ADCT Investor Call European Hematology Association June 12, 2020 - PowerPoint PPT Presentation

ADCT Investor Call European Hematology Association June 12, 2020 Presented at the Virtual Edition of the 25th European Hematology Association Congress (EHA25 Virtual), June 11 – 21, 2020

This presentation and the accompanying oral presentation have been prepared by ADC Therapeutics SA ("ADC Therapeutics“, “we” or “us”) for informational purposes only and not for any other purpose. Nothing contained in this presentation is, or should be construed as, a recommendation, promise or representation by the presenter or ADC Therapeutics or any officer, director, employee, agent or advisor of ADC Therapeutics. This presentation does not purport to be all‐inclusive or to contain all of the information you may desire. Information provided in this presentation and the accompanying oral presentation speak only as of the date hereof. This presentation includes forward-looking statements, beliefs or opinions, including statements with respect to our business strategies and plans, competitive position and our objectives for future operations and our financial performance. These forward-looking statements involve known and unknown risks and uncertainties, including those described in our filings with the U.S. Securities and Exchange Commission, many of which are beyond our control and all of which are based on our management's current beliefs and expectations about future events. These forward-looking statements include all matters that are not historical facts. Forward-looking statements may and often do differ materially from actual results. No assurance can be given that such future results will be achieved. Such forward-looking statements contained in this document speak only as of the date of this document. We expressly disclaim any obligation or undertaking to update these forward-looking statements contained in this document to reflect any change in our expectations or any change in events, conditions, or circumstances on which such statements are based unless required to do so by applicable law. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements. Certain information contained in this presentation relates to or is based on studies, publications, surveys, and other data derived from third- party sources and our own internal estimates and research. While we believe that these third-party sources to be reliable as of the date of this presentation, we have not independently verified, and we make no representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, all of the market data included in this presentation involves a number of assumptions and limitations, and there can be no guarantee as to the accuracy or reliability of such assumptions. Finally, although we believe our own internal research is reliable, such research has not been verified by any independent source. This presentation shall not constitute an offer to sell or the solicitation of an offer to buy securities, nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. Presented at the Virtual Edition of the 25th European Hematology Association Congress 2 2 (EHA25 Virtual), June 11 – 21, 2020

ADCT Making Progress in 2020 Raised Significant Capital to Fund Our Programs • Successful initial public offering upsized to $267M • Initial $65M tranche of $115M Deerfield convertible debenture Progressing Our Clinical Trials and Pipeline • Lonca oral presentation of Phase II pivotal data in RR DLBCL at virtual EHA • Lonca plus ibrutinib Phase I/II combination data e-poster at EHA • Additional clinical and early pipeline assets moving forward Preparing for Commercial Launch • BLA submission on track for H2 2020 • Commercial buildout underway Presented at the Virtual Edition of the 25th European Hematology Association Congress 3 (EHA25 Virtual), June 11 – 21, 2020

Initia nitial l Result lts of f a Pha Phase 2 2 Stu tudy y of f Lo Loncastuxim imab Tesir irin ine, a Nov Novel l Pyrrolo lobenzodia iazepin ine-Based d Antib tibody-Drug Conjugate, in n Patie tients Wi With th Rela lapsed or Refr fractory y Dif iffuse Large B-Cell La ll Lymphoma Carmelo Carlo-Stella, MD 1 , Pier Luigi Zinzani, MD 2 , Brad Kahl, MD 3 , Paolo F. Caimi, MD 4 , Melhem Solh, MD 5 , Kirit Ardeshna, MD 6 , Anastasios Stathis, MD 7 , Mehdi Hamadani, MD 8 , Weiyun Ai, MD, PhD 9 , Brian Hess, MD 10 , Juan Pablo Alderuccio, MD 11 , Jay Feingold, MD, PhD 12 , David Ungar, MD 12 , Shui He, PhD 12 , Yajuan Qin, MD, PhD 12 , John Radford, MD, FMedSci 13 1 Department of Oncology and Hematology, Humanitas Cancer Center, Humanitas University, Milan, Italy; 2 Institute of Hematology “ Seràgnoli ” University of Bologna, Bologna, Italy; 3 Department of Medicine, Oncology Division, Washington University, St. Louis, MO, USA; 4 University Hospitals Cleveland Medical Center/Case Western Reserve University, Cleveland, OH, USA; 5 Blood and Marrow Transplant Program at Northside Hospital, Atlanta, GA, USA; 6 Department of Hematology, University College London Hospitals NHS Foundation Trust, London, UK; 7 Oncology Institute of Southern Switzerland, Bellinzona, Switzerland; 8 Division of Hematology and Oncology, Medical College of Wisconsin, Milwaukee, WI, USA; 9 Division of Hematology and Oncology, Department of Medicine, University of California, San Francisco, CA, USA; 10 Division of Hematology and Medical Oncology, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA; 11 Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, USA; 12 ADC Therapeutics America Inc., Murray Hill, NJ, USA; 13 University of Manchester and The Christie NHS Foundation Trust, Manchester Academic Health Centre, Manchester, UK Presented at the Virtual Edition of the 25th European Hematology Association Congress (EHA25 Virtual), June 11 – 21, 2020

