Contains Nonbinding Recommendations
Policy for Coronavirus Disease-2019 
Tests (Revised)*
Guidance for Developers and
Food and Drug Administration Staff
Document issued January 12, 2023.
This document supersedes Policy for Coronavirus Disease-2019 Tests During 
the Public Health Emergency (Revised): Guidance for Developers and
Food and Drug Administration Staff issued September 27, 2022.
U.S. Department of Health and Human Services
Food and Drug Administration
Center for Devices and Radiological Health
*This is the seventh edition of this guidance, which originally issued February 29, 2020, and was 
subsequently revised on March 16, May 4, May 11, 2020, November 15, 2021, and September 
27, 2022.
1 Contains Nonbinding Recommendations
Preface
Public Comment
Comments may be submitted at any time for Agency consideration.  Submit written comments to 
the Dockets Management Staff (HFA-305), Food and Drug Administration, 5630 Fishers Lane, 
Rm. 1061, Rockville, MD 20852. Submit electronic comments to https://www.regulations.gov.  
All comments should be identified with the docket number FDA-2020-D-0987 and complete title 
of the guidance in the request.
Additional Copies
Additional copies are available from the FDA webpage titled COVID-19-Related Guidance 
Documents for Industry, FDA Staff, and Other Stakeholders, available at 
https://www.fda.gov/emergency-preparedness-and-response/mcm-issues/covid-19-related-
guidance-documents-industry-fda-staff-and-other-stakeholders, and the FDA webpage titled 
Search for FDA Guidance Documents, available at https://www.fda.gov/regulatory-
information/search-fda-guidance-documents.  You may also send an e-mail request to CDRH-
Guidance@fda.hhs.gov to receive an additional copy of the guidance.  Please include the 
document number GUI00020010 and complete title of the guidance in the request.
Questions
For questions about this document, contact CDRH-EUA-Templates@fda.hhs.gov.
2 Contains Nonbinding Recommendations
Table of Contents
I.  Introduction .......................................................................................................................... 4 
II.  Background .......................................................................................................................... 5
III.  Scope .................................................................................................................................... 6
IV.  Policy ................................................................................................................................... 7
A.  Review of EUA Requests for COVID-19 Tests .............................................................. 7
B.  State Authorization of High-Complexity CLIA-Certified Laboratories .......................... 8
C.  Distribution and Offering of SARS-CoV-2 Diagnostic and Serology Tests During FDA 
Review ...................................................................................................................................... 10
(1)  FDA Review of EUA Requests .................................................................................. 10
(2)  Recommendations Regarding Test Reports and Other Information for Tests Offered 
During FDA Review of EUA Requests ................................................................................ 11
D.  Modifications to EUA-Authorized Diagnostic COVID-19 Tests .................................. 11
(1)  Modifications Made After Issuance of this Updated Guidance ................................. 12
(2)  Certain Modifications Made Before Issuance of this Updated Guidance .................. 13
V.  Validation ........................................................................................................................... 14
VI.  Availability of EUA Templates and Inquiries Regarding Validation ................................ 15
3 Contains Nonbinding Recommendations
Policy for Coronavirus Disease-2019 
Tests (Revised)
Guidance for Developers and Food 
and Drug Administration Staff
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 staff 
or Office responsible for this guidance as listed on the title page. 
I.  Introduction
FDA plays a critical role in protecting the United States from threats such as emerging infectious 
diseases, including the Coronavirus Disease 2019 (COVID-19) pandemic. FDA is committed to 
providing timely guidance to support response efforts to this pandemic. 
FDA is issuing this guidance to provide FDAs review priorities and enforcement policies 
regarding novel coronavirus (COVID-19) tests. Rapid detection of COVID-19 cases in the 
United States requires wide availability of testing to control the spread of this highly contagious 
infection. 
The policies in this guidance are intended to remain in effect only for the duration of the 
declaration under section 564 of the Federal Food, Drug, and Cosmetic Act (FD&C Act) by the 
Secretary of Health and Human Services (HHS) on February 4, 2020, declaring that 
circumstances exist justifying the authorization of emergency use of in vitro diagnostics for 
detection and/or diagnosis of the novel coronavirus (2019-nCoV).1FDA continues to assess the 
evolving situation and intends to update this guidance as appropriate.
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 guidance means that something is suggested or recommended, 
but not required.
1 See 85 FR 7316; available at https://www.federalregister.gov/documents/2020/02/07/2020-02496/determination-
of-public-health-emergency. 
