NextCure and Simcere Zaiming Announce Expansion of Ongoing Phase 1 Trial of SIM0505 (CDH6 ADC) into the United States

• First U.S. patient dosed at a mid-tier dose level where multiple responses have been observed
• Multi-regional trial to accelerate time to proof-of-concept data in 1H 2026

BELTSVILLE, Md. and SHANGHAI, Oct. 16, 2025 (GLOBE NEWSWIRE) — NextCure, Inc. (Nasdaq: NXTC), a clinical-stage biopharmaceutical company committed to developing novel therapies to treat cancer, and Simcere Zaiming, an oncology-focused biopharmaceutical company and a subsidiary of Simcere Pharmaceutical Group Ltd (HKEX: 2096), today announced that the first patient in the U.S. has been dosed with SIM0505 in the ongoing Phase 1 trial (NCT06792552), which is evaluating safety, tolerability, pharmacokinetics and efficacy in patients with advanced solid tumors.

SIM0505 is a novel antibody drug conjugate directed to cadherin-6 (CDH6 ADC), featuring a proprietary topoisomerase 1 inhibitor (TOPOi) payload, designed for broad anti-tumor activity, high systemic clearance and an improved potential therapeutic window. NextCure has now expanded the ongoing Phase 1 dose escalation study, which was initiated in China, by enrolling patient(s) in the U.S. into a mid-tier dose level while dose escalation is currently advancing in China. NextCure acquired an exclusive global license, excluding Greater China, for SIM0505 from Simcere Zaiming.

“We are pleased by the significant progress achieved by our partner, which has enabled us to start U.S. enrollment at doses within a therapeutic range where clinical responses have already been observed. Based on current data, SIM0505 has been well tolerated with a favorable safety profile,” said Udayan Guha, M.D., Ph.D., NextCure’s chief medical officer. “We believe that SIM0505 has the potential to become a leading ADC targeting CDH6. We look forward to accelerating the ongoing trial and presenting proof-of-concept clinical data in the first half of 2026.”

“Enrollment of the first patient in the U.S. marks a significant milestone in global clinical development of SIM0505. This achievement reflects our ongoing commitment to advancing innovative oncology treatments for patients in China and worldwide,” said Yongyu Wang, M.D., Chief Medical Officer, Simcere Zaiming.”

About NextCure, Inc.
NextCure is a clinical-stage biopharmaceutical company that is focused on advancing innovative medicines that treat cancer patients that do not respond to, or have disease progression on, current therapies, through the use of differentiated mechanisms of actions including antibody-drug conjugates. We focus on advancing therapies that leverage our core strengths in understanding biological pathways and biomarkers, the interactions of cells, including in the tumor microenvironment, and the role each interaction plays in a biologic response. http://www.nextcure.com

About Simcere Zaiming
Simcere Zaiming is an oncology-focused biopharmaceutical company and a subsidiary of Simcere Pharmaceutical Group Limited (HKEX: 2096, “Simcere”). Founded in 2023, Simcere Zaiming dedicated to developing groundbreaking therapies to meet the unmet clinical needs of cancer patients globally. With a robust and innovative R&D pipeline featuring distinct clinical assets, Simcere Zaiming has successfully launched several innovative products in China, including COSELA®, Enweida®, Endostar®, and Enlituo®. The company is determined to deliver potentially transformative treatment options to cancer patients worldwide through its internal R&D, manufacturing, and commercialization capabilities, complemented by strategic collaborations with leading partners.

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NextCure Investor Inquiries
Timothy Mayer, Ph.D.
NextCure, Inc.
Chief Operating Officer
(240) 762-6486
IR@nextcure.com

Simcere Zaiming Contacts
PR contacts: pr@zaiming.com
IR contacts: ir@zaiming.com