LOTIS 2 Study Design: Single-arm, Open-label Phase 2 Study Patient population: Primary objective: Patients with R/R DLBCL following ≥2 lines of Evaluate efficacy, using ORR (central review), and prior systemic therapy safety of the full Phase 2 study population 30-min infusion Lonca Q3W for up to 1 year Q12W for up to 3 years 150 µg/kg 75 µg/kg Follow-up First 2 cycles After 2 cycles Futility requirements met: Total enrolment: ORR for first 52 patients 1 145 patients Presented at the Virtual Edition of the 25th European Hematology Association Congress 5 (EHA25 Virtual), June 11 – 21, 2020

LOTIS 2 Trial Included Patients with Poor Prognosis 145 patients were enrolled and received a mean of 4.3 cycles of Lonca (range: 1 – 15) Total Total Patient characteristics Patient treatment history (N=145) (N=145) Female 60 (41.4) No. of previous systemic therapies,* median (range) 3 (2 – 7) Sex, n (%) Male 85 (58.6) Relapse 99 (68.3) 66.0 Refractory † First-line systemic therapy response, n (%) 29 (20.0) Age, years, median (min, max) (23 – 94) Other ‡ 17 (11.7) DLBCL 127 (87.6) Relapse 43 (29.7) Histology, n (%) HGBCL 11 (7.6) Last-line systemic therapy response, ¶ n (%) Refractory † 84 (57.9) PMBCL 7 (4.8) Other ‡ 18 (12.4) Double/triple hit, n (%) 15 (10.3) Yes 25 (17.2) Refractory to all prior therapies, n (%) No 115 (79.3) Double/triple expressor, n (%) 20 (13.8) Other ‡ 5 (3.4) Transformed disease, n (%) 29 (20.0) Allogeneic 2 (1.4) I – II 33 (22.8) Prior stem cell transplant, n (%) Autologous 21 (14.5) Stage, n (%) III – IV 112 (77.2) Both 1 (0.7) Presented at the Virtual Edition of the 25th European Hematology Association Congress 6 (EHA25 Virtual), June 11 – 21, 2020

Total Population ORR 48.3% and CRR 24.1% ORR in the total population was 48.3% (95% CI: 39.9, 56.7) and an additional 15.2% (22 pts) had stable disease 100 Complete Response 90 Partial Response 80 50.4 70 Response (%) 48.3 45.5 (64/127) (70/145) 60 (5/11) 50 40 23.6 24.1 14.3 30 (1/7) 45.5 20 26.8 24.1 10 14.3 0 All patients (N=145) DLBCL-NOS (n=127) HGBCL (n=11) PMBCL (n=7) Presented at the Virtual Edition of the 25th European Hematology Association Congress 7 (EHA25 Virtual), June 11 – 21, 2020

Duration of Response Increases to 10.25 Months as Data Matures Median duration of response was 10.25 months (95% CI: 5.98, – ) 1.0 Censored 0.9 0.8 0.7 0.6 Probability 0.5 0.4 0.3 0.2 0.1 0.0 At risk 70 61 41 36 29 23 17 13 8 5 4 3 3 3 1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time (months) 8 Presented at the Virtual Edition of the 25th European Hematology Association Congress (EHA25 Virtual), June 11 – 21, 2020

Manageable Toxicities and No New Safety Concerns TEAEs of Any Grade in ≥20% of Patients (Safety Analysis Set; N=145) Patients Preferred term The most common grade ≥3 TEAEs (≥10% of patients) n (%) were: Patients with any TEAE 143 (98.6%) • Neutropenia (37 patients; 25.5%) GGT increased 59 (40.7) • Incidence of febrile neutropenia was low Neutropenia 57 (39.3) (5 patients; 3.4%) Thrombocytopenia 48 (33.1) • Thrombocytopenia (26 patients; 17.9%) Fatigue 40 (27.6) Anaemia 38 (26.2) • GGT increased (24 patients; 16.6%) Nausea 34 (23.4) • Anaemia (15 patients; 10.3%) Cough 32 (22.1) Alkaline phosphatase increased 29 (20.0) Peripheral oedema 29 (20.0) Presented at the Virtual Edition of the 25th European Hematology Association Congress 9 (EHA25 Virtual), June 11 – 21, 2020