ADC Therapeutics SA

Disclosure Controls and Procedures

Our management, under the supervision and with the participation of our Chief Executive Officer and Chief Financial Officer, has performed an evaluation of our disclosure controls and procedures (as defined in Rule 13a-15(e) under the

Exchange Act) as of the end of the period covered by this report, as required by Rule 13a-15(b) under the Exchange Act. Based upon this evaluation, our Chief Executive Officer and Chief Financial Officer, has concluded that, as of the end of the period covered by this Quarterly Report, our disclosure controls and procedures were effective in ensuring that the information required to be disclosed by us in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified by the SEC’s rules and forms, and that the information required to be disclosed by us in the reports that we file or submit under the Exchange Act is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure.

Changes in Internal Control Over Financial Reporting

There were no changes to internal control over financial reporting during the quarter ended March 31, 2026, that would have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.