Genentech entered a multi-stage deal with DualityBio to advance antibody-drug conjugates designed for resistance to topoisomerase inhibitor payloads. Under the agreement, DualityBio receives $45 million upfront, with total milestone payments potentially exceeding $1 billion plus tiered royalties, as Genentech takes over later-stage development and commercialization. DualityBio will conduct discovery work and early-stage global clinical development through Phase I trials, while Genentech will continue development under a global license. The collaboration centers on DualityBio’s DUPAC platform, which is designed to produce next-generation payloads aimed at overcoming resistance to older topo-1 inhibitor–based ADCs. The strategic signal is clear: both companies are positioning for ADC expansion into earlier lines and for patients who progress on existing modalities, where payload resistance is increasingly viewed as a bottleneck.