The agreement positions K2 Therapeutics, a firm established by investment group MPM BioImpact, to advance ATG-106, a CDH6 x CD3 bispecific candidate designed to treat solid tumors. By utilizing Antengene’s proprietary AnTenGager platform, the drug aims to overcome safety challenges common in first-generation TCEs through steric hindrance-based masking and fast on/off CD3 binding kinetics. This design is intended to minimize cytokine release syndrome while maintaining anti-tumor efficacy.

Under the terms of the deal, Antengene will receive approximately USD 20 million in upfront and near-term payments for ATG-106, with potential milestone payouts reaching USD 960.5 million plus tiered royalties. A similar financial structure applies to the second, undisclosed program should K2 exercise its option. This transaction marks the second major partnership for the AnTenGager platform, following a global deal with UCB for ATG-201 announced in March 2026. K2 Therapeutics intends to leverage its hub-and-spoke model to accelerate these programs toward clinical development.