Repligen Corporation 41 Seyon Street Building #1, Suite 100 Waltham, Massachusetts 02453 Telephone: (781) 250-0111 Telefax: (781) 250-0115 Repligen Reports Full Year and Fourth Quarter 2013 Financial Results - 2013 Produ

Repligen Reports Full Year and Fourth Quarter 2013 Financial Results

- 2013 Product Revenue Growth of 13.5% -

- Year-over-Year Net Income Up 13.7% to $16.1 Million -

- Earnings Conference Call and Webcast Today at 9:00 a.m. EST -

WALTHAM, MA March 6, 2014 Repligen Corporation (NASDAQ:RGEN) today reported financial results for the full year and fourth quarter

ended December 31, 2013. Below are the Company s financial and business highlights for these periods, followed by financial guidance for the year 2014 and access information for today s webcast and conference call.

2013 Financial Highlights

Operating expenses for the twelve-month period ended December 31, 2013 were $45.3 million compared to $51.2 million for the year 2012, a decrease of $5.9

million or 11.5%. This decrease was driven by a 9.9% reduction in cost of product revenue to $22.5 million and a 30.0% decrease in research and development (R&D) expense to $7.3 million. The decrease in cost of product revenue was generally the

result of improved capacity utilization and process yields. The decrease in R&D expense was primarily the result of lower spending on clinical development programs since the Company s strategic realignment to focus on building its

bioprocessing business. For the year 2013, sales, general and administrative (SG&A) expense decreased by $526,000 or 4.0%.

Repligen Reports Full Year and Fourth Quarter 2013 Financial Results

Walter Herlihy, Ph.D., President and CEO of Repligen said, 2013 was an exceptional year for Repligen,

during which we met or exceeded our financial goals while building value for our key customers and shareholders. Our financial performance was highlighted by strong top-line results, and substantial margin expansion. Strategically, Repligen is now

established as a pure play bioprocessing company following our decision in 2012 to divest our therapeutic development programs.

2013 Financial Highlights

Bioprocessing product revenue for the fourth quarter of 2013 was $10.4 million compared to $9.7 million for the same period

in 2012, an increase of 6.6%. Total revenue for the fourth quarter of 2013 was $15.4 million compared to $18.8 million for the same period in 2012, a decrease of 18.2%. This decrease was primarily the result of a $5.0 million upfront payment from

Pfizer, Inc. ( Pfizer ) recognized during the 2012 period under the terms of an outlicensing agreement for the Company s spinal muscular atrophy (SMA) clinical development program. Operating expenses for the fourth quarter of 2013

were $10.2 million compared to $12.4 million for the same period in 2012, a decrease of $2.2 million or 17.8%. Approximately $1.3 million of this decrease was the result of reduced cost of product revenue, which declined 21.8%. This reduction

resulted in product gross margin of 55.3% compared to 39.0% for the same period in 2012. For the fourth quarter of 2013 compared to the same period in 2012, R&D expense decreased by $921,000 or 39.3%, and SG&A expense increased by $113,000

or 3.5%. Net income for the fourth quarter of 2013 was $3.3 million, a decrease from $9.6 million for the same period in 2012. During the 2013 quarter, we recorded an $800,000 provision based on an ongoing tax audit to determine whether certain

historical R&D tax credits will prevail. During the fourth quarter of 2012, we recognized a $3.0 million tax benefit from our U.S. net operating losses (NOLs). Earnings per diluted share for the fourth quarter of 2013 were $0.10 compared to

$0.30 for the same period in 2012.

Recent Business Updates

Repligen Reports Full Year and Fourth Quarter 2013 Financial Results

Financial Guidance for 2014

The following guidance for the year 2014 is based on expectations for our existing business and does not include the impact on our revenue and expenses of

potential milestone payments from Pfizer or BioMarin, potential bioprocessing acquisitions or fluctuations in foreign currency exchange rates.

Repligen will host a conference call and webcast today, March 6, at 9:00 a.m. EST, to discuss full year and fourth quarter 2013 financial results and

corporate developments. The live call can be accessed by dialing (866) 318-8620 for domestic callers or (617) 399-5139 for international callers. Dial-in participants must provide the passcode 47036442. Alternatively, an audio webcast will

be accessible via the Investor section of Repligen s website www.repligen.com. Both the conference call and webcast will be archived for a period of time following the live event. The replay dial-in numbers are (888) 286-8010 for

domestic callers and (617) 801-6888 for international callers. Replay listeners must provide the passcode 50353989.

Repligen Reports Full Year and Fourth Quarter 2013 Financial Results

About Repligen Corporation

Repligen Corporation (NASDAQ:RGEN) is a life sciences company focused on the development, production 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 growth factor products are used to increase cell growth and product yield during the fermentation stage of biologic drug manufacturing. In addition, we

developed and market an innovative line of plug-and-play chromatography columns named OPUS (Open Platform User Specified) that we deliver pre-packed to our biopharmaceutical customers with their 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.

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 and chromatography products, our expected launch of

large-scale pre-packed chromatography columns and suitability for larger-scale manufacturing, plans and objectives for future operations, optimization of manufacturing process and assurance of GMP compliance resulting from facility expansion, 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 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-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 ability to

successfully integrate Repligen Sweden AB, including achieving manufacturing efficiencies at Repligen Sweden AB; our ability to optimize manufacturing process; 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.

Repligen Reports Full Year and Fourth Quarter 2013 Financial Results

Director Investor Relations

Repligen Corporation

Repligen Reports Full Year and Fourth Quarter 2013 Financial Results

REPLIGEN CORPORATION

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