Eloxx Pharmaceuticals Reports First Quarter 2018 Financial and Operating Results and Provides Business Update Company on track to initiate Phase 2 clinical trials for investigational drug ELX-02 in cystic fibrosis and cy

Eloxx Pharmaceuticals Reports First Quarter 2018 Financial and Operating Results and Provides Business

Company on track to initiate Phase 2 clinical trials for investigational drug ELX-02

in cystic fibrosis and cystinosis in 2018 and sufficiently funded to top line data

Formation of Scientific Advisory Board with

expertise in nonsense mutations and nonsense mediated decay

Company to host webcast and conference call on Thursday, May 10,

Waltham, MA. May 10, 2018 Eloxx Pharmaceuticals, Inc. ( Eloxx ),

(ELOX, NASDAQ) a clinical-stage biopharmaceutical company dedicated to the discovery and development of novel therapeutics to treat cystic fibrosis, cystinosis and other diseases caused by nonsense mutations limiting production of functional

proteins, today reported its financial results for the three months ended March 31, 2018, and provided a business update.

Recent Accomplishments

We are pleased to have successfully raised $53.4 million in a public offering in April and to be trading on the Nasdaq. We are on

track to seek regulatory clearance to initiate Phase 2 clinical trials for our lead investigational product candidate, ELX-02, in cystic fibrosis and cystinosis this year, and are funded through to top line

data readouts, said Robert E. Ward, Chairman and CEO of Eloxx Pharmaceuticals. We look forward to sharing additional scientific data for ELX-02 with the scientific community at the European Cystic

Fibrosis Society Meeting in Belgrade, Serbia June 5-9, 2018. We are also extremely gratified to have attracted high caliber experts to our inaugural Scientific Advisory Board and expect that they will provide

us with wise counsel as we advance our library of product candidates designed to be eukaryotic ribosomal selective glycosides.

Investigational Drug ELX-02 in Cystic Fibrosis and Cystinosis

We are currently developing our lead

investigational drug, ELX-02, for the treatment of cystic fibrosis and cystinosis patients with diagnosed nonsense mutations. We have held pre-clinical trial application

(CTA) discussions with the Federal Agency for Medicines and Health Products (FAMHP) in Brussels,

Belgium and pre-IND discussions with the U.S. Food & Drug Administration (FDA) for cystic fibrosis and cystinosis, respectively.

Currently, the European Medicines Agency (EMA) has designated ELX-02 as an orphan medicine for the treatment of

mucopolysaccharidosis type I (MPS I), and the FDA has granted orphan drug designation to ELX-02 for the treatment of cystinosis, MPS I and for the treatment of Rett Syndrome.

41st European Cystic Fibrosis Conference (ECFS)

Eloxx will present two abstracts at ECFS in Belgrade, Serbia, June 6-9, 2018, including one Later-Breaker, for our lead

investigational candidate, ELX-02. The details of these presentations are as follows:

Presenter: Neal Sharpe, Ph.D., Vice President, Translational

Sciences, R & D, Eloxx Pharmaceuticals

Time: Thursday, June 7, 2018 from 3:30 pm - 3:45 pm CET, or 9:30 am - 9:45 am

Presenter: Dr. Pedro Huertas, Chief Medical Officer, Eloxx Pharmaceuticals

Time: Friday, June 8, 2018 from 5:00 pm - 5:30 pm CET, or 11:00 am - 11:30 pm ET

Scientific Advisory Board

Eloxx announced today the

formation of its inaugural Scientific Advisory Board (SAB) and the appointment of the following world leading experts:

Eloxx today also announced that it has entered into a technology evaluation agreement with Ionis Pharmaceuticals,

Inc. to explore potential therapeutic applications of antisense technology and eukaryotic ribosomal selective glycosides for use in rare or ultrarare genetic disorders.

First Quarter 2018 Financial Results

March 31, 2018, we had cash and cash equivalents of $18.3 million, On April 30, 2018, we closed on an underwritten public offering raising an estimated $53.4 million, net of fees. We expect that our current cash and cash

equivalents will be sufficient to fund our current operations to 2020 and through data readouts for our Phase 2 clinical trials for our investigation product, ELX-02, in cystic fibrosis and cystinosis.

