#1R REPLIGEN INSPIRING ADVANCES IN BIOPROCESSING Investor Presentation April 2022 SAF REC ES R REPLIGEN I D OPUS 60R HE#2Safe Harbor / Non-GAAP Measures This presentation contains forward-looking statements within the meaning of the federal securities laws. Statements in this presentation which are not strictly historical statements including, without limitation, express or implied statements or guidance regarding Repligen's estimated financial results for full-year 2022, future financial performance and other statements identified by words like "estimated," "anticipated," "guidance," or "goal," and similar expressions are forward- looking statements. These statements are subject to risks and uncertainties which may cause our plans to change or actual results to differ materially from those anticipated. In particular, unforeseen events outside of our control may adversely impact future results. Additional information concerning these factors is discussed in our reports filed with the Securities and Exchange Commission including recent Form 8-Ks, our most recent Annual Report on Form 10K and our most recent Quarterly Reports on Form 10Q, all of which are available on our website. The forward-looking statements in this presentation reflect management's current views and may become obsolete as a result of new information, future events or otherwise. We may not update such forward looking statements to reflect a change of events or circumstances that occur after the date hereof, except as required by law. The industry and market data contained in this presentation are based on management's own estimates, independent publications, government publications, reports by market research firms or other published independent sources, and, in each case, are believed by management to be reasonable estimates. Although we believe these sources are reliable, we have not independently verified the information. This presentation discloses certain financial measures not prepared in accordance with generally accepted accounting principles, or GAAP. Repligen strongly encourages investors to review our consolidated financial statements and publicly filed reports in their entirety and cautions investors that the non-GAAP measures used herein may differ from similar measures used by other companies, even when similar terms are used to identify such measures. → REPLIGEN 2#3Repligen Snapshot We are enabling efficient, single-use, flexible manufacturing of biological drugs, providing first-to-market solutions for bioprocessing challenges $671M Revenue 2021 Bioprocessing solutions provider with differentiated technologies → REPLIGEN +45% 5-year CAGR +36% ex-COVID Growing through innovation, acquisitions, market strength ~39% Revenue 2021 from new markets (COVID & GT) ~60% mAbs Diversified customer base, across all biological drug modalities 10 Disruptive technologies since 2014 Drives innovation, first- to-market position, market leadership; accounts for ~25% of our revenue in 2021 >$8B TAM New applications Capacity expansion >1,800 employees Taking share in a robust and expanding global biologics market 3#4Robust and Expanding Global Biologics Market COVID Vax and Tx Cell & Gene Therapy Monoclonal Antibodies Exosomes, Oligonucleotides, mRNA (beyond COVID) Global Commercial Market (2020) >$90B (2021) >$5B (Cell & Gene) ~$150B (~6% biosimilars) JA ww Projected Market Growth (2020-2025) N/A >25% 10%-12% (15%+ biosimilars) Commercial and Clinical Activity for Future Growth 6 FDA approved YE 2021 7 FDA approved YE 2021 (3 GT, 4 CAR-T) >120 FDA approved YE 2021 Emerging opportunities >1,000 clinical trials >1,200 clinical trials US (2020) >800 clinical trials (2020) Data sources: Company filings/guidance; U.S. FDA website; clinicaltrials.gov; Industry articles incl. www.genengnews.com/a-lists/top-11-best-selling-covid-19-vaccines-and-drugs-of-h1-2021/, Antibodies to Watch in 2021 https://pubmed.ncbi.nlm.nih.gov/33459118/; PHrMA report https://phrma.org/-/media/Project/PhRMA/PhRMA-Org/PhRMA-Org/PDF/A-C/MID-cell-and-gene-therapy-2020.pdf; Alliance for Regenerative Medicine report H1 2021 "A Year of Firsts and Records"; Repligen internal mAbs tracker; Market research reports (Research and Markets, Allied Market Research, Brandessence Research, Fortune Business Highlights, Qualiket Research. R REPLIGEN Repligen 2021 Revenue by Biologic Type 28% 11% 61% www $190M $76M $405M TOTAL: $671M 4#5#6#7M&A is Accelerating Expansion, Elevating our Presence We continue to pursue strategic acquisitions that meet our strict criteria: ■ Technology leadership ▪ Strengthens, expands Repligen's market position Underinvested in a key area Strong revenue growth, margins in line with or above corporate average Potential to be accretive to adjusted EPS in first full year post-acquisition → REPLIGEN Analytics Areas of Investment to Accelerate Growth Commercial Operations R&D Acquisition C Technologies May 2019 Highly differentiated, in-line, real-time, fast and accurate measurement; analytics entry ARTESYN Biosolutions December 2020 Premier integrated systems for filtration and chromatography Polymem S.A. June 2021 World class hollow-fiber; immediately expands HF capacity 3x-4x Avitide Inc. Sept. 2021 Leading-edge content player; largest most diverse ligand library, gene-therapy affinity resin focus Filtration Chromatography Proteins & Affinity Resins 7#8#9#10#11#12#13#14#15#16#17#18#19#20#21#22#23#24#25#26#27#28