ADC Therapeutics Partner Files for ZYNLONTA Approval in Japan

ADC Therapeutics SA announced that its Japanese licensing partner, Tanabe Pharma Corporation, filed a marketing authorization application with Japan's Ministry of Health, Labor and Welfare on October 29, 2026. The application seeks approval for ZYNLONTA (loncastuximab tesirine-lpyl) to treat adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) following two or more lines of systemic therapy.

Additionally, Tanabe Pharma entered into an exclusive sublicensing agreement with Nippon Shinyaku Co., Ltd. for the commercialization of ZYNLONTA in Japan, bringing specialized oncology and hematology capabilities to support its potential introduction.

Clinical Background and Study Results

The regulatory filing follows encouraging data from the Phase 1/2 MT-2111-A-101 bridging study evaluating ZYNLONTA monotherapy in Japanese patients, which were recently presented at the Japanese Society of Hematology meeting. Key reported findings include:

• Overall Response Rate: 58.1% in the Phase 2 portion in Japan.
• Complete Response Rate: 41.9%.
• Duration of Response: Median duration was not reached at a median follow-up of 15.21 months.

Tanabe Pharma reported that these findings aligned with the global pivotal LOTIS-2 study without identifying new safety signals.

Partnership Structure and Next Steps

Under the existing agreements:

• Tanabe Pharma remains responsible for ongoing development and securing regulatory approval in Japan.
• Nippon Shinyaku will utilize its established commercial and field medical presence to support commercialization upon approval.
• Near-term corporate milestones for ADC Therapeutics include filing acceptance and eventual first commercial sales within the partner territory.

Practical Implications and Verification

Patients and stakeholders should note that the filing represents an application for review rather than a final product approval. Official updates regarding regulatory status can be monitored through corporate announcements on the ADC Therapeutics investor relations website or regulatory notices issued by Japan's Ministry of Health, Labor and Welfare.