Repligen Corporation 41 Seyon Street Building #1, Suite 100 Waltham, Massachusetts 02453 Repligen Reports Third Quarter 2022 Financial Results and Updates Full Year 2022 Financial Guidance Reports revenue of $200.7 milli

Repligen Reports Third Quarter 2022 Financial Results

and Updates Full Year 2022 Financial Guidance

WALTHAM, Mass. November 1, 2022 Repligen Corporation (NASDAQ:RGEN), a life sciences company focused on bioprocessing

technology leadership, today reported financial results for its third quarter of 2022. Provided in this press release are financial highlights for the three- and nine- month periods ended September 30, 2022, updates to our financial guidance

for the year 2022 and access information for today s webcast and conference call.

Tony J. Hunt, President and Chief Executive Officer said,

I m very pleased with our performance for the third quarter, with reported revenue of $201 million reflecting overall revenue growth of approximately 13% year-over-year, and 19% at constant currency. We continue to see strength

in our base business, where third quarter revenue grew 29% year-over-year, and is expected to be in the range of 33%-34% for the full year. Strategically, we executed on two important deals, signing a 15-year agreement with DRS Daylight Solutions on real-time process monitoring using mid-infrared technology and more recently extending our affinity ligand relationship with

Purolite (an EcoLab company) until 2032. We are confident about our full year outlook for the company with overall revenue growth of 19%-20% as reported and 24%-25%

at constant currency.

Financial Highlights for the Third Quarter and First Nine Months of 2022

GROSS PROFIT and GROSS MARGIN

All reconciliations of GAAP to adjusted

(non-GAAP) figures above, as well as EBITDA to adjusted EBITDA, are detailed in the reconciliation tables included later in this press release.

Financial Guidance for 2022

Our financial guidance for

the fiscal year 2022 is based on expectations for our existing business and includes the financial impact of our 2021 acquisitions. This guidance also excludes the impact of potential additional acquisitions and future fluctuations in foreign

currency exchange rates.

Our non-GAAP guidance for the fiscal year

2022 excludes the following items:

Our non-GAAP guidance for the fiscal year 2022 includes:

All reconciliations of GAAP

to adjusted (non-GAAP) guidance are detailed in the tables included later in this press release.

Repligen will host a conference call and webcast today, November 1, 2022, at 8:30 a.m. EDT, to discuss

third quarter 2022 financial results, financial guidance and corporate developments. The conference call will be accessible by dialing toll-free (844) 274-3999 for domestic callers or (412) 317-5607 for international callers. No passcode is required for the live call. In addition, a webcast will be accessible via the Investor Relations section of the Company s website. Both the conference call and

webcast will be archived for a period of time following the live event. The replay dial-in numbers are (877) 344-7529 from the U.S., (855)

669-9658 from Canada and (412) 317-0088 for international callers. Replay listeners must provide the passcode 7297399.

Non-GAAP Measures of Financial Performance

To supplement our financial statements, which are presented on the basis of U.S. generally accepted accounting principles (GAAP), the following non-GAAP measures of financial performance are included in this release: revenue growth rate at constant currency; adjusted gross profit and adjusted gross margin; adjusted income from operations; adjusted operating

income and adjusted net income; earnings before interest, taxes, depreciation and amortization (EBITDA); adjusted EBITDA; adjusted net income; adjusted net income per share diluted; adjusted fully diluted earnings per share; adjusted cost of

sales; adjusted R&D expense; and adjusted SG&A expense. The Company provides organic revenue growth rates in constant currency to exclude the impact of both foreign currency translation and the impact of acquisition revenue for current year

periods that have no prior year comparable in order to facilitate a comparison of its current revenue performance to its past revenue performance. The Company provides revenue growth rates in constant currency in order to facilitate a comparison of

its current revenue performance to its past revenue performance. To calculate revenue growth rates in constant currency, the Company converts actual net sales from local currency to U.S. dollars using constant foreign currency exchange rates in the

current and prior period.

The Company s non-GAAP financial results and/or

non-GAAP guidance exclude the impact of: acquisition-related inventory step-up costs, acquisition and integration costs, intangible amortization costs, contingent

consideration expenses related to the Company s acquisitions, amortization of debt issuance costs related to Company s convertible debt, non-cash interest expense, loss on conversion of debt, and the

related impact on tax of non-GAAP charges. These costs are excluded because management believes that such expenses do not have a direct correlation to future business operations, nor do the resulting charges

recorded accurately reflect the performance of our ongoing operations for the period in which such charges are recorded.

A reconciliation of GAAP to

adjusted non-GAAP financial measures is included as an attachment to this press release. When analyzing the Company s operating performance and guidance investors should not consider non-GAAP measures as substitutable for the comparable financial measures prepared in accordance with GAAP.

