– First-Quarter GAAP Earnings per Share of $0.50
and Non-GAAP Earnings per Share of $2.34 –

– Repurchased $350 Million of Common Stock
in First Quarter of 2025 –

WILMINGTON, MA, May 7, 2025 – Charles River Laboratories International, Inc. (NYSE: CRL) today reported its results for the first quarter of 2025. For the quarter, revenue was $984.2 million, a decrease of 2.7% from $1,011.6 million in the first quarter of 2024.

The impact of foreign currency translation reduced reported revenue by 0.9%. Excluding this impact, revenue decreased 1.8% on an organic basis driven by declines in all three business segments.

In the first quarter of 2025, the GAAP operating margin decreased to 7.6% from 12.5% in the first quarter of 2024. The GAAP decrease was primarily driven by lower revenue and higher amortization expense related to accelerated amortization of certain CDMO client relationships. On a non-GAAP basis, the first-quarter operating margin increased to 19.1% from 18.5%, driven primarily by the benefit of cost savings resulting from restructuring initiatives, partially offset by lower revenue.

On a GAAP basis, the net income available to common shareholders for the first quarter of 2025 was $25.5 million, or $0.50 per share, a decrease from net earnings of $67.3 million, or $1.30 per diluted share, for the same period in 2024. The GAAP decreases were primarily driven by lower revenue and operating income, including the accelerated amortization of certain CDMO client relationships. The GAAP net income and earnings per share declines were also driven by a loss from certain venture capital and other strategic investments of $0.15 per share in the first quarter of 2025, compared to a gain of $0.08 per share for the same period in 2024.

On a non-GAAP basis, net income was $119.1 million for the first quarter of 2025, an increase of 1.3% from $117.6 million for the same period in 2024. First-quarter diluted earnings per share on a non-GAAP basis were $2.34, an increase of 3.1% from $2.27 per share for the first quarter of 2024. The increases in non-GAAP net income and earnings per share were primarily driven by favorable below-the-line items, including reductions in the tax rate, interest expense, and diluted shares outstanding.

The GAAP and non-GAAP net income and earnings per share also included an increase of $3.4 million, or $0.07 per share, in the first quarter of 2025 from the reduction in depreciation expense related to a change in certain estimates of the useful lives of property, plant, and equipment, effective for fiscal year 2025. The impact of this change was included in the Company’s initial 2025 financial guidance provided in February.

James C. Foster, Chair, President and Chief Executive Officer, said, “The first quarter demonstrated continued signs of demand stabilization, highlighted by a notable improvement in DSA booking activity to the highest level in two years. This positive development was tempered by the general undertone of uncertainty in the broader market environment, which has led us to a balanced yet cautious view of the remainder of the year. Taking these factors into account, we are modestly increasing our financial guidance for 2025.”

"Beyond this year, and in light of the evolving regulatory landscape, we believe our long-standing hallmarks of advancing scientific innovation and driving greater efficiency in our clients' drug development programs will continue to lead to a long runway of future growth opportunities,” Mr. Foster concluded.

Revenue for the RMS segment was $213.1 million in the first quarter of 2025, a decrease of 3.5% from $220.9 million in the first quarter of 2024. The impact of foreign currency translation reduced revenue by 1.0%. Organic revenue decreased by 2.5%, due primarily to the timing of NHP shipments in China and lower revenue for the Cell Solutions business. The decline was partially offset by higher sales of small research models across all geographic areas, principally driven by higher pricing.

In the first quarter of 2025, the RMS segment’s GAAP operating margin increased to 20.5% from 19.5% in the first quarter of 2024. The GAAP operating margin increase was primarily driven by lower costs associated with the Company's restructuring initiatives, including site consolidations costs. On a non-GAAP basis, the operating margin decreased to 27.1% from 27.6%, primarily driven by lower NHP revenue, partially offset by the benefit of cost savings associated with restructuring initiatives.

Revenue for the DSA segment was $592.6 million in the first quarter of 2025, a decrease of 2.1% from $605.5 million in the first quarter of 2024. The impact of foreign currency translation reduced DSA revenue by 0.6% and the divestiture of a small DSA site reduced reported revenue by 0.1%. Organic revenue decreased by 1.4%, driven primarily by lower revenue for discovery services.

In the first quarter of 2025, the DSA segment’s GAAP operating margin decreased to 15.9% from 19.0% in the first quarter of 2024.

The GAAP operating margin decline was primarily driven by lower revenue, higher costs associated with the Company's restructuring initiatives, as well as higher third-party legal costs related to U.S. government investigations into the Company's NHP supply chain. On a non-GAAP basis, the operating margin increased to 23.9% from 23.5% in the first quarter of 2024. The non-GAAP operating margin increase was primarily driven by the benefit of cost savings resulting from the Company's restructuring initiatives, partially offset by lower revenue.

