 1  FDA approved companion diagnostics labeled for identifying patients with NSCLC 
whose tumors have EGFR exon 19 deletions or exon 21 (L858R) substitution mutations and the 
associated therapeutic products listed on the companion diagnostic labels 
 
FDA-Approved  FDA-Approved Therapeutic Products  
Companion   
Diagnostics  Afatinib  Gefitinib  Erlotinib  Osimertinib  Dacomitinib 
Therascreen EGFR  X  X  -  -  X 
RGQ PCR Kit 
Cobas EGFR  -  X  X  X  - 
Mutation Test V2 
Oncomine Dx  -  X  -  -  - 
Target Test 
FoundationOne  X  X  X  X  - 
CDx 
 
While EGFR is just an example, it could be possible for companion diagnostics that are 
adequately validated to detect the biomarker(s) of interest and to identify appropriate patients for 
treatment to be indicated more broadly for use with a specific group of oncology therapeutic 
products.  In this example, the oncology community would be better served by a companion 
diagnostic that detects EGFR exon 19 deletions or exon 21 (L858R) substitution mutations 
                                                 
7 For purposes of this example, we are focusing on the indication described in the guidance.  However, examples of 
products in the illustrative example with indications that are other than the indication described in the illustrative 
example are 1) afatinib which, at the time of this guidance, is indicated for a broader population, i.e., those whose 
tumors have non-resistant epidermal growth factor receptor (EGFR) mutations as detected by an FDA-approved 
test and 2) the Cobas EGFR Mutation Test V2 which is also approved for identifying EGFR exon 19 deletions or 
exon 21 (L858R) substitution mutations in plasma specimens. 
8 EGFR exon 20 T790M alterations are excluded from the scope of this illustrative example.  
  3  Contains Nonbinding Recommendations 
 
indicated for identifying patients with NSCLC whose tumors have EGFR exon 19 deletions or 
exon 21 (L858R) substitution mutations and are suitable for treatment with a tyrosine kinase 
inhibitor approved by FDA for that indication.  This could enable greater flexibility for 
clinicians in choosing the most appropriate therapeutic product based on a patients biomarker 
status.  However, labeling for such a broader use is not as simple as just matching diagnostic 
targets with therapeutic targets.  Different diagnostics for the same target may utilize different 
cut-offs, filters, or other design features that impact the patient populations they identify and, 
consequently, the likelihood of a biomarker positive patient to respond to a given therapy.  Any 
potential differences should be evaluated to ensure it is clinically appropriate to take a broader 
labeling approach.  See section IV for considerations regarding broader labeling. 
 
 
III.  DEVELOPMENT AND LABELING OF COMPANION DIAGNOSTICS IN 
ONCOLOGY     
 
Some companion diagnostics in oncology could be developed in a way that results in labeling for 
a specific group of oncology therapeutic products.  Similarly, for sponsors seeking to broaden the 
labeling of already approved or cleared companion diagnostics, sponsors may submit a 
marketing application supplement in support of broader labeling (see section V).  These 
approaches will help ensure the resulting indication optimally facilitates clinical use.  This 
approach is consistent with FDAs labeling for in vitro diagnostic product regulations, which 
requires, among other things, the intended use or uses of the product9 be included in the label 
and labeling.  In addition, this approach aligns with FDAs guidance regarding therapeutic 
product labeling, which states that the therapeutic product labeling should specify use of an 
FDA approved or cleared IVD companion diagnostic device, rather than a particular 
manufacturers IVD companion diagnostic device.  This will facilitate the development and use 
of more than one approved or cleared IVD companion diagnostic device of the type described in 
the labeling for the therapeutic product.10    
 
When it is scientifically appropriate, FDA supports developers of companion diagnostics to 
develop their products (or pursue broader labeling for approved companion diagnostics) in a way 
that results in broader labeling for their products (i.e., for a specific group of oncology 
therapeutic products).  FDA acknowledges that such an approach may require collaboration with 
therapeutic product developers and encourages this to enable the companion diagnostic labeling 
to provide greater flexibility for clinicians in choosing the most appropriate therapeutic product 
based on a patients biomarker status.  Additional benefits of broader labeling in product 
development include 1) the applicability of the broader labeling to future oncology therapeutics 
in the specific group and 2) the ability to use a broadly labeled companion diagnostic in 
oncology therapeutic product development programs in the specific group.   
 
