Zai Lab to Present Updated Phase 1 Data on DLL3-Targeted ADC Zocilurtatug Pelitecan (ZL-1310) at the 2025 AACR-NCI-EORTC International Conference
Zai Lab Limited announced that new data from its global Phase 1 clinical trial (NCT06179069) evaluating zocilurtatug pelitecan (zoci), formerly known as ZL-1310, has been selected for an oral presentation at the 2025 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, scheduled for October 22–26, 2025, in Boston, Massachusetts. The presentation, designated as a late-breaking abstract, will feature updated follow-up data from patients enrolled in the ongoing study, further advancing the understanding of this promising first-in-class therapy.
Advancing a Novel DLL3-Targeted ADC for SCLC
Zocilurtatug pelitecan (zoci) is Zai Lab’s potential first- and best-in-class antibody-drug conjugate (ADC) targeting Delta-like ligand 3 (DLL3), a protein highly expressed in small cell lung cancer (SCLC). The therapy is being developed to address a critical unmet need for patients with extensive-stage small cell lung cancer (ES-SCLC) who have progressed following prior platinum-based chemotherapy.
The ongoing global Phase 1 clinical trial is assessing the safety, tolerability, and antitumor activity of zoci across multiple dosing cohorts in patients who have relapsed after standard treatment. Conducted at several international clinical sites, this study is designed to define the optimal therapeutic window and establish the recommended dose for future pivotal trials.
“The critical need for expanded treatment options for patients with small cell lung cancer propels our strategy to advance zoci as a novel therapeutic option as quickly as possible,” said Rafael G. Amado, M.D., President and Head of Global Research and Development at Zai Lab. “We remain on track to initiate our Phase 3 registrational study in previously treated SCLC by year-end. We look forward to sharing the updated results that demonstrate zoci’s continued potential at the upcoming AACR-NCI-EORTC International Conference.”
Presentation Details at AACR-NCI-EORTC 2025
The oral presentation will be delivered by Dr. Grace K. Dy of the Roswell Park Comprehensive Cancer Center in Buffalo, New York, during the Plenary Session 3: Antibody Drug Conjugates on Friday, October 24, 2025, from 9:17 a.m. to 9:27 a.m. ET, followed by a panel discussion from 9:27 a.m. to 9:45 a.m. ET. The session will take place at the Hynes Convention Center, Level 3, Ballroom AB, in Boston.
Presentation details:
- Title: Phase 1 trial of ZL-1310, a DLL3-targeted ADC, in patients with previously treated extensive-stage small cell lung cancer
- Presenter: Grace K. Dy, M.D., Roswell Park Comprehensive Cancer Center, Buffalo, NY
- Session: Plenary Session 3: Antibody Drug Conjugates
- Date/Time: Friday, October 24, 2025 | 9:17–9:27 a.m. ET (presentation); 9:27–9:45 a.m. ET (panel)
- Location: Hynes Convention Center, Level 3, Ballroom AB
Investor Webcast and Conference Call
To complement the data presentation, Zai Lab will host an investor webcast and conference call to discuss the latest findings from the zoci Phase 1 trial and to outline the next steps in clinical development.
Details are as follows:
- Date/Time: October 24, 2025 | 11 a.m. ET / 11 p.m. HKT
- Webcast link: Zai Lab Investor Presentation
- Dial-in registration: Conference Registration
- Presenter: Rafael G. Amado, M.D., President and Head of Global Research and Development, Zai Lab
Participants are required to complete online registration before joining the call. A replay of the webcast will be made available on the company’s website shortly after the live event.
Understanding Small Cell Lung Cancer (SCLC)
Small cell lung cancer (SCLC) is among the most aggressive and lethal solid tumors, representing approximately 15% of all lung cancer diagnoses worldwide—equating to roughly 2.5 million cases annually. Despite being initially responsive to chemotherapy, the majority of SCLC patients relapse within months, and the prognosis remains poor. Approximately two-thirds of all patients are diagnosed with extensive-stage disease, where the cancer has spread beyond the lungs, limiting curative treatment options.
While immunotherapy has modestly extended survival for a subset of patients, the overall landscape of SCLC treatment remains dominated by high relapse rates and limited therapeutic innovation. This underscores the urgent need for novel, targeted modalities capable of selectively eradicating tumor cells while sparing healthy tissue—a gap that zoci seeks to address.
The Promise of DLL3 as a Therapeutic Target
Delta-like ligand 3 (DLL3) is a cell-surface antigen found to be overexpressed in neuroendocrine tumors, including SCLC. DLL3 is largely absent from normal adult tissues, making it an attractive target for therapeutic intervention. High levels of DLL3 expression are also correlated with poor clinical outcomes, further reinforcing its potential as a biomarker-driven target in oncology.
By selectively binding to DLL3-positive tumor cells, zocilurtatug pelitecan is designed to deliver a highly potent cytotoxic payload directly into the tumor microenvironment, reducing off-target toxicity while maximizing tumor cell killing.
Inside Zocilurtatug Pelitecan (zoci): A Next-Generation ADC
Zocilurtatug pelitecan (zoci) is a humanized anti-DLL3 monoclonal antibody conjugated via a cleavable linker to a novel camptothecin derivative, a topoisomerase I inhibitor. This design leverages a proprietary ADC technology platform called TMALIN®, which is engineered to overcome the limitations of first-generation ADCs.
The TMALIN® platform optimizes payload release within the tumor microenvironment, enhancing selectivity and stability in circulation while maintaining strong cytotoxic activity upon internalization. This innovation aims to balance efficacy and tolerability—two critical factors that have historically challenged ADC development in solid tumors like SCLC.
The Phase 1 clinical study is providing essential safety and pharmacokinetic data to guide the development of zoci’s Phase 3 registrational trial, which Zai Lab plans to initiate by the end of 2025.
In January 2025, the U.S. Food and Drug Administration (FDA) granted Orphan Drug Designation (ODD) to zoci, recognizing its potential to benefit patients with small cell lung cancer—a rare and devastating malignancy with few effective treatments. This designation provides incentives including market exclusivity, tax credits, and potential fee waivers, underscoring the clinical significance of Zai Lab’s ADC program.
Zai Lab’s Broader Oncology Vision
The development of zoci is a cornerstone of Zai Lab’s oncology portfolio, reflecting the company’s long-term commitment to addressing cancers with high unmet medical need. By combining global innovation with deep expertise in translational medicine, Zai Lab is accelerating the development of first-in-class and best-in-class therapies across multiple oncology indications.
“Zoci represents not just an exciting new treatment avenue for SCLC, but also an embodiment of our broader mission—to bring transformative therapies to patients who urgently need them,” Dr. Amado added. “Our focus is on rapidly and rigorously advancing promising science from early discovery through clinical validation.”
About Zai Lab
Zai Lab Limited (NASDAQ: ZLAB; HKEX: 9688) is a global, research-driven biopharmaceutical company headquartered in China and the United States, focused on discovering, developing, and commercializing innovative therapies in oncology, immunology, neuroscience, and infectious diseases. Through a collaborative model of in-house innovation and global partnerships, Zai Lab aims to bridge the gap between leading-edge science and accessible, high-impact healthcare solutions.
The company’s pipeline spans multiple therapeutic areas and includes a diverse range of clinical and preclinical programs, many of which target diseases with limited or no approved treatment options.
