ArriVent Announces IND Clearance for Novel Tetravalent MUC16/NaPi2b Targeting ADC ARR-002 with Initial Focus in Ovarian and Endometrial Cancers

• Superior efficacy and favorable tolerability in animal models support the potential of ARR-002 to overcome limitations of single-target approaches
• Phase 1 initiation expected in the second half of 2026

NEWTOWN SQUARE, Pa., May 07, 2026 — ArriVent BioPharma, Inc. (Company or ArriVent) (Nasdaq: AVBP), a clinical-stage company dedicated to accelerating the global development of innovative biopharmaceutical therapeutics, today announced clearance of an investigational new drug (IND) application by the United States Food and Drug Administration (FDA) for ARR-002, a potential first-in-class MUC16/NaPi2b targeting tetravalent antibody-drug conjugate (ADC) with an initial focus in ovarian and endometrial cancers and broader therapeutic potential across solid tumors.

“We are pleased to advance ARR-002 into the clinic as the second next-generation ADC from our portfolio,” said Stuart Lutzker, MD, Ph.D., President of Research and Development of ArriVent. “At AACR, compelling preclinical data was presented demonstrating ARR-002’s potential to improve safety and efficacy over conventional single-target and bivalent bispecific ADCs in ovarian and endometrial cancers. ARR-002’s dual-target approach is designed to improve delivery and reduce off-tumor toxicity to overcome key limitations of single-target ADCs, including limited internalization, suboptimal payload delivery, and heterogeneous target expression. We expect to initiate a Phase 1 trial and dose the first patient in the second half of the year.”

MUC16 and NaPi2b are highly expressed on ovarian and endometrial cancers with limited expression in normal tissues, making them strong co-targets. Select preclinical data included in the IND submission of ARR-002 was presented at the 2026 American Association for Cancer Research (AACR) Annual Meeting in a joint presentation with Aarvik Therapeutics demonstrating:

• Effective binding to individual targets, simultaneous engagement of both targets, and enhanced internalization vs. single-target antibody controls
• Superior in vivo efficacy vs. single-target ADCs in the OVCAR-3 xenograft model
• The potential for a wider therapeutic window based on a favorable tolerability profile in cynomolgus monkeys, consisting of reversible hematologic findings at a higher maximum tolerated single dose vs. other approaches in development

About ArriVent

ArriVent is a clinical-stage biopharmaceutical company dedicated to the identification, development, and commercialization of differentiated medicines to address the unmet medical needs of patients with cancers. ArriVent seeks to utilize its team’s deep drug development experience to maximize the potential of its lead development candidate, firmonertinib, and advance a pipeline of novel therapeutics, such as next-generation antibody drug conjugates, through approval and commercialization.

About ARR-002

ARR-002 (also known as AV-P138-ADC) is a first-in-class, Mucin-16 (MUC16) and sodium-dependent phosphate transport protein 2b (NaPi2b) dual-target, tetravalent (2+2 format) ADC, with site-specific conjugation to vcMMAE at a drug-to-antibody ratio (DAR) of 4. Both these cell surface antigens are expressed in ovarian and endometrial cancers with limited expression in normal tissues, making them strong co-targets.