 
 
 
                                                 
9 21 CFR 809.10(a)(2) and 809.10(b)(2). 
10 FDAs Guidance for Industry and FDA Staff: In Vitro Companion Diagnostic Devices, page 11. 
  4  Contains Nonbinding Recommendations 
 
IV.  CONSIDERATIONS REGARDING BROADER LABELING 
 
The label and labeling for a companion diagnostic is required to specify its intended use (21 CFR 
809.10(a)(2) and 809.10(b)(2)).  Therefore, a companion diagnostic that is intended for use with 
a therapeutic product must specify the therapeutic product(s) for which it has been approved or 
cleared for use.  In some cases, however, if evidence is sufficient to conclude that the companion 
diagnostic is appropriate for use with a specific group of oncology therapeutic products, the 
intended use/indications for use should name the specific group, rather than each specific product 
within the group.   
 
FDA recommends that companion diagnostic developers consider a number of factors, including 
but not limited to those listed below, when determining whether their test could be developed, or 
the labeling for approved companion diagnostics could be revised through a supplement, to 
support a broader labeling claim such as use with a specific group of oncology therapeutic 
products (rather than listing an individual therapeutic product(s)).  In addition, these 
considerations include examples of when companion diagnostics may not be appropriate for 
broader labeling because such labeling could lead to incorrect identification of patients for 
therapeutic treatment.  These considerations or factors do not change the relevant regulatory 
standards for evaluating whether broader labeling for companion diagnostics should be approved 
or cleared, including whether any information to support such labeling meets the standard of 
valid scientific evidence under 21 CFR 860.7(c)(2).  When a companion diagnostic has been 
approved or cleared for use with a therapeutic product(s), a PMA supplement or new 510(k), as 
appropriate, containing the needed information, will be needed if the companion diagnostic 
manufacturer chooses to expand the companion diagnostic labeling to broaden the indication for 
use with a specific group of oncology therapeutic products.  Given considerations including, for 
example, evolving and complex biomarkers and potential device to device variation in 
identifying these biomarkers and evidence needed, we encourage sponsors considering 
development of a companion diagnostic for broader labeling to meet with CBER, CDRH, or 
CDER, in coordination with the Oncology Center of Excellence (OCE), as appropriate, early in 
development, to discuss.  Developers of approved companion diagnostics considering broader 
labeling should contact CDRH or CBER, as appropriate, to discuss (see section V). 
 
 
1.  Whether a specific group of oncology therapeutic products can be defined for which 
a companion diagnostic will identify an appropriate patient population for potential 
treatment.  A key issue for such development and labeling will be identifying the 
specific group of oncology therapeutic products to be included in the labeling for the 
companion diagnostic.  For the purposes of this guidance, a specific group of oncology 
therapeutic products are those approved for the same indications, including the same 
molecular alteration(s), such as mutation(s), amplification(s), and fusion(s)11 for which 
clinical evidence has been developed with at least one device for the same specimen type 
for each therapeutic product.  In some cases, the indications may be for different lines of 
treatment.  As demonstrated by the identification of the specific group in the illustrative 
example (see section II), the identification of the specific group will include the level of 
                                                 
11 See footnotes 6 and 7 for additional information regarding the indication(s). 
  5  Contains Nonbinding Recommendations 
 
detail needed to identify an appropriate patient population and will be informed by the 
clinical and analytical evidence supporting the companion diagnostic indication.  
Developers of companion diagnostics should discuss the specific group of oncology 
therapeutic products with CBER, CDRH, or CDER, in coordination with OCE, as 
appropriate, early in development.   
 
FDA recognizes that as science evolves, our understanding of the mechanism of action of 
therapeutic products and of the interaction between therapeutic products and biomarkers 
will evolve, which may impact how specific groups of oncology therapeutic products are 
defined.  For example, the definition of wildtype for RAS, which is included in the 
labels of drugs such as cetuximab and panitumumab, has significantly changed over time.   
 
 
2.  Whether there is a detailed understanding of a) the mechanism of action of the 
specific group of oncology therapeutic products being considered for use with the 
companion diagnostic and b) the interaction between the therapeutic products and 
the biomarker(s), at the molecular alteration level, detected by the companion 
diagnostic.  The mechanism of action for a therapeutic product can be influenced by a 
number of factors, including the molecular alteration itself.  Therapeutic products may 
target different areas of a protein and can therefore be differentially influenced by, for 
example, the resultant tertiary structure changes from various amino acid substitutions.  
Similarly, a therapeutic product may target a unique genetic alteration or be influenced by 
surrounding genetic mutations.  Additionally, an understanding of the prevalence of the 
biomarker in the population or the relationship between the expression or level of the 
biomarker and the therapeutic response is important and can greatly influence whether it 
would be scientifically appropriate to consider a broader labeling approach.  Having a 
detailed understanding of the mechanism of action for the therapeutic is critical to 
support broader labeling identifying the specific group of therapeutics for which a 
companion diagnostic could be safely and effectively used. 
 
