Aldeyra Therapeutics Announces Third Quarter 2017 Financial Results

Aldeyra Therapeutics Announces Third Quarter 2017 Financial Results

LEXINGTON, Mass., November 9, 2017 /PRNewswire/ Aldeyra Therapeutics, Inc. (NASDAQ: ALDX)

( Aldeyra or the Company ), a clinical-stage biotechnology company devoted to treating inflammation, inborn errors of metabolism, and other diseases related to endogenous aldehyde toxicity, today announced financial results for

the quarter ended September 30, 2017.

The announcement of clinical results in dry eye disease in the third quarter marks the fifth positive

Phase 2 clinical trial of our lead aldehyde trap, reproxalap, formerly known as ADX-102, commented Todd C. Brady, M.D., Ph.D., President and CEO of Aldeyra. Given the consistent clinical activity

of reproxalap across large-market and orphan diseases, we now look to expand our pipeline with new molecules in new indications, and, last quarter, we were pleased to announce development of ADX-103 for

Third Quarter Highlights:

Expected Clinical Milestones:

Third Quarter 2017 Financial Results

quarter, Aldeyra reported a net loss of approximately $5.0 million, compared to a net loss of approximately $4.8 million for the quarter ended September 30, 2016. Basic and diluted net loss per share was $0.32 for the quarter ended

September 30, 2017, compared to basic and diluted net loss of $0.38 per share for the quarter ended September 30, 2016. Losses have resulted from the costs of Aldeyra s clinical trials and research and development programs, as well as

from general and administrative expenses.

Research and development expenses were $3.5 million for the three months ended September 30, 2017,

compared to $3.4 million for the three months ended September 30, 2016. The increase of $0.1 million is primarily related to the increases in external research and development expenditures, including clinical, preclinical, and

manufacturing expenses.

General and administrative expenses were $1.5 million for the three months ended September 30, 2017, compared to

$1.4 million for the three months ended September 30, 2016.

Cash, cash equivalents, and marketable securities were $47.9 million as of

September 30, 2017, including $26.9 million in net proceeds from the underwritten public offering of common stock that closed on September 21, 2017.

Conference Call & Webcast Information

Aldeyra will hold a conference call on Thursday, November 9, 2017, at 8:00 a.m. eastern time to discuss the results. The

dial-in numbers are 1-877-266-8979 for domestic callers and 1-412-317-5231 for international callers. A live webcast of the conference call will also be available on the investor relations page

of the Aldeyra Therapeutics corporate website at www.aldeyra.com.

After the live webcast, the event will remain archived on the Aldeyra

Therapeutics website for one year.

About Aldeyra Therapeutics

Aldeyra Therapeutics, Inc. is a biotechnology company devoted to improving lives by inventing, developing, and commercializing products that treat

diseases thought to be related to endogenous aldehydes, a naturally occurring class of pro-inflammatory and toxic molecules. Aldeyra s lead product candidate, reproxalap, formerly known as ADX-102, is an aldehyde trap in development as topical eye drops for the treatment of ocular inflammation. Reproxalap has now been tested in over 250 patients in Phase 2 clinical trials in dry eye disease, allergic

conjunctivitis, and noninfectious anterior uveitis. A dermatologic formulation of reproxalap is in late-stage clinical development for the treatment of ichthyosis due to Sj gren-Larsson Syndrome, an inborn error of aldehyde metabolism.

Reproxalap has not been approved for sale in the U.S. or elsewhere.

About Dry Eye Disease

Dry eye disease is a common inflammatory disease estimated to affect approximately 20 million people in the United States, and is characterized by

insufficient moisture and lubrication in the anterior surface of the eye, leading to dryness, inflammation, pain, discomfort, irritation, and in severe cases, decreased vision. Among physicians and patients, existing therapy for dry eye disease is

generally regarded as inadequate. In patients with dry eye disease, pro-inflammatory aldehyde mediators may contribute to ocular inflammation. By diminishing aldehyde levels, Aldeyra s topical ocular

aldehyde trap platform represents a novel and differentiated approach for the treatment of dry eye disease.