4 Contains Nonbinding Recommendations
II.  Background
There is currently a pandemic of respiratory disease caused by a novel coronavirus. The virus has 
been named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the disease it 
causes has been named Coronavirus Disease 2019 (COVID-19). On January 31, 2020, the 
Secretary of HHS issued a declaration of a public health emergency under section 319 of the 
Public Health Services Act related to COVID-19 and mobilized the Operating Divisions of 
HHS.2 On February 4, 2020, the Secretary of HHS issued a declaration that circumstances exist 
justifying the authorization of emergency use of in vitro diagnostics for detection and/or 
diagnosis of SARS-CoV-2 based on the HHS Secretarys public health emergency determination 
under section 564(b)(1)(C) of the FD&C Act.3 In addition, on March 13, 2020, the President 
declared a national emergency in response to COVID-19.4  
Under section 564 of the FD&C Act, the FDA Commissioner may authorize the use of 
unapproved medical products, or unapproved uses of approved medical products, in certain 
emergency circumstances, after the HHS Secretary has made a declaration of emergency or 
threat justifying authorization of emergency use, to diagnose, treat, or prevent serious or life-
threatening diseases or conditions caused by chemical, biological, radiological, and nuclear 
(CBRN) threat agents when certain criteria are met. The Emergency Use Authorization (EUA) 
authorities allow FDA to help strengthen the nations public health protections against CBRN 
threats by facilitating the availability and use of medical countermeasures needed during certain 
public health emergencies.
As of August 15, 2022, FDA has issued EUAs for more than 439 tests for COVID-19, including 
more than 354 diagnostic and 85 serology or other immune response tests. Further, two 
molecular diagnostic COVID-19 tests have been granted marketing authorization through the 
traditional device premarket review pathways. In the context of a public health emergency 
involving pandemic infectious disease, it is critically important that tests are validated because 
false results not only can negatively impact the individual patient but also can have a broad 
public health impact. False positive results for diagnostic tests, for example, can lead to 
unnecessary quarantine and potential further spread when presumed positive individuals are 
quarantined together, wasted contact tracing and testing resources, and delay in accurate 
diagnosis and appropriate treatment for the individual. False negative results can lead to lack of 
appropriate treatment for the individual and further spread of the disease.
2 Secretary of Health and Human Services, Determination that a Public Health Emergency Exists (originally issued 
on Jan. 31, 2020, and subsequently renewed), available at 
https://www.phe.gov/emergency/news/healthactions/phe/Pages/default.aspx.
3 85 FR 7316; available at https://www.federalregister.gov/documents/2020/02/07/2020-02496/determination-of-
public-health-emergency.
4 Proclamation on Declaring a National Emergency Concerning the Novel Coronavirus Disease (COVID-19) 
Outbreak (Mar. 13, 2020), available at https://trumpwhitehouse.archives.gov/presidential-actions/proclamation-
declaring-national-emergency-concerning-novel-coronavirus-disease-covid-19-outbreak/. On February 24, 2021, 
there was a Presidential Declaration continuing the national emergency concerning the COVID-19 pandemic beyond 
March 1, 2021. See Continuation of the National Emergency Concerning the Coronavirus Disease 2019 (COVID-
19) Pandemic (February 24, 2021), available at https://www.federalregister.gov/documents/2021/02/26/2021-
04173/continuation-of-the-national-emergency-concerning-the-coronavirus-disease-2019-covid-19-pandemic.
5 Contains Nonbinding Recommendations
Previous versions of this guidance described policies regarding the distribution and offering of 
certain tests for clinical use prior to or without an EUA. These policies were issued to help 
quickly increase availability of tests in the early stages of the pandemic. Unless and until an 
EUA is issued that authorizes additional testing environments for a specific test, under the 
Clinical Laboratory Improvement Amendments (CLIA), section 353 of the Public Health Service 
Act (42 USC 263a), use of that test is limited to laboratories that are certified under CLIA, and 
meet the requirements to perform tests of high complexity, and at the point-of-care (POC) when 
covered by such a laboratorys CLIA certificate. Throughout this guidance, references to high-
complexity CLIA-certified laboratories are referring to laboratories that are certified under 
CLIA and meet the requirements to perform tests of high complexity. These policies did not 
apply to at-home tests or tests with home specimen collection. 
FDA has updated these policies when appropriate in response to the changing landscape of this 
pandemic. The previous update on November 15, 2021, explained FDAs intent to review EUA 
requests for certain types of tests that FDA believed would be most beneficial at that stage of the 
pandemic. In addition, in the November 15, 2021, version, FDA revised the previous 
enforcement policies to reflect that, at that stage of the pandemic, the Agency generally expected 
COVID-19 tests to have been issued an EUA prior to the tests being distributed or offered.
