Shares of NextCure (NASDAQ: NXTC) rose up 8% in premarket trading after the company announced a strategic partnership with Simcere Zaiming to develop SIM0505, a novel antibody-drug conjugate (ADC) targeting CDH6 for solid tumors. SIM0505 is currently in Phase 1 testing in China, and a U.S. trial is expected to begin in the third quarter of 2025.

NextCure will gain global rights to SIM0505 outside Greater China, while Simcere retains rights in that region. The agreement also gives NextCure access to Simcere’s proprietary linker and TOPOi payload for use in a second ADC program directed at a NextCure target.

“We believe SIM0505 has the potential to be an important new therapy for cancer patients,” said Michael Richman, president and CEO of NextCure. “Partnering with Simcere Zaiming provides us with an opportunity to advance a class-leading ADC directed to CDH6.”

“SIM0505 is a significantly differentiated CDH6 targeting ADC candidate independently developed by Simcere Zaiming,” added Renhong Tang, CEO of Simcere Zaiming. “Together, we aim to accelerate drug development to benefit more cancer patients worldwide.”

Simcere Zaiming is eligible for milestone payments up to $745 million and tiered royalties on sales outside Greater China. Initial U.S. clinical data is expected in the first half of 2026.