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  5. Cue Health, Inc. - 675673 - 05/09/2024
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Cue Health, Inc. MARCS-CMS 675673 —

Delivery Method:
Medical Devices

Recipient Name
Mr. Clint Sever
Recipient Title
Chief Executive Officer
Cue Health, Inc.

4980 Carroll Canyon Rd Ste 100
San Diego, CA 92121-1736
United States

Issuing Office:
Center for Devices and Radiological Health

United States

CMS# 675673

May 9, 2024

Dear Mr. Sever:

The Food and Drug Administration (FDA) conducted an inspection of your firm’s medical device operations at Cue Health, Inc. (“Cue Health”, “you”, or “your firm”) located at 4980 Carroll Canyon Rd Ste 100, San Diego, CA 92121-1736 on 10 dates between October 17, 2023 and November 3, 2023. During this inspection, the investigator determined that your firm markets and distributes the Cue Health COVID-19 Test and the Cue Health COVID-19 Test for Home and Over The Counter (OTC) Use. Under section 201(h) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 321(h), these products are devices because they are intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body.

FDA authorized the Cue Health COVID-19 Test under EUA200248 on June 10, 2020, granted revisions to the authorized labeling on August 20, 2020, and subsequently re-issued the emergency use authorization (EUA) in its entirety on March 26, 2021. The COVID-19 Test is authorized for the qualitative detection of nucleic acid from SARS-CoV-2 in direct anterior nasal swabs or in previously collected anterior nasal specimens in viral transport media from individuals with or without symptoms or other epidemiological reasons to suspect COVID-19. Emergency use of this test is limited to authorized laboratories.

FDA also authorized the Cue Health COVID-19 Test for Home and Over The Counter (OTC) Use under EUA210180 on March 5, 2021. The COVID-19 Test for Home and Over The Counter (OTC) Use is a molecular diagnostic test for the qualitative detection of nucleic acid from SARS-CoV-2 in anterior nasal (nasal) swab specimens collected with the Cue Sample Wand. The test is intended for use in adults (self-swabbing) or children ≥2 years of age (swabbed by an adult) with or without symptoms or other epidemiological reasons to suspect COVID-19 and is authorized for non-prescription home use.

Our inspection revealed that you are not complying with the following Conditions of Authorization in the Letters of Authorization for EUA200248 and EUA210180. For example:

1. Evidence obtained during the inspection demonstrated that your firm implemented several changes to your EUA-authorized devices and implemented those changes without authorization from FDA pursuant to the Conditions of Authorization. For example, documentation showed that on October 23, 2023, your firm implemented change order CP-4166 to both EUA-authorized COVID-19 devices. As part of this change order, it appears that you implemented changes in the formulation of your (b)(4), which serves as a substrate for the reaction and is responsible for generating the signal to detect the presence of the target, modified the (b)(4) and updated the device firmware to add functionality to detect failure of (b)(4), and added a (b)(4) to modify the raw electrochemical signal from the reaction to correct for observed temperature-based signal differences, and that these changes were implemented after your firm received an EUA-authorization for your devices and in the absence of notification or FDA concurrence. These modifications may negatively impact the stability of the devices, resulting in failure earlier than the 9 months claimed on the product labeling, as documents TS0496 and TS0555 observed during our inspection indicated that these modifications were implemented with the intent to affect overall device performance and in particular device stability.

Pursuant to Condition K (EUA200248) and Condition L (EUA210180), “You may request changes to this EUA for your product, including to the Scope of Authorization (Section II in this letter) or to the authorized labeling, including requests to make available additional authorized labeling specific to an authorized distributor. Such additional labeling may use another name for the product but otherwise must be consistent with the authorized labeling and shall not exceed the terms of authorization of this letter. Any request for changes to this EUA should be submitted to the Division of Microbiology (DMD)/Office of Health Technology 7 (OHT7)-Office of In Vitro Diagnostics and Radiological Health (OIR)/Office of Product Evaluation and Quality (OPEQ)/Center for Devices and Radiological Health (CDRH) and require appropriate authorization from FDA prior to implementation”. CDRH has reviewed the information collected during the inspection and has determined that your firm has failed to submit a request for the changes identified above to your devices for FDA review and obtain FDA authorization prior to implementation. CDRH has determined that these are significant modifications, as they have a strong likelihood to impact the performance of the device due to significant changes to reagent formulations and device design of these devices. Therefore, you are not permitted to distribute the modified Cue Health COVID-19 Test or Cue Health COVID-19 Test for Home and Over The Counter (OTC) Use until you receive authorization.1 We request that you take immediate action to cease the sale and distribution of your Cue Health COVID-19 Test and your Cue Health COVID-19 Test for Home and Over The Counter (OTC) Use until such time that you have received FDA concurrence for the modifications you have made to your tests pursuant to your respective conditions of authorization.