FDA has continued to closely monitor the COVID-19 testing landscape and believes it is again 
appropriate to update its policies to reflect the current needs of the pandemic. As explained 
throughout this guidance, FDA intends to review the EUA requests for a small subset of tests 
based on the review priorities described in section IV.A. Traditional marketing pathways remain 
available to all developers and FDA encourages developers of tests that fall outside the scope of 
the priorities outlined in this guidance to pursue those routes. In sum, in the September 27, 2022, 
update, FDA revised this guidance to update the types of COVID-19 tests for which the Agency 
intends to review EUA requests, to discuss the use of the traditional premarket review pathways 
for other types of COVID-19 tests for which the Agency does not intend to review EUA 
requests, and to make minor updates to the enforcement policies. In the current version of this 
guidance, FDA has revised the duration for which the policies in this guidance are intended to 
remain in effect.
III.  Scope
This guidance applies to diagnostic and serology tests for COVID-19.5 The policies and 
recommendations described in this guidance are intended to facilitate availability of tests for 
5 Throughout this guidance, the term diagnostic test is generally used to refer to molecular or antigen tests, both of 
which can be used to diagnose infection with the SARS-CoV-2 virus. Diagnostic tests may be designed for use in 
various settings, such as in a CLIA-certified laboratory, at the point of care at a site covered by a laboratorys CLIA 
certificate, or at home.  Screening tests, which are used for testing individuals without symptoms or other reasons to 
suspect COVID-19, are a subset of diagnostic tests. Molecular tests detect the presence of viral RNA and antigen 
tests detect the presence of viral proteins that are part of the SARS-CoV-2 virus. There may also be diagnostic tests 
that incorporate different technologies, such as breath tests, that have a reasonable expectation of technical and 
clinical success. While the principles in this guidance are generally still applicable to such tests, there are fewer 
available, so different approaches may be appropriate. Therefore, FDA recommends that developers of such tests 
contact FDA at CDRH-EUA-Templates@fda.hhs.gov to discuss the best approach for their test. The terms 
6 Contains Nonbinding Recommendations
COVID-19 that FDA believes will be most beneficial at the current stage of the public health 
emergency. 
FDA notes that the enforcement policies in this guidance do not address medical device reporting 
(MDR) under 21 CFR Part 803 for tests offered prior to authorization as described in the 
guidance. Developers offering such tests are expected to comply with applicable MDR 
requirements, including reporting of medical device events that reasonably suggest that their 
device may have caused or contributed to a death or serious injury, and malfunctions that would 
be likely to cause or contribute to a death or serious injury if they were to recur. Moreover, 
unless and until an EUA is issued that authorizes additional testing environments for a specific 
test, under CLIA, use of that test is limited to high-complexity CLIA-certified laboratories, 
including testing at the point-of-care when the site is covered by the laboratorys CLIA 
certificate for high complexity testing.   
IV.  Policy 
A.  Review of EUA Requests for COVID19 Tests 
The issuance of an EUA is discretionary. FDAs decision to review and process an EUA request, 
and ultimately issue an EUA if the relevant statutory criteria are met, is based on a 
determination, on a case-by-case basis, that such action is necessary to protect the public health 
in an emergency. It is an authorization that the government may issue when necessary to 
protect the public health in an emergency (see section 564(a)(1) of the FD&C Act (21 U.S.C. 
360bbb-3(a)(1)), which states, in relevant part, subject to the provisions of this section, the 
Secretary may authorize the introduction into interstate commerce...a drug, device, or biological 
product intended for use in an actual or potential emergency). FDAs January 2017 guidance, 
Emergency Use Authorization of Medical Products and Related Authorities, 6 describes factors 
that FDA intends to use in its prioritization of EUA requests, such as the public health need for 
the product, the availability of the product, the availability and adequacy of the information 
concerning the likelihood that the product may be safe and effective in preventing, treating, or 
diagnosing the condition, and whether the product is included in government stakeholder 
stockpiles. 
Given the need to address urgent public health priorities, FDA has and continues to prioritize 
among the EUA requests it receives for COVID-19 tests. 
At this stage of the pandemic, FDA intends to prioritize its review of EUA requests and 
supplemental EUA requests from experienced developers7 for diagnostic tests that are likely to 
serology or antibody tests are generally used to refer to tests that detect antibodies to the SARS-CoV-2 virus. 
Because the antibodies are part of the bodys immune response to exposure and not the virus itself, such testing 
cannot be used fordiagnosis of acute infection. 
