ZYNLONTA, also known by its generic name loncastuximab tesirine-lpyl, is a CD19-directed antibody drug conjugate. The U.S. Food and Drug Administration originally approved it in April 2021 for adults with relapsed or refractory large B-cell lymphoma after two or more lines of systemic therapy.
ZYNLONTA combines an antibody that targets CD19 with a cytotoxic component. The antibody component helps direct the medicine toward CD19-expressing B cells, while the attached payload is designed to damage the targeted cells. This approach represents one application of antibody drug conjugate technology, which seeks to combine targeted recognition with delivery of a potent therapeutic agent.
Research and development surrounding ZYNLONTA has included clinical trials examining its activity in patients with difficult-to-treat B-cell lymphomas. Important areas of investigation include:
The FDA granted the original approval under the accelerated approval pathway, based on overall response rate. A confirmatory trial was required to verify and describe clinical benefit.
ADC Therapeutics focuses on developing antibody drug conjugates for cancer treatment. ZYNLONTA is a major example of its research approach, particularly in hematologic malignancies. Continued development can provide information about how the therapy performs in broader treatment settings and in combination with other medicines.
In June 2026, ADC Therapeutics reported topline results from the Phase 3 LOTIS 5 confirmatory trial evaluating ZYNLONTA with rituximab in relapsed or refractory diffuse large B-cell lymphoma. The company reported that the study achieved statistical significance for its primary progression-free survival endpoint and reported no detrimental effect on the key secondary overall survival endpoint.
Key areas of ongoing scientific interest include:
The development of ZYNLONTA also illustrates how targeted cancer medicines can progress from laboratory research through clinical trials and regulatory review. FDA records continue to identify its approved use for adults with relapsed or refractory large B-cell lymphoma following at least two previous systemic treatment lines.
Overall, ZYNLONTA research represents an important area within antibody drug conjugate development. Its clinical development has involved evaluating targeted delivery, treatment response, safety, and combination strategies in B-cell lymphoma. ADC Therapeutics' continuing research and reported clinical findings provide additional information about the medicine's role and the broader potential of ADC technology. Such research is important for understanding how targeted therapies may continue to evolve in hematologic cancer treatment.