Exhibit 99.1

Repligen Reports First Quarter 2025 Financial Results

WALTHAM, Mass., April 29, 2025 -- Repligen Corporation (NASDAQ:RGEN), a life sciences company focused on bioprocessing technology leadership, today reported financial results for its first quarter of 2025, covering the three-month period ended March 31, 2025. The company is also providing updated financial guidance for the full year 2025.

Olivier Loeillot, President and Chief Executive Officer of Repligen said, “We had a strong start to the year with $169 million of revenue, which represented 14% organic non-COVID growth and helped drive meaningful adjusted operating margin expansion. Total orders grew nearly 20%, with all four franchises growing double-digits, highlighting the momentum in our business. As a result, we are confident in our organic growth outlook for the full year. Strategically, we strengthened our Analytics franchise with the acquisition of 908’s bioprocessing portfolio. Finally, we are working to navigate through the current economic environment and at this point in time, we see minimal impact from tariffs on our EPS.”

Q1 2025 BUSINESS HIGHLIGHTS

FINANCIAL PERFORMANCE

Q1 2025 financial performance (compared to prior year periods except as noted).

All adjusted figures are non-GAAP and, except for earnings per share, are rounded to the nearest million, and are reconciled in the tables included later in this press release.

MARGIN SUMMARY

Cash and cash equivalents at March 31, 2025, were $697 million, compared to $757 million at December 31, 2024.

FINANCIAL GUIDANCE FOR FISCAL YEAR 2025

Our financial guidance for the fiscal year 2025 is based on expectations for our existing business. Our GAAP and Adjusted (non-GAAP) guidance excludes the impact of any potential business acquisitions in 2025, tariffs, and future fluctuations in foreign currency exchange rates.

Updated guidance incorporates the impact of the acquisition of 908 Devices’ Bioprocessing Analytics business including: a revenue increase of $10 million, a $4 million reduction in income from operations and the associated impact on operating margin, adjusted EBITDA margin, net income and earnings per share, diluted. Additionally, there is a 100-basis point increase in gross margin versus our prior guidance. This primarily relates to a shift in costs to operating expenses from cost of goods sold, where they previously were assumed in our prior guidance. There is no impact on operating income associated with this change.

Conference Call and Webcast Access

Repligen will host a conference call and webcast today, April 29, 2025, at 8:30 a.m. ET, to discuss first quarter 2025 financial results, corporate developments and financial guidance for the year 2025. 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 6386085.

About Repligen Corporation

Repligen Corporation is a global life sciences 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 and Fluid Management, Chromatography, Process Analytics and Proteins. Our corporate headquarters are located in Waltham, Massachusetts, and the majority of our manufacturing sites are in the

U.S., with additional key sites in Estonia, France, Germany, Ireland, the Netherlands and Sweden. For more information about the company see our website at www.repligen.com, and follow us on LinkedIn.

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 Adjusted (non-GAAP) measures of financial performance are included in this release: organic non-COVID revenue and non-COVID revenue growth; organic revenue and organic revenue growth; adjusted cost of goods sold, adjusted gross profit and adjusted gross margin; adjusted R&D expense and adjusted SG&A expense; adjusted income from operations and adjusted operating margin; adjusted pre-tax income; adjusted net income; adjusted earnings per share (diluted); adjusted earnings before interest, taxes, depreciation and amortization (EBITDA), and adjusted EBITDA margin. The Company provides the impact of foreign currency translation, to enable determination of revenue growth rates at constant currency. To calculate the impact of foreign currency translation, the Company converts actual net sales from local currency to U.S. dollars using constant foreign currency exchange rates in the current and prior year periods.

The Company’s non-GAAP financial results and/or non-GAAP guidance exclude the impact of: acquisition and integration costs; restructuring charges including the costs of severance and accelerated depreciation among other charges; incremental costs attributed to CEO transition; contingent consideration related to the Company’s acquisitions; intangible amortization costs; non-cash interest expense related to the accretion of the debt discount; amortization of debt issuance costs related to Company’s convertible debt; foreign currency impact of certain intercompany loans; 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.

