#1Investor Presentation August 17, 2021 R REPLIGEN INSPIRING ADVANCES IN BIOPROCESSING CA 19 8 8 R REPLIGEN OPUS 80R N System (1#2#3#4Repligen - A Bioprocessing Innovator Enabling efficient, single-use, high productivity biological drug manufacturing 37% 5-year Revenue CAGR (2015-2020) Consistently above average industry growth $3.7B+ Total Addressable Market An expanding portfolio scaling into clinical and commercial manufacturing Expanding applications Serving multiple biological drug classes Monoclonal antibodies Gene therapy COVID-related vaccines and therapeutics Highly differentiated portfolio through M&A and R&D Advancing disruptive technologies with market leadership positions RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING 1,465 Employees 530K+ Sq. Ft. Mftg. (6.30.21) Investing in talent, systems & capacity >300 new employees 1H 21 3 Site Buildouts Ongoing (US, Ireland) 4#5#6#7Strong Biologics Markets R REPLIGEN#8#9#10#11#12#13#14Our Most Recent Acquisition Polymem SA July 1, 2021 jil PROGR TIT wi Surine Say Showe 2020 % Revenue by Geography Core technology and innovation in hollow fiber membrane and modules (ultra/microfiltration) Immediately increases HF membrane capacity by 3x Creates two customer focus areas within Polymem Industrial and Municipal (Polymem Sales Force) Bioprocessing (Repligen Sales Force) 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Compliments our TFF Systems offerings KrosFlo® HF TFF Systems, ProConnex® Fluid Management, 100% consumables ● 28% 70% Europe US ■ ROW 22% R REPLIGEN INSPIRING ADVANCES IN BIOPROCESSING 78% *excludes any sales to Repligen Castanet-Tolosan, France polymem MEMBRANE MANUFACTURER 2021 Revenue est. ~$7M* Life Sciences/Hospital OEM Industrial/Municipal 0#15#16Scaling our Business R REPLIGEN#17#18#19#20Second Quarter 2021 Financial Highlights O Record Quarterly Revenue - Strong Base, COVID tailwinds ○ $163M; +86% overall, +69% organic I. BASE: 31 pts. of growth II. COVID: 42 pts. of growth III. M&A: 13 pts. of growth Gross Margin and Operating Margin Expansion o GAAP GM: 62% (from 57.9% Q2 '20) o Adjusted GM: 62% (from 58.2% Q2 '20) o GAAP Op. Margin: 29.6% (from 22.3% Q2 '20) o Adjusted Op. Margin: 34.7% Adjusted (from 29.2% Q2 '20) Net Income Per Share (EPS) Growth o Fully diluted EPS: $0.64 GAAP (from $0.30 Q2 '20) o Adjusted Fully diluted EPS $0.79 (from $0.42 Q2 '20) M&A, 7% $0.90 $0.80 $0.70 $0.60 $0.50 $0.40 $0.30 $0.20 $0.10 $0.00 BASE, 66% $0.42 Q2 '20 RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING COVID, 27% $0.79 Q2 '21 Q2 2021 Revenue Composition Q2 2021 Adj. EPS 20#21#22Financial Snapshot ($s Millions except EPS) Revenue Revenue Growth Gross Margin (GAAP) Gross Margin (Adj.) 2019 $270.2 39%, 33% organic 55.9% 57.0% $36.1 $63.5 $21.4 $52.5 $0.44 $1.07 $528.4 49.2 $71.1 2020 $366.3 36%, 29% organic 57.2% 57.6% $69.8 $98.1 $60.0 $89.1 $1.11 $1.65 $717.3 53.9 $107.9 2021 Guidance* $625-$645 71-76%, 57%-62% organic 59%-60% 59%-60% $156-$161 $192-$197 $118-$122 $154-$158 $1.67-$1.74 $2.71-$2.78 $740-$750 57.0 $210-$215 Operating Income (GAAP) Operating Income (Adj.) Net Income (GAAP) Net Income (Adj.)¹ EPS diluted (GAAP) EPS diluted (Adj.)¹ Cash and Cash Equiv. YE Fully diluted shares YE (M) EBITDA (Adj.)² * FY 2021 Guidance as of 07/27/21 earnings call 1. Change in accounting for the treatment of tax on certain intangible amortization was made in 2019 2. Non-GAAP financial measure; see reconciliation tables in appendix 2020 Revenue Splits Consumables/Equipment ~77%/22% ~80%/20% ~70%/30% Biopharma/CDMO Clinical/Commercial RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING Additional 2021 Guidance* COVID-related revenue R&D % of revenue: Adj. tax rate: Cap Ex: $170-$180M 5.5%-6.0% 19% $55-$60 22#23Well Positioned for Sustainable Growth (0) Four main franchises focused on technology leadership High impact systems and consumable products for flexible manufacturing; single-use