A detailed understanding of the interaction between the therapeutics and biomarker could 
be achieved through clinical studies, retrospective analyses of clinical data, or both, 
supported or extended by nonclinical information to support approval or clearance of 
broader labeling for the companion diagnostic.  The sponsor of the companion diagnostic 
could use sources of valid scientific evidence as described in 21 CFR 860.7(c)(2), such as 
the therapeutic product labeling or therapeutic product study data or peer-reviewed 
scientific literature, or the sponsor could perform clinical studies as needed.  For 
example, EGFR exon 19 deletions and exon 21 (L858R) substitution mutations are 
known to upregulate EGFR phosphorylation and respond to treatment with tyrosine 
kinase inhibitors of EGFR based on functional studies.12  Special care, however, should 
be taken to identify aspects of biomarkers which would exclude them from being 
                                                 
12 Lynch TJ, Bell DW, Sordella R, et. al., 2004, Activating Mutations in the Epidermal Growth Factor Receptor 
Underlying Responsiveness of Non-Small-Cell Lung Cancer to Gefitinib, NEJM, 350(21): 2129-39.  Pao W, Miller 
V, Zakowski M, et. al., 2004, EGF Receptor Gene Mutations are Common in Lung Cancers from Never Smokers 
and are Associated with Sensitivity of Tumors to Gefitinib and Erlotinib, PNAS, 101(36): 13306-11.  
  6  Contains Nonbinding Recommendations 
 
included in a labeled use with a group of oncology therapeutics.  For example, many 
mutations in EGFR exon 20 are tyrosine kinase inhibitor resistant (e.g., EGFR T790M).   
 
 
3.  Whether there is sufficient clinical experience with at least two therapeutic products 
for the same biomarker-informed indications.  The sponsor of the companion 
diagnostic could utilize currently available information, such as that published in peer-
reviewed literature, or perform new clinical studies, if necessary, to show that there is 
sufficient and consistent clinical experience with the group of oncology therapeutic 
products for the same biomarker-informed indications.  There should generally be 
experience with at least two FDA-approved therapeutic products that would comprise the 
group that the broader companion diagnostic indication would apply to.  For example, 
afatinib, erlotinib, gefitinib, osimertinib, and dacomitinib are all indicated for the 
treatment of patients with NSCLC whose tumors have EGFR exon 19 deletions or exon 
21 (L858R) substitution mutations, so they will all fall under one specific group (tyrosine 
kinase inhibitor indicated for the treatment of patients with NSCLC whose tumors have 
EGFR exon 19 deletions or exon 21 (L858R) substitution mutations).  Also, it would not 
be appropriate to include therapeutic products in this specific group that only target 
resistant mutations, such as EGFR T790M and C797S, for which there may not be 
sufficient or consistent clinical experience.   
 
 
4.  Whether analytical validity of the companion diagnostic has been demonstrated 
across the range of biomarkers that inform the indication.  Analytical validity is the 
ability of a companion diagnostic to perform as intended in terms of its sensitivity, 
specificity, accuracy, precision, and other relevant performance characteristics using a 
specified technical protocol.  Multi-marker companion diagnostics that already have an 
approval or clearance of a test for use with a therapeutic product in a potential group may 
be able to leverage the information in their already cleared or approved submission to 
demonstrate analytical validity of the companion diagnostic across the range of 
biomarkers that inform the indication, depending on which specific biomarkers and 
molecular alterations were included in analytical studies.  Future sponsors of companion 
diagnostics that do not already have an approval or clearance of a test for use with a 
therapeutic product in a potential group should demonstrate analytical validity of the 
companion diagnostic across the range of biomarkers that inform the indication, 
including the specific molecular alterations for which a companion diagnostic claim is 
being sought.  The sponsor should discuss with CDRH or CBER, as appropriate, to 
determine the criteria for analytical validation. 
 
It is important to ensure that the companion diagnostic can detect the specific molecular 
alteration(s) of interest that would identify which patients would benefit from the 
therapeutic products that are included in the defined group.  Using a test that is validated 
to detect the specific analyte(s) of interest is critical to ensuring that false negative or 
false positive results are not driving clinical decisions or therapeutic choices.  Further, 
since technologies used to detect a biomarker can vary widely with significant 
performance differences between them, differences in technology should be considered 
  7  Contains Nonbinding Recommendations 
 
as some molecular alterations might not be equally detectable by every technology.  For 
example, a non-trivial difference in discordance rate between next generation 
sequencing-based mutation profiling and immunohistochemistry could lead to differences 
in the number of patients identified as biomarker positive depending on the technology 
used.   
 