6 See https://www.fda.gov/regulatory-information/search-fda-guidance-documents/emergency-use-authorization-
medical-products-and-related-authorities. 
7 For the purposes of this guidance, experienced developers refers to developers who have interacted with FDA 
through a successful EUA request or have similar experience. FDA has interacted with over 1,000 test developers 
through the EUA and pre-EUA processes during the SARS-CoV-2 pandemic. The Agency has found that EUA 
7 Contains Nonbinding Recommendations
have a significant public health benefit (e.g., employ innovative technology) or are likely to 
fulfill an unmet need (e.g., diagnosing infection with a new variant or subvariant).
FDA generally intends to focus its review on EUA requests and supplemental EUA requests for 
tests that are within these priorities.8 In addition to the above priorities, FDA also intends to 
focus its review on EUA requests that are from or supported by a U.S. government stakeholder,9
such as tests funded by the Biomedical Advanced Research and Development Authority 
(BARDA) or the National Institutes of Healths Rapid Acceleration of Diagnostics (RADx). 
FDA intends to notify test developers of its intent by email if FDA declines to review or 
otherwise decides not to authorize a test/modification in an EUA request or supplemental EUA 
request.
In general, FDA believes these priorities are appropriate to address the public health needs at the 
current stage of the public health emergency based on the available information and may adjust 
these priorities as public health needs change. Specifically, there is generally sufficient 
availability of authorized high-throughput laboratory-based diagnostic tests intended for use with 
pooled samples and authorized home-use antigen tests that are available for over the-counter 
(OTC) or prescription use. 
FDA believes that the number of EUA requests that fall within FDAs current review priorities 
described in this guidance are likely limited and generally encourages developers to submit 
COVID-19 tests through traditional premarket review pathways. If you are unsure whether your 
test may be prioritized for review, we encourage you to reach out to CDRH-EUA-
Templates@fda.hhs.gov; however, at this stage, FDA strongly encourages developers of new 
tests and existing tests for which modifications are sought to pursue traditional pre-market 
pathways. 
B.  State Authorization of HighComplexity CLIACertified 
Laboratories 
Versions of this guidance prior to November 15, 2021, described a policy regarding States and 
territories that authorize laboratories within their State or territory to develop their own COVID-
19 tests and perform specimen testing, where the notification of SARS-CoV-2 test validation is 
not submitted to FDA and the laboratory does not submit an EUA request to FDA.
requests from inexperienced developers are more resource intensive to review. At this phase of the pandemic, and 
given our experiences to date, we believe that for COVID-19 tests, FDAs review resources are more impactful 
when working with experienced developers given the design and validation complexities associated with such tests. 
As a result, FDA intends to prioritize the review of EUA requests for tests from experienced developers.
8 Developers of tests that are not within these priorities should consider pursuing marketing authorization through a 
traditional premarket review pathway. Test developers are welcome to reach out to the team at CDRH-EUA-
Templates@fda.hhs.gov to discuss whether review of their EUA request may be prioritized. 
9 Prioritization of EUA requests from (or supported by) government stakeholders is discussed in the Guidance for 
Industry and Other Stakeholders: Emergency Use Authorization of Medical Products and Related Authorities, 
available at https://www.fda.gov/regulatory-information/search-fda-guidance-documents/emergency-use-
authorization-medical-products-and-related-authorities. 
8 Contains Nonbinding Recommendations
Under such policy, a State or territory choosing to authorize laboratories within that State or 
territory to develop and perform a test for COVID-19 would do so under authority of its own 
State law, and under a process that it established, and FDA did not intend to object to the use of 
such tests for specimen testing where the notification of SARS-CoV-2 test validation was not 
submitted to FDA and the laboratory did not submit an EUA request to FDA, and where instead 
the State or territory took responsibility for COVID-19 testing by laboratories in its State during 
the COVID-19 outbreak. This policy applied only to tests designed, developed, and used within a 
single, high-complexity, CLIA-certified laboratory. The policy did not apply to at-home tests or 
tests with home specimen collection, or any testing outside of a high-complexity CLIA-certified 
laboratory.10
In versions of this guidance prior to November 15, 2021, FDA requested that the State or 
territory notify us if it chose to use this flexibility to expedite COVID-19 testing.11 FDA 
indicated that it would not be reviewing the process adopted by the State or territory. FDA 
expected that such States and territories as part of their oversight process would require 
laboratories developing SARS-CoV-2 tests to validate those tests prior to use. FDA encouraged 
laboratories that developed and performed a test for COVID-19 that was authorized by a State or 
territory to notify FDA that they have started clinical testing by sending an email to that effect to 
CDRH-EUA-Templates@FDA.HHS.GOV, and provide information on testing capacity. 
