Zai Lab Limited (ZLAB) announced that the U.S. Food and Drug Administration has granted Orphan Drug Designation or ODD to ZL-1310, a potential highly active first-in-class DLL3 antibody-drug conjugate (ADC), to treat small cell lung cancer (SCLC).
The FDA decision follows promising data from Zai Lab's ongoing global Phase 1a/1b clinical trial, evaluating ZL-1310 as monotherapy and in combination with atezolizumab, an immune checkpoint inhibitor, for the treatment of extensive-stage or ES-SCLC.
With the ODD, ZL-1310 will be eligible for certain development incentives. These include a waiver of the Prescription Drug User Fee Act registration application fee, tax credits for certain clinical trials and the potential to receive a seven-year U.S. market exclusivity period granted upon product approval.
At present, treatment options are limited for SCLC, one of the most aggressive and lethal solid tumors.
ZL-1310, a novel ADC, targets Delta-like ligand 3 (DLL3), an antigen that is overexpressed in many neuroendocrine tumors, which is typically associated with poor clinical outcomes. It is a validated therapeutic target for SCLC.
ZL-1310 comprises a humanized anti-DLL3 monoclonal antibody linked to a novel camptothecin derivative (a topoisomerase 1 inhibitor) as its payload. The company noted that the compound was designed with a novel ADC technology platform called TMALIN, which leverages the tumor microenvironment to overcome challenges associated with first-generation ADC therapies, including off-target payload toxicity.
Rafael Amado, President, Head of Global Research and Development, Zai Lab, said, "Receiving an Orphan Drug Designation for ZL-1310 recognizes its potential to treat patients with SCLC. These patients have an urgent need for innovative treatment options with improved efficacy, safety and ready access in tertiary care and community settings. ZL-1310 has demonstrated promising objective response rates and a favorable safety profile from the ongoing Phase 1 trial in patients with recurrent SCLC recently disclosed. "
The company said it plans to continue to advance the clinical development of the promising asset across lines of therapy in SCLC and other DLL3-expressing tumors.
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