 
5.  Whether clinical validity of the companion diagnostic has been demonstrated with 
the therapeutic products in the disease of interest.  Clinical validity is the ability of a 
companion diagnostic to identify, measure, or predict the presence or absence of a 
clinical condition or predisposition for which the companion diagnostic is intended (i.e., 
the companion diagnostics ability to predict treatment responses or to select patients for 
the treatment).  Companion diagnostics that already have an approval or clearance of a 
test for use with a therapeutic product in a potential group can generally leverage the 
information in their already cleared or approved submission to demonstrate clinical 
validity of the companion diagnostic with the other therapeutic products in the disease of 
interest.  Future sponsors for companion diagnostics that do not already have an approval 
or clearance of a test for a therapeutic product in a potential group could perform, for 
example, concordance studies with a previously approved companion diagnostic for that 
indication to demonstrate high agreement, or prospectively-defined retrospective sample 
analyses to demonstrate comparable clinical performance (i.e., that the drug efficacy in 
the follow-on companion diagnostic positive or negative population is similar to that in 
the positive or negative population for the approved or cleared companion diagnostic).  
Alternatively, the sponsor could, for example, choose to do a clinical study establishing 
the link between the result of the companion diagnostic and patient outcomes for that 
indication.    
 
In an evaluation of clinical validity, the defined cut-off for a specific companion 
diagnostic is important to consider when assessing whether broader labeling is 
appropriate.  For example, a challenge with gene expression tests is that they may have 
differing thresholds by which a tumor sample is called positive or negative in a specimen.  
These assays may also have their own scoring algorithm and method of measuring cells 
which may impact what is needed regarding clinical validation.  For companion 
diagnostics that detect the same marker of interest and have similar analytical 
performance, different cut-offs may identify different groups of patients.  A cut-point that 
is set too high could mean that patients will be determined to not be candidates for a 
therapeutic or the cut-point may be too low and a patient be put on a therapeutic course 
that confers limited or no benefit.  Differing thresholds need to be resolved, for example 
during the performance concordance testing and analysis.  
 
We encourage the sponsor to discuss with CDRH or CBER, as appropriate, to determine 
the criteria for clinical validation to support broader labeling.  
 
 
  8  Contains Nonbinding Recommendations 
 
V.  PROCESS FOR BROADENING LABELING FOR APPROVED OR CLEARED 
COMPANION DIAGNOSTICS 
 
For companion diagnostics that may be appropriate for broader labeling that describes use with a 
specific group of oncology therapeutic products (rather than listing individual therapeutic 
product names), the companion diagnostic developer should contact CDRH or CBER, as 
appropriate, to discuss, using the appropriate approval or clearance pathway.13  Such 
submissions should generally include information justifying that the diagnostic can be used with 
a specific group of oncology therapeutic products and valid scientific evidence under 21 CFR 
860.7(c)(2) to support the broader labeling claim for the companion diagnostic, in accordance 
with appropriate requirements for approval or clearance.   
 
For providers and other stakeholders reference, FDA maintains a website that includes a list of 
cleared or approved companion diagnostic devices (in vitro and imaging tools) and the 
therapeutic product(s) stipulated in the instructions for use.  FDA will include on this website 
details of any in vitro companion diagnostic device that is approved for use with a specific group 
of oncology therapeutic products, including the names of the therapeutic products within the 
specific group.14   
 
A companion diagnostic sponsor that submits a PMA supplement or new 510(k), as appropriate, 
requesting FDA approval or clearance for a broader labeling claim should include in the 
proposed label the relevant specific group of oncology therapeutic products and a reference to 
FDAs website for the most current information on the therapeutic products in the group.   
                                                 
13 Companion diagnostic developers should submit a PMA supplement or a new 510(k), as appropriate.  If 
developers have specific questions, they can also submit a pre-submission request through which developers may 
obtain information concerning the appropriate submission.  See FDAs Guidance for Industry and FDA Staff: 
Requests for Feedback and Meetings for Medical Device Submissions: The Q-Submission Program, May 2019, 
available at:  https://www.fda.gov/regulatory-information/search-fda-guidance-documents/requests-feedback-and-
meetings-medical-device-submissions-q-submission-program. 
14 The specific group of oncology therapeutic products and the therapeutic products will be included on the 
following webpage - 
https://www.fda.gov/medicaldevices/productsandmedicalprocedures/invitrodiagnostics/ucm301431.htm. 
  9