In the November 15, 2021, version of this guidance, FDA revised this policy such that FDA no 
longer intended to apply the policy to any additional States or territories going forward.12 The 
FDA is maintaining the policy in Section IV.B. of the November 15, 2021, policy, without 
further revision. For the States and territories listed on the notification list on FDAs website 
prior to November 15, 2021, that are continuing to authorize laboratories within that State or 
territory to develop and perform a test for COVID-19, FDA does not intend to object to the use 
of such tests for specimen testing where notification of SARS-CoV-2 test validation is not 
submitted to FDA and the laboratory does not submit an EUA request to FDA, and where instead 
the State or territory takes responsibility. This policy applies only to tests designed, developed, 
and used within a single, high-complexity CLIA-certified laboratory. This policy does not apply 
to at-home tests or tests with home specimen collection, or any testing outside of a high-
complexity CLIA-certified laboratory.13
10 There are different risks associated with testing in different settings and different issues need to be addressed. For 
example, home collection raises several issues of importance, including whether the lay user can safely and properly 
collect the specimen, whether the components of the specimen transport media are safe for use in the home 
environment (because some may be toxic), proper shipment, and adequate stability of the specimen given the time 
lapse between collection and testing and the potential impact of shipping conditions (such as, if the specimen sits in 
a hot truck). Tests performed fully at home raise additional issues such as whether the lay user can safely and 
properly perform the test and read and accurately interpret the results.
11 A list of States and territories that have notified FDA under this policy is available on FDAs FAQ website at: 
https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/notifications-and-emergency-use-
authorizations-faqs-testing-sars-cov-2. 
12 A State or territory that believes there would be a particular benefit to the policy applying to the State or territory 
is welcome to reach out to FDA to discuss further by sending an email to CDRH-EUA-Templates@fda.hhs.gov.
13 As discussed in FN [8], there are different risks associated with testing in different settings and different issues 
need to be addressed.
9 Contains Nonbinding Recommendations
FDA notes that laboratories should be aware of requirements to report test results to appropriate 
federal, state, and local public health agencies in accordance with applicable federal, state, and 
local laws.14
C.  Distribution and Offering of SARSCoV2 Diagnostic and 
Serology Tests During FDA Review 
Previous versions of this guidance document described enforcement policies where FDA 
generally did not intend to object to developers distributing and offering certain tests prior to 
FDA authorization, as described in the policies. Those policies were updated in the November 
15, 2021, version of the guidance, and FDA is generally continuing those updated policies and 
clarifying them, as discussed below.
(1)  FDA Review of EUA Requests 
For the following tests, FDA does not intend to object to the continued distribution or offering of 
the test while FDA reviews the EUA request for the test:
 Tests on one of the notification lists15 on FDAs website at the time of issuance of 
this updated guidance; and,
 Laboratory developed tests (LDTs)16 offered following the HHS August 2020 
Web Statement entitled, Rescission of Guidances and Other Informal Issuances 
Concerning Premarket Review of Laboratory Developed Tests (August 2020 
HHS Announcement) and prior to November 15, 2021, where an EUA request 
was submitted to FDA as described in Section IV.C.2 of the November 15, 2021 
version of this guidance document.17
For tests described in this section, FDA intends to notify test developers by email if FDA 
declines to review, declines to issue, or otherwise decides not to authorize the test for any reason, 
including lack of response or a determination that there is a lack of adequate data to support 
authorization. If so notified, FDA generally expects developers to cease distributing, marketing, 
and offering their tests within 15 calendar days. Moreover, if FDA identifies a significant 
problem or concern with a test, based either on the provided information or external reports, 
FDA generally would expect the developer to take appropriate steps to address such problems, 
14 Under section 18115 of the CARES Act (Public Law 116-136), laboratories, including those in patient care 
settings operating under a CLIA Certificate of Waiver, Certificate of Compliance or Certificate of Accreditation, 
must report the results of COVID-19 tests to HHS or its designee, in such form and manner as the Secretary may 
prescribe, during the declared public health emergency. For additional information on the laboratory data reporting 
guidance and FAQs from HHS, please see:https://www.hhs.gov/coronavirus/testing/covid-19-diagnostic-data-
reporting/index.html.
15 https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/notifications-and-emergency-
use-authorizations-faqs-testing-sars-cov-2 
16 LDTs are typically considered tests that are designed, manufactured, and used within a single laboratory that is 
certified under CLIA and meets the requirements to perform tests of high complexity.
