UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.     )

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☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material under §240.14a-12

Avidity Biosciences, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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  P.O. BOX 8016, CARY, NC 27512-9903 Avidity Biosciences, Inc. Important Notice Regarding the Availability of Proxy Materials   Stockholders Meeting to be held on June 16, 2021 For stockholders as of record on April 19, 2021   This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. This is not a ballot. You cannot use this notice to vote your shares. We encourage you to access and review all of the important information contained in the proxy materials before voting.   To view the proxy materials, and to obtain directions to attend meeting, go to: www.proxydocs.com/RNA   To vote your proxy while visiting this site, you will need the 12 digit control number in the box below.   Under United States Securities and Exchange Commission rules, proxy materials do not have to be delivered in paper. Proxy materials can be distributed by making them available on the internet.  

	For a convenient way to view proxy materials and VOTE go to www.proxydocs.com/RNA Have the 12 digit control number located in the shaded box above available when you access the website and follow the instructions.
	If you want to receive a paper or e-mail copy of the proxy material, you must request one. There is no charge to you for requesting a copy. In order to receive a paper package in time for this year’s meeting, you must make this request on or before June 04, 2021. To order paper materials, use one of the following methods.

INTERNET www.investorelections.com/RNA	TOLL-FREE TELEPHONE (866) 648-8133	* E-MAIL paper@investorelections.com

When requesting via the Internet or telephone you will need the 12 digit control number located in the shaded box above. * If requesting material by e-mail, please send a blank e-mail with the 12 digit control number (located above) in the subject line. No other requests, instructions OR other inquiries should be included with your e-mail requesting material.

Avidity Biosciences, Inc.

Meeting Type: Annual Meeting of Stockholders
Date: Wednesday, June 16, 2021
Time: 09:00 AM, Pacific Time
Place: Annual Meeting to be held live via the Internet. Please visit
            www.proxydocs.com/RNA for more details.

You must register to attend the meeting online and/or participate at www.proxydocs.com/RNA

SEE REVERSE FOR FULL AGENDA

Avidity Biosciences, Inc.

Annual Meeting of Stockholders

THE BOARD OF DIRECTORS RECOMMENDS A VOTE

“FOR” ON PROPOSALS 1 AND 2

PROPOSAL

1. To elect three Class I directors for a three-year term that expires at the 2024 Annual Meeting of Stockholders and until their respective successors shall have been duly elected and qualified

1.01 Carsten Boess

1.02 Sarah Boyce

1.03 Troy Wilson, Ph.D., J.D.

2. To ratify the appointment of BDO USA, LLP as our independent public accounting firm for the fiscal year ending December 31, 2021.

3 To transact such other business as may properly come before the Annual Meeting or any continuation, postponement, or adjournment of the Annual Meeting.