The CD19-targeted antibody drug conjugate (ADC) was granted accelerated approval by the US regulator based on overall response rate.
The approval also covers patients with DLBCL arising from low grade lymphoma and high-grade B-cell lymphoma.
“This is the first ever approval of a PBD based ADC,” noted Chris Martin, CEO, ADC Therapeutics, on a conference call about the regulatory development and commercial launch.
The Lausanne, Switzerland based biotech is now entering "the next phase of transformation and growth," he added.
Dr Paolo F Caimi, University Hospitals Cleveland Medical Center and Case Comprehensive Cancer Center, Case Western Reserve University, said there is a significant unmet need for treatment options for patients with r/r DLBCL, including those who have been heavily pretreated and have difficult-to-treat disease.
“Single-agent ZYNLONTA (loncastuximab tesirine-lpyl) demonstrated clinically important outcomes in the pivotal LOTIS-2 study across several disease subtypes. Notably, this included transplant eligible and ineligible patients and patients who previously received stem cell transplant or CAR-T cell therapy.”
Results from the LOTIS-2 trial demonstrated an overall response rate (ORR) of 48.3% - 70 out of 145 patients, which included a complete response (CR) rate of 24.1% - 35 out of 145 patients, and a partial response (PR) rate of 24.1% - 35 out of 145 patients.
Patients had a median time to response of 1.3 months and the median duration of response for the 70 responders was 10.3 months.
ADC Therapeutics is now preparing the US commercial launch of the drug, which is delivered in a 30-minute IV infusion, every 21 days.
Jennifer Herron, chief commercial officer (CCO) at the biotech, on the the conference call, said: “We estimate [that there are] approximately,10,500 third line plus DLBCL patients in the US and the European 5 for a third line plus market opportunity in excess of US$1bn. Importantly we have a number of ongoing and planned trials to potentially expand into additional histologies and earlier lines of therapy representing additional business opportunities.”
As part of the rollout of the therapy in the US, the biotech is establishing a comprehensive patient support program offering financial assistance, ongoing education and other resources to eligible patients who are prescribed ZYNLONTA.
“Seamless distribution, patient access and support services are all critical to ensure that all patients who may benefit from ZYNLONTA have the opportunity to receive it as soon as possible. We are on track to make it commercially available next week,” continued Herron.
In terms of pricing, she said the wholesale acquisition cost (WAC) for a 10mg vial of the drug is US$23,500 which points towards “the differentiated value of ZYNLONTA and is consistent with payer stakeholder expectations reflected in our extensive market research.”