About Repligen Corporation

Repligen Corporation is a global company that develops and commercializes highly innovative bioprocessing technologies and systems that enable efficiencies in

the process of manufacturing biological drugs. We are inspiring advances in bioprocessing for the customers we serve; primarily biopharmaceutical drug developers and contract development and manufacturing organizations (CDMOs) worldwide. Our focus

areas are Filtration, Chromatography, Process Analytics, Fluid Management and Proteins. Our corporate headquarters are located in Waltham, Massachusetts, with additional administrative and manufacturing operations worldwide. The majority of our

manufacturing sites are located within the U.S. (California, Massachusetts, New Hampshire, New Jersey and New York), and we also have sites in Estonia, France, Germany, Ireland, the Netherlands and Sweden. For more information about the company,

constitutes a Safe Harbor statement under the Private Securities Litigation Reform Act of 1995: This press release contains forward-looking statements, which are made pursuant to the safe harbor provisions of federal securities laws,

including 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, including, without limitation, express or implied statements or guidance regarding current or future financial performance and position, including cash and investment position, demand in the markets in which we operate, the expected

performance of our business, the expected performance and success of our strategic partnerships including recently announced agreements with Daylight Solutions and Purolite, the expected performance of our acquired businesses, our ability to

continue to generate, and the magnitude of, COVID-related revenue, and management s strategy, plans and objectives for operations or acquisitions, product development and sales, selling, general and administrative expenditures, constitute

forward-looking statements identified by words like believe, expect, may, will, should, seek, anticipate, projected, estimated or

could and similar expressions. Forward-looking statements are neither historical facts nor assurances of future performance. Because forward-looking statements relate to the future, they 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 the following: the effect of the COVID-19 coronavirus pandemic, including

mitigation efforts and economic effects, on our business operations and the operations of our customers and suppliers; the ultimate impact of the COVID-19 coronavirus pandemic on our business or financial

results; 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;

our ability to successfully integrate any acquired businesses into our business and achieve the expected benefits of such acquisitions; reduced demand for our products that adversely impacts our future revenues, cash flows, results of operations and

financial condition; our ability to compete with larger, better financed bioprocessing, pharmaceutical and biotechnology companies; our compliance with all U.S. Food and Drug Administration and EMEA regulations; our volatile stock price; and other

risks detailed in Repligen s Annual Report on Form 10-K for the year ended December 31, 2021 and in subsequently filed reports with the Securities and Exchange Commission (the Commission), including

our Quarterly Reports on Form 10-Q on file with the Commission. Actual results may differ materially from those Repligen contemplated by these

forward-looking statements. Therefore, you should not rely on any of these forward-looking statements. These forward-looking statements reflect management s current views, expectations, and

assumptions regarding the future of our business, future plans and strategies, projections, anticipated events and trends, the economy and other future conditions, and are based only on information currently available to us. Repligen does not

undertake to update, whether written or oral, any of these forward-looking statements to reflect a change in its views or events or circumstances, whether as a result of new information, future development or otherwise, that occur after the date

hereof except as required by law.

Global Head of Investor Relations

REPLIGEN CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited, amounts in thousands, except share and per share data)

REPLIGEN CORPORATION

RECONCILIATION OF GAAP INCOME FROM OPERATIONS TO

NON-GAAP (ADJUSTED) INCOME FROM OPERATIONS

(Unaudited, amounts in thousands)

REPLIGEN CORPORATION

RECONCILIATION OF GAAP NET INCOME TO NON-GAAP (ADJUSTED) NET INCOME

(Unaudited, amounts in thousands)

REPLIGEN CORPORATION

RECONCILIATION OF GAAP NET INCOME PER SHARE TO

NON-GAAP (ADJUSTED) NET INCOME PER SHARE

Totals may not add due to rounding.

REPLIGEN CORPORATION

RECONCILIATION OF GAAP NET INCOME TO ADJUSTED EBITDA

(Unaudited, amounts in thousands)

REPLIGEN CORPORATION

RECONCILIATION OF GAAP COST OF SALES TO NON-GAAP (ADJUSTED) COST OF SALES

(Unaudited, amounts in thousands)

REPLIGEN CORPORATION

RECONCILIATION OF GAAP R&D EXPENSE TO NON-GAAP (ADJUSTED) R&D EXPENSE

(Unaudited, amounts in thousands)

REPLIGEN CORPORATION

RECONCILIATION OF GAAP SG&A EXPENSE TO NON-GAAP (ADJUSTED) SG&A EXPENSE

(Unaudited, amounts in thousands)