Form of Exchange Agreement

Exhibit 10.21

Viveon Health Acquisition Corp.

As of May 1, 2023

Reference is made to the following documents:

As you know, on April 5, 2023, Viveon has entered into a Business Combination Agreement to acquire Clearday. In connection with the merger contemplated by such agreement (the “Merger”) and as set forth in the Termsheet, Clearday is conducting an offering (the “Clearday Bridge”) of securities in advance of the Merger of up to $16 million of Clearday Notes, including $4 million of Clearday Notes issuable to holders of Extension Notes and Extension Warrants in exchange for such securities. The purpose of the Clearday Bridge is to, among other things, permit Clearday and Viveon to pay expenses relating to, and in advance of, the Merger.

Viveon respectfully requests your consent to exchange your Extension Notes and Extension Warrants for a principal amount of Clearday Notes equal to the principal amount of your Extension Notes effective immediately prior to the consummation of the Merger.

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Please indicate your consent where indicated below to exchange your Extension Notes and Extension Warrants for Clearday Notes as described herein effective immediately prior to the consummation of the Merger. By executing this consent, you confirm that your representations and warranties set forth in the Subscription agreement are true and correct as of the date hereof and as of the date of the consummation of the Merger with respect to the Clearday Notes.