IDEAYA Biosciences and Hengrui Pharmaceuticals Present Oral Presentation on IDE849 at IASLC 2025 World Conference on Lung Cancer

IDEAYA Biosciences and Jiangsu Hengrui Pharmaceuticals will present data from a Phase 1 trial of IDE849 (SHR-4849), a potential first-in-class DLL3-TOP1 ADC, in over 70 small-cell lung cancer patients. The trial data will be presented at the IASLC 2025 World Conference on Lung Cancer. A U.S. Phase 1 trial of IDE849 in SCLC patients is set to initiate in Q3 2025.

IDEAYA Biosciences, Inc. (Nasdaq: IDYA) and Jiangsu Hengrui Pharmaceuticals Co., Ltd. (Hengrui) have announced that they will present data from a Phase 1 trial of IDE849 (SHR-4849), a potential first-in-class delta-like ligand 3 (DLL3)-targeting Topoisomerase-1 (TOP1) payload antibody drug conjugate (ADC), at the IASLC 2025 World Conference on Lung Cancer. The conference will take place from September 6 to 9, 2025, in Barcelona, Spain.

The data will cover clinical efficacy and safety results in over 70 small-cell lung cancer (SCLC) patients from Hengrui's ongoing, multi-site, open-label Phase 1 trial. The presentation will focus on results from the dose escalation and multiple expansion doses, including patients from a U.S. Phase 1 trial of IDE849 in SCLC patients initiated in the third quarter of 2025.

IDEAYA Biosciences and Hengrui are committed to advancing the global development of IDE849, which represents a potential first-in-class DLL3-TOP1 ADC. The drug is designed to target DLL3, which is upregulated across multiple solid tumor types, including SCLC, neuroendocrine tumors (NETs), non-small cell lung cancer (NSCLC), and melanoma.

In addition to the oral presentation, IDEAYA will also present a poster with data from a second published abstract. This abstract will provide combination mechanism and preclinical synergy data between TOP1-payload based ADCs and IDE161, a proprietary PARG inhibitor developed by IDEAYA. The combination has the potential to enhance the durability of TOP1-payload based ADCs, including IDE849 and IDE034, a B7H3/PTK7 bispecific TOP1 ADC.

"We are excited to have the first-in-human Phase 1 clinical efficacy and safety data presented by our partner Hengrui for IDE849 (SHR-4849) in SCLC patients at the WCLC 2025," said Dr. Darrin Beaupre, M.D., Ph.D., Chief Medical Officer of IDEAYA Biosciences. "IDE849 represents a potential first-in-class DLL3-TOP1 ADC, and we look forward to evaluating its clinical potential as both a monotherapy agent in SCLC and NET patients, as well as in combination with immunotherapy and our Phase 1 PARG inhibitor, IDE161," added Yujiro S. Hata, President and Chief Executive Officer of IDEAYA Biosciences.

The oral presentation will be titled "A first-in-human Phase 1 study of SHR-4849 (IDE849), a DLL3-directed antibody drug conjugate (ADC) in relapsed SCLC" and will take place on Sunday, September 7th, from 4:45 PM to 6:00 PM CET. The poster presentation will be titled "Dual PARG-TOP1 Inhibition Exacerbates DNA-Protein Crosslinks and Replication Stress: A Promising Strategy for Enhancing TOP1i-ADC Efficacy" and will be presented by Reeja Maskey, Ph.D., on Monday, September 8th, from 10:30 AM to 12:00 PM CET.

Both the oral presentation and poster will be available online at [https://ir.ideayabio.com/events](https://ir.ideayabio.com/events) following the conference.

References:
[1] https://www.prnewswire.com/news-releases/ideaya-biosciences-and-hengrui-pharmaceuticals-announce-oral-presentation-at-iaslc-2025-world-conference-on-lung-cancer-for-ide849-shr-4849-a-potential-first-in-class-dll3-top1-adc-302510323.html
[2] https://www.marketscreener.com/news/ideaya-biosciences-and-hengrui-pharmaceuticals-announce-oral-presentation-at-iaslc-2025-world-confer-ce7c5cddda8ef322