17 This does not apply to EUA requests for which FDA has already notified the test developer by email that FDA 
declines to review, declines to issue, or otherwise decides not to authorize the test for any reason, including lack of 
response or a determination that there is a lack of adequate data to support authorization. Developers of such tests 
were generally expected to cease distributing, marketing, and offering their tests within 15 calendar days of 
receiving such an email.  
10 Contains Nonbinding Recommendations
which could include conducting a recall of the test and/or notification concerning corrected test 
reports indicating prior test results may not be accurate.
 
(2)  Recommendations Regarding Test Reports and Other 
Information for Tests Offered During FDA Review of EUA 
Requests
FDA continues to recommend the following:
1.  Test reports should prominently disclose that the test has not been reviewed by FDA. 
Until the test is authorized by FDA, any statements in the test reports and other labeling 
that expressly state or imply that the test has been authorized by FDA would be false. 
Similarly, any statements in the test reports and other labeling that state or imply that 
EUA issuance or FDA authorization are imminent or pending could be misleading.  
2.  Developers should make publicly available on their website the instructions for use for 
the test and data about the tests performance characteristics, including a summary of 
assay performance. 
3.  Instructions for use and patient test reports for serology tests should include information 
that helps users and patients understand the test results, including the following:
  Negative results do not preclude acute SARS-CoV-2 infection. If acute infection is 
suspected, direct (i.e., diagnostic) testing for SARS-CoV-2 is necessary.
 Results from antibody testing should not be used to diagnose or exclude acute 
SARS-CoV-2 infection.
 Positive results may be due to past or present infection with non-SARS-CoV-2 
coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E. 
In addition, as noted in previous versions of this guidance and earlier in this updated guidance, 
unless and until an EUA is issued that authorizes additional testing environments for a specific 
test, under CLIA, use of that test is limited to high-complexity CLIA-certified laboratories, 
including testing at the POC when the site is covered by such a laboratorys CLIA certificate. 
D.  Modifications to EUAAuthorized Diagnostic COVID19 
Tests 
Throughout the course of the pandemic, FDA has issued various policies with respect to 
modifications and, as discussed further below, FDA is updating these policies. The policies in 
this section do not apply to at-home tests or tests with at-home specimen collection.
In order to provide transparency, when a developer is distributing or offering a test that is a 
modification of an EUA-authorized diagnostic test prior to or without authorization of the 
modified test, as discussed in this section, the recommendations in Section IV.C.2 of this updated 
guidance apply. FDA further recommends that the developer post data about the modified tests 
performance characteristics on the developers website, and that the instructions for use or test 
11 Contains Nonbinding Recommendations
protocol and the test reports accurately reflect the modification and prominently disclose that the 
test has been modified since authorization by FDA and that the modified test has not been 
reviewed by FDA. 
If FDA identifies a significant problem or concern with a modified test, based either on the 
provided information or external reports, that cannot be addressed in a timely manner, FDA 
generally would expect the developer to cease distribution, marketing and offering the modified 
test and address such problem, which could include conducting a recall of the modified test 
and/or notification concerning corrected test reports indicating prior test results may not be 
accurate.
(1)  Modifications Made After Issuance of this Updated Guidance 
In addition to the priorities above, FDA intends to review supplemental EUA requests that fulfill 
a condition of an EUA. For other supplemental requests, such as those that are beyond the 
priorities outlined above, FDA encourages developers to consider including the modification in a 
submission through a traditional premarket review pathway. In general, FDA expects such 
modified tests to be authorized under an EUA or pursuant to a traditional premarket review 
pathway before being distributed or offered.   
When a high-complexity CLIA-certified laboratory is modifying an authorized COVID-19 
molecular diagnostic test, including one for which such laboratory is not the developer of the 
original, EUA-authorized test, and the modifications do not change the indication for use set 
forth in the EUA (e.g., including new/different extraction kits or instruments that would not be 
expected to change the indication for use) and do not change the analyte specific reagents (e.g., 
the modifications do not change the PCR primers and/or probes),18 FDA does not intend to 
object to implementation of the modification to the diagnostic test without notification to FDA or 
a new or amended EUA where the laboratory has validated the modification and confirmed that 
the performance of the modified test is equivalent to the performance of the authorized test, and 
use of the test is limited to the high-complexity CLIA-certified laboratory in which the 
modification was made.19     
In such cases, where the laboratory modifying and performing the test is not the developer of the 
original, EUA-authorized test, FDA encourages the laboratory to collaborate with the developer 
of the authorized test so that validation data supporting the modifications can be submitted by the 
original developer to FDA in a supplemental EUA request or incorporated into a future 
submission through the traditional premarket review pathways.    