NOTE:

All reconciliations of above GAAP figures (reported or guidance) to adjusted (non-GAAP) figures are detailed in the tables included later in this press release. When analyzing the Company’s operating performance and guidance, investors should not consider non-GAAP measures as a substitute for the comparable financial measures prepared in accordance with GAAP.

Forward-Looking Statements

This press release contains forward-looking statements, which are made pursuant to and in reliance upon the safe harbor provisions of federal securities laws, including the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Any statements contained herein which do not describe historical facts, including, among others, any express or implied statements or guidance regarding current or future financial performance and position, including our 2025 financial guidance and related assumptions; expected demand in the markets in which we operate; expectations regarding the acquisition of 908 Devices’ bioprocessing portfolio; and the expected performance of our business and momentum across our portfolio, are based on management’s current expectations and beliefs and are forward-looking statements which involve risks and uncertainties that could cause actual results to differ materially from those discussed in such forward-looking statements.

Such risks and uncertainties include, among others, our ability to successfully grow our bioprocessing business; our ability to manage through and predict headwinds; the risk that we have assumed that markets and franchises will improve and grow more than expected; our ability to achieve our 2025 financial guidance; our ability to develop and commercialize products and the market acceptance of our products; our ability to successfully integrate any acquired businesses and relevant personnel in a timely manner or at all, and to achieve the expected benefits of such acquisitions; that demand for our products could decline, which could adversely impact our future revenues, cash flows, results of operations and financial condition; our ability to compete with larger, better financed bioprocessing companies; risks around the Company’s effectiveness of disclosure controls and procedures and the effectiveness of our internal control over financial reporting; our compliance with all U.S. Food and Drug Administration and European Medicines Evaluation Agency regulations; our volatile stock price; the impact of tariffs on our business, and other risks and uncertainties detailed in Repligen’s filings with the U.S. Securities and Exchange Commission (the Commission), including our Annual Report on Form 10-K for the year ended December 31, 2024 and in subsequently filed reports with the Commission, including our Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, and any subsequent filings made with the Commission, which are available at the Commission’s website at www.sec.gov. Actual results may differ materially from those Repligen contemplated by these forward-looking statements, which 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 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. Repligen disclaims any obligation to update or revise any such statements to reflect any

change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Repligen Contact:

Jacob Johnson

VP, Investor Relations

(781) 419-0204

investors@repligen.com

REPLIGEN CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

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

REPLIGEN CORPORATION

RECONCILIATIONS OF GAAP TO NON-GAAP FINANCIAL MEASURES

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

In all tables below, totals may not add due to rounding

Reconciliation of Total Revenue (GAAP) Growth to Organic Non-COVID Revenue Growth (Non-GAAP)

Reconciliation of Income from Operations (GAAP) to Adjusted Income from Operations (Non-GAAP)

Reconciliation of Net Income (GAAP) to Adjusted Net Income (Non-GAAP)

Reconciliation of Earnings Per Share (GAAP) to Adjusted Earnings Per Share (Non-GAAP)

Reconciliation of Net Income (GAAP) to Adjusted EBITDA (Non-GAAP)

Reconciliation of Cost of Goods Sold (GAAP) to Adjusted Cost Goods Sold (Non-GAAP)

Reconciliation of R&D Expense (GAAP) to Adjusted R&D Expense (Non-GAAP)

Reconciliation of SG&A Expense (GAAP) to Adjusted SG&A Expense (Non-GAAP)

Reconciliation of Net (Loss) Income (GAAP) Guidance to Adjusted Net Income (Non-GAAP) Guidance

Reconciliation of Earnings Per Share (GAAP) Guidance to Adjusted Earnings Per Share (Non-GAAP) Guidance

FOOTNOTES FOR ALL TABLES ABOVE (amounts in thousands):