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State of California—Health and Human Services Agency
California Department of Public Health

March 26, 2020

Laboratory Directors and Managers

Important Information for Laboratories about Lab Developed Tests for SARS-CoV-2/COVID-19

***Revised: December 6, 2021***

Dear Laboratory Directors and Managers,

On November 15, 2021, the Food and Drug Administration (FDA) issued a revised policy that supersedes its “Policy for Coronavirus Disease-2019 Tests During the Public Health Emergency” issued in May 2020. The revised policy includes two changes important for laboratories performing laboratory-developed tests (LDTs). The revised policy (PDF) is available on the FDA website (

State Authorization of COVID-19 Tests

On February 29, 2020, the Food and Drug Administration (FDA) issued guidance authorizing diagnostic testing for SARS-CoV-2, the virus that causes COVID-19, pursuant to the Emergency Use Authorization (EUA) process. On March 16, 2020, the FDA provided updated guidance that presented a policy granting states flexibility in authorizing laboratories with the state to develop and perform tests used to test for COVID-19. The FDA memorandum stated that a state "choosing to authorize laboratories within that State . . . to develop and perform a test for COVID-19 would do so under the authority of its own State law . . . ."

The revised guidance issued by the FDA on November 15, 2021, clarifies that the FDA no longer intends to apply to any additional States or territories the policy that would allow a State or territory to authorize laboratories within the State or territory to develop and perform a test for COVID-19 under authority of its own State law.

The California Department of Public Health (CDPH) has not established a process to independently authorize the manufacturing, use, and distribution of COVID-19 tests.

Premarket Review and Approval of LDTs for COVID-19 Tests

The revised November 2021 guidance also changes the May 2020 policy that suspended requirements for premarket review and approval of LDTs for COVID-19 tests. The new policy withdraws that suspension, and updates FDA policies for COVID-19 tests, including COVID-19 LDTs. Going forward the FDA now generally expects newly offered COVID-19 tests, including LDTs, to have an EUA, or traditional marketing authorization prior to clinical use.

For tests currently being offered without the submission of an EUA request, the FDA generally expects the submission of an EUA request as described in the guidance. If a laboratory is using an LDT that it was performing prior to the new policy announcement on November 15, the laboratory can continue to use the LDT but should submit documentation for FDA review. For such tests and tests with pending EUA requests, FDA generally intends to review the EUA requests and, if the test is not subsequently authorized, expects developers to cease marketing the test within 15 calendar days of being notified.

All California-licensed clinical laboratories must follow the revised guidance and submit an EUA request for any laboratory developed tests to the FDA as soon as possible.

For more information, please consult the revised policy (PDF), which is available on the FDA website (

CDPH requests that any clinical laboratory that has questions about the new FDA guidance contact the FDA. Contact information is available on the FDA website (

A laboratory that has chosen oversight by a California-approved accrediting organization may have questions regarding how the LDT process applies to them. In this instance, the laboratory should contact its respective accrediting organization and copy Laboratory Field Services at


Original signed by Robert J. Thomas

Robert J. Thomas

Branch Chief

     Laboratory Field Services ● 850 Marina Bay Parkway ● Richmond, CA 94804
    (510) 620-3800 ● (510) 620-3692 FAX
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