Repli Gen Repligen Corporation 41 Seyon Street Building #1, Suite 100 Waltham, Massachusetts 02453 Telephone: (781) 250-0111 FOR IMMEDIATE RELEASE Telefax: (781) 250-0115 Repligen Reports Third Quarter 2014 Financial Res

Repligen Reports Third Quarter 2014 Financial Results

- Product Revenue Increases 24% to $15.2 Million -

- Product Gross Profit Increases 26% to $8.2 Million -

- Conference Call and Webcast Today at 8:30 a.m. EST -

WALTHAM, MA November 6, 2014 Repligen Corporation (NASDAQ:RGEN) today reported financial results for its third quarter ended

September 30, 2014. The Company s financial and business highlights for the third quarter and year-to-date follow, as well as updated financial guidance for the year 2014.

Third Quarter Financial Highlights:

Repligen Reports Third Quarter 2014 Financial Results

Repligen reported strong revenue growth for the third quarter based on increased demand for Protein A affinity ligands and our OPUS line of pre-packed chromatography columns, said Walter C. Herlihy, Ph.D., President and CEO of Repligen. We are encouraged by the rapid uptake of OPUS 45, our largest diameter column

which we launched in March, and by the adoption of our OPUS line by several key customers at multiple manufacturing sites.

Operating expenses for

the three-month period ended September 30, 2014 were $13.1 million compared to $10.8 million for the same period in 2013, an increase of $2.3 million or 21%. This increase was primarily driven by increased cost of goods associated with higher

product sales and higher selling, general and administrative (SG&A) expenses, partially offset by the absence of cost of royalty. During the third quarter of 2014, SG&A increased by $1.6 million compared with the same period during 2013.

This increase included approximately $339,000 of transaction expenses associated with our June 2, 2014 acquisition of the business of Refine Technology and increased expenses related to the expansion of our facilities and our commercial

organization. Research and development expense increased by $220,000 or 15% during the third quarter of 2014 compared with same period in 2013, primarily due to our increased investment in new product development during the 2014 period. Earnings per

diluted share were $0.04 for the third quarter of 2014 compared to $0.18 for the same period in 2013.

Year-to-Date Financial Summary:

Product revenue for the nine-month period ended September 30, 2014 was $45.0 million compared to $37.1 million for the same period in 2013, an increase of

21%. Product gross profit was $25.1 million or 55.7% of product revenue for the nine-month period ended September 30, 2014, compared to $19.3 million or 51.9% of revenue during the same period in 2013, an increase of 30%. Total revenue for the

nine-month period ended September 30, 2014 was $47.2 million compared to $52.8 million for the same period in 2013, a decrease of 11%. During the 2013 period, total revenue included $15.7 million of royalty and other revenue, compared with $2.1

million during the 2014 period. Operating expenses for the nine-month period of 2014 were $36.5 million, including approximately $816,000 in one-time expenses associated with the Refine acquisition, compared to $35.1 million for the 2013 period, an

increase of 4%. Operating income for the nine-month period ended September 30, 2014 was $10.6 million compared to $17.7 million for the same period in 2013. Net income for the nine-month period ended September 30, 2014 was $8.6 million

compared to $12.8 million for the same period in 2013. Earnings per diluted share for the nine-month period ended September 30, 2014 were $0.26 compared to $0.40 for the 2013 period.

Financial Guidance for 2014

Today we are revising our

financial guidance for the year 2014 based on expectations for our existing business, excluding the impact on our revenue and expenses of: potential milestone payments from therapeutic out-licenses; additional potential acquisitions; and future

fluctuations in foreign currency exchange rates.

Repligen Reports Third Quarter 2014 Financial Results

Adjustments to our previous guidance:

Consistent with our previous guidance:

Recent Business Updates

Repligen will host a conference call and

webcast today, November 6, at 8:30 a.m. EST, to discuss third quarter 2014 financial results and business updates. The live call can be accessed by dialing toll-free 844-835-7432 for domestic callers or 404-537-3372 for international callers.

Dial-in participants must provide the passcode 24804552. In addition, a webcast will be accessible via the Investor Relations section of Repligen s website www.repligen.com; see Events & Presentations. Both the conference call and

webcast will be archived for a period of time following the live event. The replay dial-in numbers are 855-859-2056 for domestic callers and 404-537-3406 for international callers. Replay listeners must provide the passcode 24804552.

Repligen Reports Third Quarter 2014 Financial Results

About Repligen Corporation

Repligen Corporation

(NASDAQ:RGEN) is a life sciences company focused on the development and commercialization of high-value consumable products used in the process of manufacturing biological drugs. Our bioprocessing products are sold to major life sciences and

biopharmaceutical companies worldwide. We are the leading manufacturer of Protein A affinity ligands, a critical component of Protein A media that is used to separate and purify monoclonal antibody therapeutics. Our ATF (Alternating Tangential Flow)

System and our growth factor products are used to increase product yield during the fermentation stage of biologic drug manufacturing. In addition, we developed and market an innovative line of ready-to-use chromatography columns under

our OPUS brand that we deliver pre-packed with our customers choice of purification media. Repligen s corporate headquarters are in Waltham, MA (USA) and our manufacturing

facilities are located in Waltham, MA and Lund, Sweden.

This press release contains forward-looking statements, which are made pursuant to the safe

harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Investors are cautioned that statements in this press release which are not strictly historical

statements, constitute forward-looking statements, including, without limitation, express or implied statements or guidance regarding future financial performance and position, including cash and investment position, our strategic decision to focus

on the growth of our bioprocessing business, the future demand for our bioprocessing, growth factor, ATF and chromatography products, plans and objectives for future operations, our expectations related to the transition of our ATF System operations

from New Jersey to our headquarters, plans and objectives for product development and acquisitions, our market share and product sales and other statements identified by words like believe, expect, may,

will, should, seek, anticipate, or could and similar expressions. Such forward-looking statements are subject to a number of risks and uncertainties that could cause actual results to

differ materially from those anticipated, including, without limitation, risks associated with: our ability to successfully grow our bioprocessing business, including as a result of acquisition, commercialization or partnership opportunities; our

ability to successfully integrate and realize the expected benefit from the acquisition of the business of Refine Technology; our ability to develop and commercialize products and the market acceptance of our products; reduced demand for our

products that adversely impacts our future revenues, cash flows, results of operations and financial condition; the impact of the expiration on December 31, 2013 of Bristol-Myers Squibb royalty payments from U.S. sales of Orencia , the success of current and future collaborative or supply relationships, including our agreement with Pfizer and our agreement with BioMarin; our ability to compete with larger, better financed

bioprocessing, pharmaceutical and biotechnology companies; our compliance with all Food and Drug Administration and EMEA regulations; our ability to obtain, maintain and protect intellectual property rights for our products; the risk of litigation

regarding our intellectual property rights; our limited sales capabilities; our volatile stock price; and other risks detailed in Repligen s Annual Report on Form 10-K on file with the Securities and Exchange Commission and the other reports

that Repligen periodically files with the Securities and Exchange Commission. Actual results may differ materially from those Repligen contemplated by these forward-looking statements. These forward looking statements reflect management s

current views and Repligen does not undertake to update any of these forward-looking statements to reflect a change in its views or events or circumstances that occur after the date hereof except as required by law.

Director Investor Relations

Repligen Corporation

Repligen Reports Third Quarter 2014 Financial Results

REPLIGEN CORPORATION

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