UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.     )

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☐ Preliminary Proxy Statement

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☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

ALDEYRA THERAPEUTICS, 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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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Stockholder Meeting to Be Held on June 4, 2019.

			Meeting Information
	ALDEYRA THERAPEUTICS, INC.		Meeting Type:     Annual Meeting
			For holders as of: April 8, 2019
			Date: June 4, 2019      Time: 8:00 AM EDT
			Location:	Offices of Gunderson Dettmer Stough
				Villeneuve Franklin & Hachigian, LLP
				One Marina Park Drive, Suite 900
				Boston, MA 02210
	ALDEYRA THERAPEUTICS, INC. 131 HARTWELL AVE. LEXINGTON, MA 02421	You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting.
		See the reverse side of this notice to obtain proxy materials and voting instructions.

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Voting items

The Board of Directors recommends you vote
FOR the following:
1.	Election of Three Class II Directors
	Nominees
	01) Richard H. Douglas, Ph.D.       02) Gary Phillips, M.D.       03) Neal Walker, D.O.
The Board of Directors recommends you vote FOR proposals 2 and 3.
2.	To ratify the appointment of BDO USA, LLP as Aldeyra Therapeutics, Inc.’s independent registered public accounting firm for the year ending December 31, 2019.
3.	To approve an amendment to Aldeyra Therapeutics, Inc.’s 2013 Equity Incentive Plan (2013 Plan) to remove the annual limitations on the number of shares subject to awards that may be issued to eligible service providers under the 2013 Plan.
NOTE: Such other business as may properly come before the meeting or any adjournment thereof.