ADC Therapeutics SA announced it has entered an exclusive license agreement with Mitsubishi Tanabe Pharma Corporation (MTPC) for the development and commercialization of ZYNLONTA® (loncastuximab tesirine-lpyl) for all hematologic and solid tumor indications in Japan. Under the terms of the agreement, ADC Therapeutics will receive an upfront payment of $30 million and up to an additional $205 million in milestones if certain development and commercial events are achieved. ADC Therapeutics will also receive royalties ranging in percentage from the high teens to the low twenties based on net sales of the product in Japan.

MTPC will conduct clinical studies of ZYNLONTA in Japan and will have the right to participate in any global clinical studies of the product by bearing a portion of the costs of the study. ZYNLONTA® is a CD19-directed antibody drug conjugate (ADC). Once bound to a CD19-expressing cell, ZYNLONTA is internalized by the cell, where enzymes release a pyrrolobenzodiazepine (PBD) payload.

The potent payload binds to DNA minor groove with little distortion, remaining less visible to DNA repair mechanisms. This ultimately results in cell cycle arrest and tumor cell death. The U.S. Food and Drug Administration (FDA) has approved ZYNLONTA (loncastuximab tesirine-lpyl) for the treatment of adult patients with relapsed or refractory (r/r) large B-cell lymphoma after two or more lines of systemic therapy, including DLBCL not otherwise specified, DLBCL arising from low-grade lymphoma and also high-grade B-cell lymphoma. The trial included a broad spectrum of heavily pre-treated patients (median three prior lines of therapy) with difficult-to-treat disease, including patients who did not respond to first-line therapy, patients refractory to all prior lines of therapy, patients with double/triple hit genetics and patients who had stem cell transplant and CAR-T therapy prior to their treatment with ZYNLONTA.

This indication is approved by the FDA under accelerated approval based on overall response rate and continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial. ZYNLONTA is also being evaluated as a therapeutic option in combination studies in other B-cell malignancies and earlier lines of therapy.