DMTX Dimension Therapeutics, Inc.

Dimension Therapeutics, Inc. (NASDAQ:DMTX), a biopharmaceutical company advancing novel, adeno-associated virus (AAV) gene therapies targeting the liver, a key organ for human metabolism, today announced poster presentations that will highlight advances in mammalian vector manufacturing for the Company’s novel pipeline of product candidates. The presentations will take place during the upcoming ESGCT Congress, taking place in Florence, Italy, October 18-21, 2016.

“We are pleased that the ESCGT has chosen to highlight the innovation supporting our current and next generation HELA 2.0 AAV manufacturing platform,” said Dr. Annalisa Jenkins, MBBS, FRCP, Chief Executive Officer of Dimension. “As an early clinical-stage company, we continue to enhance our scientific platform, making important progress most recently with the addition of our non-GMP facility in Woburn, Massachusetts. We are committed every day to innovation in the science and medicine of rare diseases associated with the liver and in the delivery of a robust, sustainable quality manufacturing platform.”

The poster presentation details are as follows:

Title: Establishing a clone selection strategy to accelerate recombinant adeno-associated virus (rAAV) producer cell line development (Poster #P368)Session Title: Poster Session IISession Viewing Dates Include: Thursday, October 20, 2016Location: Palazzo degli Affari, Second Floor, Leonardo RoomAuthors: Nicholas Richards1, Alix Eastham1, Aubrey R. Tiernan1, Vincent Borowy1, K. Reed Clark1, Samuel C. Wadsworth1, Christopher Tipper1, and Ying Jing1  1Dimension Therapeutics, Inc.

Title: Molecular assay toolbox to identify characteristics of recombinant adeno-associated virus (rAAV)-producing cell lines (Poster #P379)Session Title: Poster Session ISession Viewing Dates Include: Wednesday, October 19, 2016Location: Palazzo degli Affari, Second Floor, Leonardo RoomAuthors: Aubrey R. Tiernan1, Nicholas Richards1, Alix Eastham1, Vincent Borowy1, K. Reed Clark1, Samuel C. Wadsworth1, and Christopher Tipper1  1Dimension Therapeutics, Inc.

Title: Particle titer determination and characterization of rAAV molecules using nanoparticle tracking analysis and other techniques (Poster #P394)Session Title: Poster Session IISession Viewing Dates Include: Thursday, October 20, 2016Location: Palazzo degli Affari, Second Floor, Leonardo RoomAuthors: Samantha F. Povlich1, Jonathan G. Mehtala2, William Zolla1, Samuel C. Wadsworth1, K. Reed Clark1, and Gwendolyn M. Wilmes1  1Dimension Therapeutics, Inc.; 2Malvern Instruments

About Dimension Therapeutics

Dimension Therapeutics, Inc. (NASDAQ:DMTX) is the leader in discovering and developing new therapeutic products for people living with devastating rare diseases associated with the liver, based on the most advanced, mammalian adeno-associated virus (AAV) gene delivery technology. Dimension is actively progressing its broad pipeline, which features programs addressing unmet needs for patients suffering from inherited metabolic diseases, including OTC deficiency, GSDIa, citrullinemia type 1, PKU, Wilson disease, a collaboration with Bayer in hemophilia A, and a wholly owned clinical program in hemophilia B. The company targets diseases with readily identifiable patient populations, highly predictive preclinical models, and well-described, and often clinically validated, biomarkers. Founded in 2013, Dimension maintains headquarters in Cambridge, Massachusetts.

For more information, please visit http://www.dimensiontx.com.

Cautionary Note Regarding Forward-Looking Statements

This press release contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, statements regarding the development of new manufacturing processes, the anticipated advantages of the new facility, increased production and scale capacity, and growth in Dimension's portfolio. All such forward-looking statements are based on management's current expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in or implied by such forward-looking statements. These risks and uncertainties include the risks that the benefits of new manufacturing processes will not be realized; Dimension's product candidates, including its lead candidate, DTX101, will not successfully be developed or commercialized; and the risks described under the caption "Risk Factors" in Dimension Therapeutics’ Quarterly Report on Form 10-Q for the quarter ended June 30, 2016, which is on file with the Securities and Exchange Commission, as well as other risks detailed in Dimension Therapeutics’ additional filings with the Securities and Exchange Commission. All information in this press release is as of the date of the release, and Dimension Therapeutics undertakes no duty to update this information unless required by law.

CONTACT:

Jean Franchi
Chief Financial Officer
Dimension Therapeutics
617-714-0709
jean.franchi@dimensiontx.com

Burns McClellan, on behalf of Dimension Therapeutics
Media: Justin Jackson
212-213-0006, ext.327
jjackson@burnsmc.com