and continuous solutions Total addressable market: ~$3.7B Expanding manufacturing capacity to stay ahead of increasing demand. R&D engine for next-generation products Strong end market acceleration, diversification Growth Rates 2021e by Franchise FILTRATION >100% ANALYTICS 30%-35% CHROMA 35%-45% PROTEINS >30% RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING Cash & Equivalents $740M-$750M YE 2021e 2024 Revenue Goal $1.0 Billion 23#24Appendix R REPLIGEN#25#26Monoclonal Antibody (mAb) Bioprocessing Workflow Cell Culture Seed Train XCell ATFⓇ Growth Factors 2 PL Production XCell ATFⓇ Clarification / Cell Harvest Centrifugation KrosFlo® TFF KrosFlo® TFDFⓇ ProConnexⓇ SPECTRUM TF DF Depth Filtration Sterile Filtration KrosFlo® TFDFⓇ ProConnex® R R REPLIGEN Purification Polish Capture Chromatography Chromatography ODE OPUSⓇ PPC Ligands, Resins R REPLIGEN OPUS® PPC VPE Devices Flow VPE Viral Filtration VPE Devices RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING OPP Formulation Concentration Buffer Exchange KrosFlo® TFF TangenX® TFF ProConnex® Fill and Finish mid VPE Devices VPE Devices 26#27#28#29#30#31#322020 & 2019 Reconciliation GAAP to Non-GAAP Net Income Per Share Reconciliation of GAAP Net Income per Share to Non-GAAP (Adjusted) Net Income per Share (Unaudited) GAAP Net Income per Share - DILUTED Adjustments to Net Income per Share - DILUTED Acquisition and integration costs Inventory step-up charges. Intangible amortization. Loss on extinguishment of debt Non-cash interest expense Tax effect of intangible amortization and acquisition costs Adjusted Net Income per Share - DILUTED Totals may not add due to rounding $ $ $ $ Ś $ $ $ Twelve Months Ended December 31, 2020 1.11 0.19 0.01 0.30 0.20 (0.17) $1.65 $ $ $ $ $ $ $ $ 2019 0.44 0.26 0.03 0.27 0.11 0.15 (0.20) 1.07 RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING 32#332020 & 2019 Reconciliation EBITDA to Adjusted EBITDA Reconciliation of GAAP Net Income to Adjusted EBITDA (Unaudited, amounts in thousands) GAAP Net Income Adjustments Investment Income Interest expense Tax Provision Depreciation Intangible amortization EBITDA Other Adjustments Acquisition and integration costs Loss on extinguishment of debt Inventory step-up charges Adjusted EBITDA $ $ $ $ $ $ $ $ $ $ $ Twelve Months Ended December 31, 2020 59,926 (1,741) 12,133 (709) 10,888 16,143 96,640 10,479 734 107,853 $ $ Ś $ $ $ $ $ $ $ $ 2019 21,411 (5,324) 9,292 4,740 7,317 13,551 50,987 13,008 5,650 1,483 71,128 RREPLIGEN INSPIRING ADVANCES IN BIOPROCESSING 33#34#35Q2 2021 vs. Q2 2020 Reconciliation Operating Income, Net Income Per Share REPLIGEN CORPORATION RECONCILIATION OF GAAP INCOME FROM OPERATIONS TO NON-GAAP (ADJUSTED) INCOME FROM OPERATIONS (Unaudited, amounts in thousands) GAAP INCOME FROM OPERATIONS ADJUSTMENTS TO INCOME FROM OPERATIONS: Inventory step-up charges Acquisition and integration costs Intangible amortization ADJUSTED INCOME FROM OPERATIONS $ Totals may not add due to rounding Three Months Ended June 30, 2021 48,240 $ 3,218 5,161 2020 19,537 2,134 3,874 Six Months Ended June 30, 2021 $ 84,623 $ 1,598 5,769 10,323 2020 31,443 4,687 7,752 $ 56,619 $ 25,545 $ 102,313 $ 43,882 REPLIGEN CORPORATION RECONCILIATION OF GAAP NET INCOME PER SHARE TO NON-GAAP (ADJUSTED) NET INCOME PER SHARE (Unaudited) GAAP NET INCOME PER SHARE - DILUTED $ ADJUSTED NET INCOME PER SHARE - DILUTE $ Totals may not add due to rounding. Three Months Ended June 30, 2021 ADJUSTMENTS TO NET INCOME PER SHARE - DILUTED: Inventory step-up charges Acquisition and integration costs Intangible amortization Loss on conversion of debt Non-cash interest expense Tax effect of non-GAAP charges 0.64 $ 0.06 0.09 0.00 0.05 (0.05) 0.79 R REPLIGEN INSPIRING ADVANCES IN BIOPROCESSING $ 2020 0.30 $ 0.04 0.07 0.05 (0.04) 0.42 $ Six Months Ended June 30, 2021 1.16 0.03 0.10 0.18 0.00 0.10 (0.10) 1.47 $ $ 2020 0.48 0.09 0.15 0.10 (0.08) 0.74 35#36#37