We incurred a loss for the three months ended March 31, 2018, of $8.6 million or 0.31 per share, which includes

one-time charges of $2.1 million in working capital, and $0.7 million non-cash expenses related to stock-based compensation. The Company incurred a net loss

for the three months ended March 31, 2017, of $2.7 million, or $0.73 per share. For the three months ended March 31, 2018, the net cash used in operating activities was $5.8 million. For the three months ended March 31,

2017, the net cash used in operating activities was $2.7 million driven primarily by our net loss.

Our research and development expenses were

$4.0 million for the three months ended March 31, 2018, compared to $2.4 million for the three month period ended March 31, 2017, an increase of $1.6 million due to increased fees and salaries and growth in clinical

Our general and administrative expenses were approximately $2.5 million for the three months ended March 31, 2018 compared to

approximately $0.3 million for the three months ended March 31, 2017, an increase of approximately $2.2 million. The increase in our general and administrative expenses was primarily related to an increase in our headcount and related

salaries, non-cash stock-based compensation, as well as other personnel and facility related costs.

Date: Thursday, May 10, 2018

Domestic Dial-in Number: (866) 913-8546

International Dial-in Number: (210) 874-7715

Conference ID: 7858608

Live Webcast: accessible from the Company s website at www.eloxxpharma.com under Events and Presentations or with this link:

https://edge.media-server.com/m6/p/n7s8dtq6. A replay will be available on the Company s website approximately two hours after the call.

Conference Call Replay Information:

Domestic Dial-in Number: (855) 859-2056

International Dial-in Number: (404) 537-3406

Conference ID: 7858608

About Eloxx Pharmaceuticals

Eloxx Pharmaceuticals, Inc. is a clinical-stage biopharmaceutical company developing novel RNA-modulating drug

candidates (designed to be eukaryotic ribosomal selective glycosides) that are designed to treat rare and ultra-rare premature stop codon diseases. Premature stop codons are point mutations that disrupt protein synthesis from messenger RNA. As a

consequence, patients with premature stop codon diseases have reduced or eliminated protein production from the mutation bearing allele accounting for some of the most severe phenotypes in these genetic diseases. These premature stop codons have

been identified in over 1,800 rare and ultra-rare diseases. Read-through therapeutic development is focused on extending mRNA half-life and increasing protein synthesis by enabling the cytoplasmic ribosome to read through premature stop codons

to produce full-length proteins. Eloxx s lead product candidate, ELX-02, is a small molecule drug candidate designed to restore production of full-length functional proteins. Eloxx s preclinical

candidate pool consists of a library of novel drug candidates designed to be eukaryotic ribosomal selective glycosides identified based on read-through potential. ELX-02 is in the early stages of clinical

development focusing on cystic fibrosis and cystinosis. ELX-02 is an investigational drug that has not been approved by any global regulatory body. Eloxx is headquartered in Waltham, MA, with R&D

operations in Rehovot, Israel.

Forward-Looking Statements

Certain statements included in this press release are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and

involve a number of risks and uncertainties. These statements may be identified by introductory words such as may, expects, plan, believe, will, achieve, anticipate,

would, should, subject to or words of similar meaning, or by the fact that they do not relate strictly to historical or current facts. These include statements of management s intentions, beliefs, plans

and future expectations and, therefore, you are cautioned not to place undue reliance on them. Such forward-looking statements involve risks and uncertainties and actual results could differ materially from any forward-looking statements expressed

or implied herein. The risks and uncertainties that could result in actual results to differ materially from these forward-looking statements expressed or implied herein include, but are not limited to: the development of the Company s

read-through technology; the approval of the Company s patent applications; the Company s ability to successfully defend its intellectual property or obtain the necessary licenses at a cost acceptable to the Company, if at all; the

successful implementation of the Company s research and development programs and collaborations; the success of the Company s license agreements; the Company s ability to obtain applicable regulatory approvals for its current and

future product candidates; the acceptance by the market of the Company s products should they receive regulatory approval; the timing and success of the Company s preliminary studies, preclinical research, clinical trials, and related

regulatory filings; the ability of the Company to consummate additional financings as needed; the ability of the Company to manage the transition to being listed on The Nasdaq Global Market; the ability of the Company to work with its Scientific

Advisory Board; as well as other factors expressed from time to time in the Company s periodic filings with the Securities and Exchange Commission (the SEC ). As a result, this press release should be read in conjunction with the

Company s 10-K, 10-Qs and other filings with the SEC. The forward-looking statements contained herein are made only as of the date of this press release, and the

Company undertakes no obligation to publicly update or revise such forward-looking statements to reflect subsequent events or circumstances.

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