Revenue for the Manufacturing segment was $178.5 million in the first quarter of 2025, a decrease of 3.6% from $185.2 million in the first quarter of 2024. The impact of foreign currency translation reduced Manufacturing revenue by 1.4%. Organic revenue decreased 2.2%, primarily driven by the CDMO and Biologics Testing businesses. This was partially offset by higher revenue in the Microbial Solutions business.

The Manufacturing segment’s GAAP operating margin decreased to (4.8)% from 18.2% in the first quarter of 2024 as a result of lower revenue and higher amortization expense related to accelerated amortization of certain CDMO client relationships. On a non-GAAP basis, the operating margin decreased to 23.1% from 25.3% in the first quarter of 2024, driven primarily by the CDMO business.

During the first quarter of 2025, the Company repurchased 2.1 million shares for a total of $350.0 million. Under its $1.0 billion stock repurchase authorization that was approved on August 2, 2024, Charles River has repurchased a total of 2.6 million shares, and had $549.3 million remaining on the program through March 29, 2025.

The Company is increasing its 2025 financial guidance, which was originally provided on February 19, 2025. The outlook is being increased to primarily reflect improved net bookings in the DSA segment during the first quarter, which are expected to result in incremental DSA revenue this year, particularly during the first half.

The Company’s 2025 guidance for revenue and earnings per share is as follows:

Footnotes to Guidance Table:

(1) Organic revenue growth is defined as reported revenue growth adjusted for completed acquisitions and divestitures, as well as foreign currency translation.

(2) These adjustments include amortization related to intangible assets, inclusive of the acceleration of amortization expense related to certain CDMO client relationships, as well as the purchase accounting step-up on inventory and certain long-term biological assets. In addition, these adjustments include some costs related to the evaluation and integration of acquisitions and divestitures.

(3) These adjustments primarily include site consolidation (including site transition costs), severance, impairment, and other costs related to the Company’s restructuring actions.

(4) Certain venture capital and other strategic investment performance only includes recognized gains or losses on certain investments. The Company does not forecast the future performance of these investments.

(5) These items primarily relate to certain third-party legal costs related to investigations by the U.S. government into the NHP supply chain related to our DSA segment.

Charles River has scheduled a live webcast on Wednesday, May 7th, at 9:00 a.m. ET to discuss matters relating to this press release. To participate, please go to ir.criver.com and select the webcast link. You can also find the associated slide presentation and reconciliations of GAAP financial measures to non-GAAP financial measures on the website.

The Company reports non-GAAP results in this press release, which exclude often-one-time charges and other items that are outside of normal operations. A reconciliation of GAAP to non-GAAP results is provided in the schedules at the end of this press release.

This press release contains non-GAAP financial measures, such as non-GAAP earnings per diluted share, non-GAAP operating income, non-GAAP operating margin, and non-GAAP net income.

Non-GAAP financial measures exclude, but are not limited to, the amortization of intangible assets and the purchase accounting step-up adjustment on inventory and certain long term biological assets, and other charges and adjustments related to our acquisitions and divestitures, including incremental dividends attributable to Noveprim noncontrolling interest holders; expenses associated with evaluating and integrating acquisitions and divestitures, including advisory fees and certain other transaction-related costs, as well as fair value adjustments associated with contingent consideration; charges, gains, and losses attributable to businesses or properties we plan to close, consolidate, or divest; severance and other costs associated with our restructuring initiatives; the write-off of deferred financing costs and fees related to debt financing; investment gains or losses associated with our venture capital and certain other strategic equity investments; certain legal costs in our Microbial Solutions business related to environmental litigation and in our DSA segment related to U.S. government investigations into the NHP supply chain; tax effect of all of the aforementioned matters; and adjustments related to the recognition of deferred tax assets expected to be utilized as a result of changes to the our international financing structure and the revaluation of deferred tax liabilities as a result of foreign tax legislation. This press release also refers to our revenue on both a GAAP and non-GAAP basis: on a non-GAAP basis, we define “organic revenue growth” as reported revenue growth adjusted for foreign currency translation, acquisitions, and divestitures. We exclude these items from the non-GAAP financial measures because they are outside our normal operations. There are limitations in using non-GAAP financial measures, as they are not presented in accordance with generally accepted accounting principles, and may be different than non-GAAP financial measures used by other companies. In particular, we believe that the inclusion of supplementary non-GAAP financial measures in this press release helps investors to gain a meaningful understanding of our core operating results and future prospects without the effect of these often-one-time charges, and is consistent with how management measures and forecasts the Company's performance, especially when comparing such results to prior periods or forecasts. We believe that the financial impact of our acquisitions and divestitures (and in certain cases, the evaluation of such acquisitions and divestitures, whether or not ultimately consummated) is often large relative to our overall financial performance, which can adversely affect the comparability of our results on a period-to-period basis. In addition, certain activities and their underlying associated costs, such as business acquisitions, generally occur periodically but on an unpredictable basis. We calculate non-GAAP integration costs to include third-party integration costs incurred post-acquisition. Presenting revenue on an organic basis allows investors to measure our revenue growth exclusive of acquisitions, divestitures, and foreign currency exchange fluctuations more clearly. Non-GAAP results also allow investors to compare the Company’s operations against the financial results of other companies in the industry who similarly provide non-GAAP results. The non-GAAP financial measures included in this press release are not meant to be considered superior to or a substitute for results of operations presented in accordance with GAAP. The Company intends to continue to assess the potential value of reporting non-GAAP results consistent with applicable rules and regulations. Reconciliations of the non-GAAP financial measures used in this press release to the most directly comparable GAAP financial measures are set forth in this press release, and can also be found on the Company’s website at ir.criver.com.

