In April 2021, the FDA accelerated the approval of Zynlonta (loncastuximab tesirine-lpyl; from ADC Therapeutics SA), an intravenous CD19-directed antibody and alkylating drug conjugate, for the treatment of relapsed (coming back) or refractory large B-cell lymphoma, including unspecified diffuse large B-cell lymphoma (DLBCL), DLBCL arising from low-grade lymphoma, and high-grade B-cell lymphoma, in adults who have received 2 or more systemic therapies.
Zynlonta is the first and only CD19-targeted antibody–drug conjugate that is approved as a single-drug treatment for patients with relapsed or refractory large B-cell lymphoma.
“There is a significant unmet need for treatment options for patients with relapsed/refractory DLBCL, including those who have been heavily pretreated and have difficult-to-treat disease. Single-agent Zynlonta demonstrated clinically important outcomes in the pivotal LOTIS-2 study across several disease subtypes,” said Paolo F. Caimi, MD, University Hospitals Cleveland Medical Center and Case Comprehensive Cancer Center, Case Western Reserve University. He added that this included patients who were eligible or ineligible for a transplant, as well as patients who already had a transplant.
The FDA approval of Zynlonta was based on the LOTIS-2 clinical trial that included 145 adults with relapsed or refractory DLBCL or high-grade B-cell lymphoma who had received 2 or more systemic regimens.
Overall, 48.3% of the patients had a response to treatment with Zynlonta, of which 24.1% were complete responses (no sign of cancer). The average duration of response was 10.3 months.
The most common side effects reported with Zynlonta were low platelets, neutropenia, anemia, hyperglycemia, fatigue, hypoalbuminemia, rash, edema, nausea, and musculoskeletal pain.
