AN4005, a drug candidate discovered in-house, is an oral small-molecule PD-L1 inhibitor designed to induce and stabilize PD-L1 dimerization and thereby disrupt the interaction between PD-1 and PD-L1. Compared to the crowded anti-PD-1/PD-L1 antibodies space, small-molecule PD-L1 inhibitors are in early stages of development with no drug yet on the market. Small molecule PD-L1 inhibitors have lower production costs, and shorter half-life that may allow for dose titration and schedule modifications to minimize immune-related adverse events.

In preclinical studies, AN4005 was well tolerated and exhibited tumor growth inhibition (TGI) similar to FDA-approved anti-PD-L1 antibody. In addition, the anti-tumor activities of AN4005 were demonstrated to be dependent on the immune system.

First in Human, Dose Escalation Study of AN4005 (NCT04999384)

AN4005 is currently being evaluated in a Phase I, multi-center, open-label clinical trial study in patients with advanced solid tumors, designed to determine the recommended Phase 2 dose (RP2D) and maximum tolerated dose (MTD). This study is being conducted in the US and China planned to enroll 31–36 patients.  At the conclusion of this trial, a dose expansion phase of this study will be conducted to confirm the RP2D/MTD.