About Allergic Conjunctivitis

Allergic conjunctivitis is a common allergic disease that affects 20% or more of the population worldwide. The disease is thought to be mediated

in part by pro-inflammatory aldehydes, and is characterized by inflammation of the conjunctiva (a membrane covering part of the front of the eye), resulting in ocular itching, excessive tear production, lid

swelling, and redness.

About Noninfectious Anterior Uveitis

Noninfectious anterior uveitis is a rare, potentially blinding disease that may be mediated in part by pro-inflammatory

aldehydes, and is characterized by inflammation in the front of the eye, pain, impaired vision, and photophobia.

About Sj gren-Larsson

Sj gren-Larsson Syndrome is a rare inborn error of aldehyde metabolism caused by mutations in fatty acid aldehyde dehydrogenase,

leading to elevated toxic fatty aldehyde levels that are thought to contribute to ichthyosis (scaly, thickened, dry skin), neurological disorders, and retinal disease. No therapy for SLS has been approved by the U.S. Food and Drug Administration.

Safe Harbor Statement

This release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including statements regarding

Aldeyra s plans and expectations for the development of Reproxalap and ADX-103; and the potential of Reproxalap as an agent for the treatment of dry eye disease and allergic conjunctivitis and ADX-103 as an agent for the treatment of retinal disease. Aldeyra intends such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 21E of

the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward-looking statements by terms such as may, might, will, objective,

intend, should, could, can, would, expect, believe, anticipate, project, target, design, estimate,

predict, potential, aim, plan or the negative of these terms, and similar expressions intended to identify forward-looking statements. Such forward-looking statements are based upon current

expectations that involve risks, changes in circumstances, assumptions and uncertainties. Aldeyra is at an early stage of development and may not ever have any products that generate significant revenue. Important factors that could cause actual

results to differ materially from those reflected in Aldeyra s forward-looking statements include, among others, the timing of enrollment, commencement and completion of Aldeyra s clinical trials, the timing and success of preclinical

studies and clinical trials conducted by Aldeyra and its development partners; updated or refined data based on Aldeyra s continuing review and quality control analysis of clinical data, Aldeyra s ability to design clinical trials with

protocols and endpoints acceptable to applicable regulatory authorities, the ability to obtain and maintain regulatory approval to conduct clinical trials and to commercialize Aldeyra s product candidates, and the labeling for any approved

products; the scope, progress, expansion, and costs of developing and commercializing Aldeyra s product candidates; the size and growth of the potential markets for Aldeyra s product candidates and the ability to serve those markets;

Aldeyra s expectations regarding Aldeyra s expenses and revenue, the sufficiency of Aldeyra s cash resources and needs for additional financing; the rate and degree of market acceptance of any of Aldeyra s product candidates;

Aldeyra s expectations regarding competition; Aldeyra s anticipated growth strategies; Aldeyra s ability to attract or retain key personnel; Aldeyra s ability to establish and maintain development partnerships; Aldeyra s

expectations regarding federal, state and foreign regulatory requirements; regulatory developments in the United States and foreign countries; Aldeyra s ability to obtain and maintain intellectual property protection for its product

candidates; the anticipated trends and challenges in Aldeyra s business and the market in which it operates; and other factors that are described in the Risk Factors and Management s Discussion and Analysis of Financial

Condition and Results of Operations sections of Aldeyra s Annual Report on Form 10-K for the year ended December 31, 2016 and Quarterly Report on Form

10-Q for the quarter ended June 30, 2017, which are on file with the Securities and Exchange Commission(SEC) and available on the SEC s website at www.sec.gov. Additional factors

may be described in those sections of Aldeyra s Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, to be filed with the SEC in the fourth quarter of 2017. All of Aldeyra s

development timelines may be subject to adjustment depending on recruitment rate, regulatory review, preclinical and clinical results, and other factors that could delay the initiation or completion of clinical trials.

In addition to the risks described above and in Aldeyra s other filings with the SEC, other unknown or unpredictable factors also could affect

Aldeyra s results. No forward-looking statements can be guaranteed and actual results may differ materially from such statements. The information in this release is provided only as of the date of this release, and Aldeyra undertakes no

update any forward-looking statements contained in this release on account of new information, future events, or otherwise, except as

Aldeyra Therapeutics, Inc.

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MacDougall Biomedical Communications

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