ArriVent reports Phase 1 data for CDH17 ADC ARR-217 in GI cancers

ArriVent BioPharma announced initial Phase 1 results on October 25, 2026 for ARR-217, also known as MRG007, a cadherin-17-targeting antibody-drug conjugate developed with Lepu Biopharma Co., Ltd., in patients with gastrointestinal malignancies.¹ The data were presented in an oral session at the European Society for Medical Oncology Congress 2026.¹

The trial, registered as NCT07066657, is an ongoing multicenter, open-label Phase 1 study in the US and China assessing safety, tolerability, efficacy, and pharmacokinetics of ARR-217 in patients with unresectable, locally advanced, or metastatic solid tumors, focused initially on colorectal, pancreatic, and other GI cancers.¹ As of the August 5, 2026 cutoff, 123 patients with heavily pretreated GI malignancies had been treated across six dose levels from 2 mg/kg to 8 mg/kg, including 113 with colorectal cancer.¹

At the 6 mg/kg Q3W dose, the objective response rate in pretreated colorectal cancer patients was 44.8% (13/29), including 7 confirmed partial responses, with a 93.1% disease control rate. At doses of 4 mg/kg Q3W and higher, the ORR was 34.2% (25/73) with a 91.8% DCR.¹ Across all doses, 30.1% (37/123) of patients had grade 3 or higher treatment-related adverse events, most commonly neutropenia (12.2%) and diarrhea (8.9%). No grade 5 events or interstitial lung disease were observed.¹

ARR-217 has moved into a Phase 1b dose optimization stage testing 5 and 6 mg/kg Q3W, with further data expected in 2027.¹ ArriVent holds exclusive rights to develop and commercialize ARR-217 worldwide outside Greater China under its collaboration agreement with Lepu Biopharma Co., Ltd.¹