CStone Pharmaceuticals and Numab Therapeutics AG have entered into an exclusive regional licensing agreement for the development and commercialization of ND021, a potential best-in-class monovalent, tri-specific antibody-based molecule targeting PD-L1, 4-1BB, and human serum albumin (HSA).

Pursuant to the terms of the licensing agreement, CStone will fund the research and development of ND021 up to completion of an initial Phase Ib clinical trial. In exchange, CStone obtains exclusive rights from Numab to develop and commercialize ND021 in Greater China (including Mainland China, Hong Kong, Macau and Taiwan), South Korea and Singapore.

Numab retains all ND021 rights for the rest of the world. Upon completion of CStone's funding period, no further financial obligations will be owed by either party. This collaboration provides CStone with its first access to Numab's novel multi-specific technology platform and Numab the opportunity to bring this innovative drug candidate into this region.

Discovered and engineered using Numab's proprietary λcap™ technology and MATCH™ platform, ND021 is a late-preclinical-stage, monovalent, tri-specific antibody-based molecule (scMATCH3™) that simultaneously targets PD-L1, 4-1BB, and HSA. ND021 is designed to bind to 4-1BB and activate T cells only when engaging with PD-L1 on the surface of tumor cells, potentially preventing liver toxicities observed in patients treated with conventional 4-1BB-agonistic antibodies.

Compared to other PD-L1/4-1BB bispecific antibody candidates, ND021's unique monovalent structure and ultra-high-affinity PD-L1-binding is expected to lead to a significantly broader safety window and higher efficacy. Furthermore, half-life extension via the HSA-binding motif in ND021 enables convenient dosing schedules for patients. ND021 is anticipated to be effective against tumors with a wide range of PD-L1 expression-levels and may overcome primary and/or acquired resistance to anti-PD-1/PD-L1 therapies. Therefore, ND021 represents a leading class of next-generation cancer immunotherapies and a new backbone molecule for combinations.