18 Other modifications, including new specimen types, test settings (e.g., point-of-care, home testing), and new 
patient populations (e.g., asymptomatic individuals), among others, do not fall under this policy.
19 FDA generally considers equivalent performance to be where the LoD of the modified test (using the same 
validation material used in the LoD study described in the authorized tests Instructions For Use (IFU)) is within 3x 
of the LoD established in the authorized tests IFU or that the LoD of the modified test is within 3x of the LoD of 
the authorized test in a direct comparison LoD study.
12 Contains Nonbinding Recommendations
(2)  Certain Modifications Made Before Issuance of this Updated 
Guidance
Under previous versions of this guidance, when a commercial manufacturer made certain 
modifications to its EUA-authorized COVID-19 diagnostic test, and where validation data 
supporting the modification had been submitted in a supplemental EUA request, FDA stated that 
it did not intend to object to implementation of the modification while FDA conducted its 
review, except for modifications to add specimen types that have not been previously authorized 
with another test of the same technology. For such modifications made and implemented as 
discussed in the policies in the previous version of the guidance, FDA does not intend to object 
to such commercial manufacturers continuing to implement the modification while FDA 
conducts its review.  
Under previous versions of the guidance, when a high-complexity CLIA-certified laboratory 
modified an EUA-authorized COVID-19 diagnostic test20 prior to November 15, 2021, for use 
with a new specimen type, where the new specimen type has been previously authorized for 
another test of the same technology21 and where the laboratory had validated the test for the new 
specimen type, FDA stated that it did not intend to object to the use of such a modified test 
without notification to FDA or a new or amended EUA. For all other types of modifications 
made by the high-complexity CLIA-certified laboratory prior to November 15, 2021, for an 
EUA-authorized COVID-19 diagnostic test, in previous versions of the guidance, FDA stated 
that it did not intend to object to the use of the test by high-complexity CLIA-certified 
laboratories, without notification to FDA or a new or amended EUA, where the modified test is 
validated using a bridging study to the EUA-authorized test. 
For high-complexity CLIA-certified laboratories that modified an authorized COVID-19 
molecular diagnostic test after November 15, 2021, but before issuance of the September 27, 
2022, version of the guidance, including one for which such laboratory is not the developer of 
the original, EUA-authorized test, and the modifications do not change the indication for use set 
forth in the EUA (e.g., including new/different extraction kits or instruments that would not be 
expected to change the indication for use) and do not change the analyte specific reagents (e.g., 
the modifications do not change the PCR primers and/or probes),22 FDA stated that it did not 
intend to object to implementation of the modification to the diagnostic test without notification 
to FDA or a new or amended EUA where the laboratory has validated the modification and 
confirmed that the performance of the modified test is equivalent to the performance of the 
authorized test, and use of the test is limited to the high-complexity CLIA-certified laboratory in 
which the modification was made.23
20 This applies to modifications to any EUA-authorized diagnostic test, including a laboratorys own test with an 
EUA or a purchased kit from a commercial manufacturer with an EUA, but does not apply to modifications of 
authorized home collection kits.
21 For the purposes of this guidance, all nucleic acid amplification tests are considered to have the same technology.
22 Other modifications, including new specimen types, test settings (e.g., point-of-care, home testing), and new 
patient populations (e.g., asymptomatic individuals), among others, do not fall under this policy.
23 FDA generally considers equivalent performance to be where the LoD of the modified test (using the same 
validation material used in the LoD study described in the authorized tests Instructions For Use (IFU)) is within 3x 
of the LoD established in the authorized tests IFU or that the LoD of the modified test is within 3x of the LoD of 
the authorized test in a direct comparison LoD study.
13 Contains Nonbinding Recommendations
For such modifications made and implemented by high-complexity CLIA-certified laboratories 
as discussed in the policies in the previous versions of the guidance, FDA does not intend to 
object to such laboratories continuing to offer any of those modified tests.
In such cases, where the laboratory performing the modified test is not the developer of the 
original, EUA-authorized test, FDA encourages the laboratory to share its validation data with 
the developer of the original, EUA-authorized test so that the developer of the original, EUA-
authorized test can use the validation data in support of a supplemental EUA request to add the 
modification or can incorporate it into a future submission through the traditional premarket 
review pathways.   
V.  Validation
All clinical tests should be validated using clinical specimens and an appropriate comparator test 
prior to use. 
