ADC Therapeutics SA and Swedish Orphan Biovitrum AB announced the European Commission (EC) has granted conditional marketing authorization for the use of ZYNLONTA® (loncastuximab tesirine) for the treatment of relapsed or refractory diffuse large B-cell lymphoma (DLBCL). The approval follows a positive opinion issued in September by the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA). Sobi expects to commence launching ZYNLONTA upon completion of the marketing authorization transfer.

The approval is based on data from LOTIS-2, a large (n=145) Phase 2 multinational, single-arm clinical trial of ZYNLONTA for the treatment of adult patients with relapsed or refractory DLBCL following two or more prior lines of systemic therapy. In April 2021, the U.S. Food and Drug Administration (FDA) granted accelerated approval of ZYNLONTA as the first CD19-targeted antibody drug conjugate (ADC) as a single-agent treatment for adult patients with relapsed or refractory DLBCL after two or more lines of systemic therapy. Earlier 2022, ADC Therapeutics announced an exclusive license agreement with Sobi to develop and commercialize ZYNLONTA for all hematologic and solid tumor indications in Europe and select international territories.

Under the terms of the agreement, the EC approval of ZYNLONTA triggers a $50 million milestone payment from Sobi to ADC Therapeutics. The EC decision is valid in all European Union Member States, Iceland, Norway, and Liechtenstein. The EC granted conditional marketing authorization for ZYNLONTA for this indication and continued approval may be contingent upon verification in a confirmatory trial.

As a routine part of the marketing authorization process, the EMA's Committee for Orphan Medicinal Products reviewed ZYNLONTA's orphan designation and decided not to uphold it.