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the use of words such as “anticipate,” “believe,” “expect,” “intend,” “will,” “would,” “may,”

“estimate,” “plan,” “outlook,” and “project,” and other similar expressions that predict or indicate future events or trends or that are not statements of historical matters. These statements also include statements regarding Charles River’s expectations regarding the availability of Cambodia-sourced NHPs; the impact of the investigations by the U.S. government into the Cambodia NHP supply chain, including but not limited to Charles River’s ability to cooperate fully with the U.S. government; Charles River’s ability to effectively manage any Cambodia NHP supply impact; the projected future financial performance of Charles River and our specific businesses, including our expectations with respect to the impact of NHP supply constraints and our ability to gain market share; earnings per share; operating margin; client demand, particularly the future demand for drug discovery and development products and services, including our expectations for future revenue trends; our expectations with respect to pricing of our products and services; our expectations with respect to future tax rates and the impact of such tax rates on our business; our expectations with respect to the impact of acquisitions and divestitures, including the Noveprim acquisition, on the Company, our service offerings, client perception, strategic relationships, revenue, revenue growth rates, revenue growth drivers, and earnings; the development and performance of our services and products, including our investments in our portfolio; market and industry conditions including the outsourcing of services and identification of spending trends by our clients and funding available to them; ability to gain market share and capitalize on business opportunities; the impact of our restructuring initiatives, including annualized savings; the impact of our stock repurchase authorization; and Charles River’s future performance, including as delineated in our forward-looking guidance, and particularly our expectations with respect to revenue, the impact of foreign exchange, interest rates, enhanced efficiency initiatives. Forward-looking statements are based on Charles River’s current expectations and beliefs, and involve a number of risks and uncertainties that are difficult to predict and that could cause actual results to differ materially from those stated or implied by the forward-looking statements. Those risks and uncertainties include, but are not limited to: NHP supply constraints and the investigations by the U.S. Department of Justice, including the impact on our projected future financial performance, the timing of the resumption of Cambodia NHP imports into the U.S., our ability to manage supply impact, and potential study delays in our DSA segment attributable to NHP supply constraints; changes and uncertainties in the global economy and financial markets; the ability to successfully integrate businesses we acquire, including Noveprim; the timing and magnitude of our share repurchases; negative trends in research and development spending, negative trends in the level of outsourced services, or other cost reduction actions by our clients; the ability to convert backlog to revenue; special interest groups; contaminations; industry trends; new displacement technologies; USDA and FDA regulations; changes in law; continued availability of products and supplies; loss of key personnel; interest rate and foreign currency exchange rate fluctuations; changes in tax regulation and laws; changes in generally accepted accounting principles; disruptions in the global economy caused by geopolitical conflicts; and any changes in business, political, or economic conditions due to the threat of future terrorist activity in the U.S. and other parts of the world, and related U.S. military action overseas. A further description of these risks, uncertainties, and other matters can be found in the Risk Factors detailed in Charles River's Annual Report on Form 10-K as filed on February 19, 2025, as well as other filings we make with the Securities and Exchange Commission. Because forward-looking statements involve risks and uncertainties, actual results and events may differ materially from results and events currently expected by Charles River, and Charles River assumes no obligation and expressly disclaims any duty to update information contained in this press release except as required by law.

Charles River provides essential products and services to help pharmaceutical and biotechnology companies, government agencies and leading academic institutions around the globe accelerate their research and drug development efforts. Our dedicated employees are focused on providing clients with exactly what they need to improve and expedite the discovery, early-stage development and safe manufacture of new therapies for the patients who need them. To learn more about our unique portfolio and breadth of services, visit www.criver.com.

# # #

Investor Contact:    Media Contact:

Todd Spencer    Amy Cianciaruso

Corporate Vice President,    Corporate Vice President,

Investor Relations    Chief Communications Officer

781.222.6455    781.222.6168

todd.spencer@crl.com    amy.cianciaruso@crl.com