In the context of a public health emergency, it is critically important that tests be validated prior 
to use because false results not only can negatively impact the individual patient but also can 
have a broad public health impact. However, FDA also generally accepts a lower level of 
evidence of validation for an EUA than for traditional premarket review pathways. FDA has 
provided recommendations regarding testing that should be performed to ensure analytical and 
clinical validity to the level of evidence expected for an EUA, including descriptions of 
appropriate comparators for different types of tests, in the EUA templates available through 
download from our website.24 Depending on the characteristics of a developers test, additional 
validation studies may be recommended. 
Because the level of evidence required for authorization under traditional premarket review 
pathways is higher than that required for an EUA, the recommendations in the EUA templates 
may not be sufficient for developers seeking marketing authorization of their tests through 
traditional premarket review pathways. FDA can provide recommendations specific to a test 
developers situation through inquiries to CDRH-EUA-Templates@fda.hhs.gov or through pre-
submission interactions.25  
Developers can use alternative approaches. FDA encourages developers to discuss any 
alternative technological approaches to validating their test with FDA through CDRH-EUA-
Templates@FDA.HHS.GOV. 
24 See https://www.fda.gov/medical-devices/coronavirus-disease-2019-covid-19-emergency-use-authorizations-
medical-devices/in-vitro-diagnostics-euas. 
25 See FDA Guidance document Requests for Feedback and Meetings for Medical Device Submissions: The Q-
Submission Program, available at: https://www.fda.gov/regulatory-information/search-fda-guidance-
documents/requests-feedback-and-meetings-medical-device-submissions-q-submission-program. 
14 Contains Nonbinding Recommendations
Additionally, FDA continues to expect certain serology tests to be independently evaluated by 
NIH/NCI,26 prior to authorization, when requested by the FDA. When performed, this additional 
testing can assist FDA in determining whether the EUA issuance criteria in section 564 of the 
FD&C Act have been met and whether FDA should authorize the test. This independent 
evaluation may also be used to assist FDA in determining whether the criteria for marketing 
authorization have been met for tests submitted through traditional premarket review pathways.   
VI.  Availability of EUA Templates and Inquiries Regarding 
Validation 
FDA has made available through download from our website27 a series of templates that 
developers may choose to use to facilitate the preparation and submission of an EUA request for 
various types of COVID-19 tests. The templates reflect FDAs current thinking on validation 
recommendations for SARS-CoV-2 tests and the data and information that developers should 
submit to facilitate the EUA process. The templates provide information and recommendations, 
and FDA plans to update them as appropriate as more is learned about COVID-19 and more 
experience is gained with the EUA process for the various types of COVID-19 tests. Developers 
may use alternative approaches. Developers who are considering alternative approaches should 
consider seeking FDAs feedback.
FDA can provide validation recommendations specific to a test developers situation both for 
those seeking EUA and for those seeking marketing authorization through traditional review 
pathways. Developers can send simple inquiries to CDRH-EUA-Templates@fda.hhs.gov or 
submit a pre-EUA or pre-submission for more complex inquiries.28 For tests seeking marketing 
authorization through traditional premarket review pathways, FDA may recommend validation 
studies or supportive evidence in addition to the recommendations in the EUA templates.  
Members of the public can submit questions about the templates to CDRH-EUA-
Templates@FDA.HHS.GOV, or they can submit comments regarding the templates to the public 
docket established for this guidance.
26 The FDA is working with the NIH, the Centers for Disease Control and Prevention (CDC), and BARDA to assess 
the performance of certain commercial manufacturers serology tests. As part of this project, the FDA, working with 
partnering agencies, has designed a performance assessment protocol that offers a mechanism for an independent 
evaluation of certain lateral flow and certain enzyme-linked immunosorbent assay (ELISA) or similar technology-
based SARS-CoV-2 antibody tests in a laboratory environment. Under this protocol, each test evaluated at the 
NIH/NCI will be evaluated with a well-characterized sample panel consisting of positive and negative plasma and/or 
serum samples. The approach represents a balanced attempt to provide a reasonable understanding of the potential 
performance of a significant number of the tests within a short time period. Performance results are considered 
during FDAs review of an EUA request for the test.
27 See https://www.fda.gov/medical-devices/coronavirus-disease-2019-covid-19-emergency-use-authorizations-
medical-devices/in-vitro-diagnostics-euas.
28 See FDA Guidance document Requests for Feedback and Meetings for Medical Device Submissions: The Q-
Submission Program, available at: https://www.fda.gov/regulatory-information/search-fda-guidance-
documents/requests-feedback-and-meetings-medical-device-submissions-q-submission-program. 
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