2. Pursuant to Condition M (EUA200248) and Condition N (EUA210180), your firm is required to have lot release activities to ensure that the product released meets the clinical and analytical performance claimed in the authorized labeling. CDRH has reviewed the information collected during the inspection and has determined that you are not in compliance with Conditions M and N of the respective EUAs. For example, inspection of your firm’s document “QC2900005 Cartridge Assembly, COVID-19, Pouched” (Revision 12) effective since August 31, 2022, has identified that your firm is using an Acceptable Quality Level (AQL) for functional testing of the COVID-19 cartridges when testing against negative panels which would allow for a failure rate for commercially released product to be higher than the stated Negative Percent Agreement (NPA) clinical performance claims for the EUA devices. Your EUA-authorized devices have a claimed performance of 99.1% Negative Percent Agreement (NPA). However, your lot release activities indicate that you are using an AQL of (b)(4)% which is not sufficient to ensure that tests released for distribution have the analytical and clinical performance claimed in the authorized labeling. The release of products that fail to meet their claimed performance could lead to an increase in false positive results.

Your firm should take prompt action to address any violations identified in this letter. Failure to adequately address this matter may result in regulatory action being initiated by the FDA without further notice. These actions include, but are not limited to, seizure, injunction, and civil money penalties.

Other federal agencies may take your compliance with the FD&C Act and its implementing regulations into account when considering the award of federal contracts. Additionally, should FDA determine that you have Quality System regulation violations that are reasonably related to premarket approval applications for Class III devices, such devices will not be approved until the violations have been addressed. Should FDA determine that your devices or facilities do not meet the requirements of the Act, requests for Certificates to Foreign Governments (CFG) may not be granted.

Please notify this office in writing within fifteen business days from the date you receive this letter of the specific steps your firm has taken to address the noted violations, as well as an explanation of how your firm plans to prevent these violations, or similar violations, from occurring again. Include documentation of the corrections and/or corrective actions (which must address systemic problems) that your firm has taken. If your firm’s planned corrections and/or corrective actions will occur over time, please include a timetable for implementation of those activities. If corrections and/or corrective actions cannot be completed within fifteen business days, state the reason for the delay and the time within which these activities will be completed.

Your firm’s response should be comprehensive and address any violations included in this Warning Letter. If you believe that your products are not in violation of the FD&C Act, include your reasoning and any supporting information for our consideration as part of your response.

Your firm’s response should be sent to: Jessica Mu, Director of Compliance Branch, at ORADevices3FirmResponse@fda.hhs.gov and CDRHWarningLetterResponse@fda.hhs.gov. Refer to CMS #675673 when replying. If you have any questions about the contents of this letter, please contact: Shaquenta Y. Perkins, Compliance Officer, at (619) 941-3763 or shaquenta.perkins@fda.hhs.gov.

Finally, you should know that this letter is not intended to be an all-inclusive list of the violations at your firm’s facility. It is your firm’s responsibility to ensure compliance with applicable laws and regulations administered by FDA. The specific violations noted in this letter and in the Inspectional Observations, FDA 483, issued at the close of the inspection may be symptomatic of serious problems in your firm’s manufacturing and quality management systems. Your firm should investigate and determine the causes of any violations and take prompt actions to address any violations and bring the products into compliance.

Sincerely yours,
Shari J. Shambaugh
Program Division Director
Office of Medical Device and Radiological Health
Operations Division 3
Office of Regulatory Affairs


Courtney Lias
Acting Director
OHT 7: Office of In Vitro Diagnostics
Office of Product Evaluation and Quality
Center for Devices and Radiological Health


1 We note that a device is adulterated under section 501(f)(1)(B) of the Act, 21 U.S.C. § 351(f)(1)(B), if it does not have an approved application for premarket approval (PMA) in effect pursuant to section 515(a) of the Act, 21 U.S.C. § 360e(a), or an approved application for an investigational device exemption under section 520(g) of the Act, 21 U.S.C. § 360j(g). A device is also misbranded under section 502(o) the Act, 21 U.S.C. § 352(o), if a firm does not notify the agency of its intent to introduce the device into commercial distribution, as required by section 510(k) of the Act, 21 U.S.C. § 360(k), and 21 CFR 807.81(a)(3)(i). For a device requiring premarket approval, the notification required by section 510(k) is deemed satisfied when a PMA is pending before the FDA [21 CFR 807.81(b)].

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