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 Second Quarter 2014 Financial Results - Pr

Repligen Reports Second Quarter 2014 Financial Results

- Product Revenue Increases 19.5% to a Record $15.6 Million -

- Product Gross Profit Increases 15.1% to a Record $8.9 Million -

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

WALTHAM, MA August 11, 2014 Repligen Corporation (NASDAQ:RGEN) today reported financial results for its second quarter ended

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

Second Quarter Financial Highlights:

The Company s second quarter was

highlighted by record product sales, our strategic acquisition of the bioprocessing business of Refine Technology and by several key management appointments including Tony Hunt as COO and Jon Snodgres as CFO, said Walter C. Herlihy, Ph.D.,

President and CEO of Repligen. We are encouraged by the quarter s performance, which was driven by strong sales of Protein A affinity ligands and increased demand for our chromatography products.

Repligen Reports Second Quarter 2014 Financial Results

Total revenue for the second quarter of 2014 was comprised of bioprocessing product revenue only. Total

revenue for the second quarter of 2013 was $17.5 million, which included royalty and other revenue of $4.5 million; $4.3 million of this was royalty revenue from Bristol-Myers Squibb based on its U.S. sales of Orencia under an agreement that expired on December 31, 2013. Operating expenses for the three-month period ended June 30, 2014 were $12.4 million compared to $11.4 million for the same period

in 2013, an increase of $1.0 million or 9.1%. This increase was primarily driven by higher cost of goods associated with higher product sales and increased selling, general and administrative (SG&A) expenses, partially offset by decreased

research and development (R&D) expenses and the absence of cost of royalty. During the second quarter of 2014, SG&A included approximately $300,000 of expenses associated with our June 2, 2014 acquisition of the business of Refine

Technology and increased expenses related to the expansion of the Company s management team and commercial operations. Research and development expense (R&D) decreased by $876,000 or 38% during the second quarter of 2014 compared with same

period in 2013, primarily due to the Company s investment during the 2013 period in therapeutic development programs that have since been discontinued. Earnings per diluted share were $0.09 for the second quarter of 2014 compared to $0.14 for

the same period in 2013.

Year-to-Date Financial Summary:

Product revenue for the six-month period ended June 30, 2014 was $29.9 million compared to $24.9 million for the same period in 2013, an increase of 20%.

Product gross profit was $16.9 million or 56% of product revenue for the 2014 period compared to $12.8 million or 51% of revenue during 2013, an increase of 32%. Total revenue for the six-month period ended June 30, 2014 was $31.9 million

compared to $34.0 million for the same period in 2013, a decrease of 6%. Operating expenses for the six-month period of 2014 were $23.5 million, including approximately $500,000 in transaction expense associated with the Refine acquisition, compared

to $24.3 million for the 2013 period, a decrease of 4%. Operating income for the six-month period ended June 30, 2014 was $8.4 million compared to $9.6 million for the same period in 2013. Net income for the six-month period ended June 30,

2014 was $7.1 million compared to $6.9 million for the same period in 2013. Earnings per diluted share for the six-month period ended June 30, 2014 were $0.22 compared to $0.21 for the 2013 period.

Financial Guidance for 2014

Today we are revising our

financial guidance for the year 2014 based on our expectations for our bioprocessing business, which includes the ATF System through our recent acquisition of the business of Refine Technology. The following guidance is based on expectations for our

existing business and does not include the impact on our revenue and expenses of potential milestone payments from therapeutic out-licenses, the financial impact of additional potential acquisitions or fluctuations in foreign currency exchange

Repligen Reports Second Quarter 2014 Financial Results

Recent Business Updates

Repligen Reports Second Quarter 2014 Financial Results

Repligen will host a conference call and webcast today, August 11, at 8:30 a.m. EDT, to discuss second 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 77432919. 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 77432919.

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 (Open-Platform User-Specified) that we deliver

prepacked 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 receipt of any future payments under the terms of our agreement with Pfizer and our agreement with BioMarin, 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

Repligen Reports Second Quarter 2014 Financial Results

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-Meyers 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 Second Quarter 2014 Financial Results

REPLIGEN CORPORATION

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