(EDIT) greement with Cystic Fibrosis Foundation Therapeutics

Editas to Receive up to $5 Million Award to Fund Genome Editing Research

CAMBRIDGE, Mass., May 16, 2016  — Editas Medicine, Inc. (NASDAQ:EDIT), a leading genome editing company, today announced a three-year agreement with Cystic Fibrosis Foundation Therapeutics, Inc. (CFFT), the nonprofit affiliate of the Cystic Fibrosis Foundation, in which CFFT will pay up to $5 million to Editas Medicine to support the discovery and development of CRISPR/Cas9-based medicines for the treatment of cystic fibrosis (CF). In addition, Editas will access CFFT’s extensive network of CF scientific advisors and clinical researchers.

“We are delighted to work with Cystic Fibrosis Foundation Therapeutics to discover and develop medicines for people with cystic fibrosis,” said Katrine Bosley, President and Chief Executive Officer, Editas Medicine. “While significant medical and scientific progress has been made in recent years, a great deal of work remains. I’m hopeful that our genome editing approach will one day create important new therapies that can address the genetic mutations that cause this disease.”

“We believe that the CRISPR approach to gene editing holds significant promise for repairing the underlying cause of cystic fibrosis,” said Preston W. Campbell III, M.D., President and Chief Executive Officer, CF Foundation. “We’re pleased to work with Editas Medicine and are excited by the possibilities of what can be accomplished on behalf of people with CF.”

The gene that causes CF encodes the cystic fibrosis transmembrane conductance regulator protein (CFTR), which helps maintain the water balance within the lung and in other tissues.  Mutations in this gene lead to problems with the flow of fluids and salt into and out of cells.  This causes a thick buildup of mucus in the lungs, pancreas and other organs. The mucus clogs the airways and traps bacteria, leading to chronic infections and inflammation of the airways. There are more than 1,800 known mutations within the CFTR gene. As part of this agreement, Editas Medicine will explore targeting both common mutations as well as mutations not addressed by conventional approaches.

About Editas Medicine
Editas Medicine is a leading genome editing company dedicated to treating patients with genetically defined diseases by correcting their disease-causing genes. The Company was founded by world leaders in genome editing, and its mission is to translate the promise of genome editing science into a broad class of transformative genomic medicines to benefit the greatest number of patients.

Forward-Looking Statements
This press release contains forward-looking statements and information within the meaning of The Private Securities Litigation Reform Act of 1995. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “target,” “should,” “would,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.  The Company may not actually achieve the plans, intentions, or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements.  Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various factors, including:  uncertainties inherent in the initiation and completion of preclinical studies and clinical trials and clinical development of the Company’s product candidates; availability and timing of results from preclinical studies and clinical trials; whether interim results from a clinical trial will be predictive of the final results of the trial or the results of future trials; expectations for regulatory approvals to conduct trials or to market products and availability of funding sufficient for the Company’s foreseeable and unforeseeable operating expenses and capital expenditure requirements.  These and other risks are described in greater detail under the caption “Risk Factors” included in the Company’s Annual Report on Form 10-K, which is on file with the Securities and Exchange Commission, and in other filings that the Company may make with the Securities and Exchange Commission in the future.  Any forward-looking statements contained in this press release speak only as of the date hereof, and the Company expressly disclaims any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise.

Media Contact 
Dan Budwick

Pure Communications, Inc.

(973) 271-6085 
dan@purecommunicationsinc.com

Investor Contact
Jesse Baumgartner
Stern Investor Relations, Inc.
(212) 362-1200
jesse@sternir.com