The terms, per the grant. On March 1, 2022, Daiichi Sankyo was issued US11261261B2, "Method of treating cancer comprising administration of anti-HER2 antibody-drug conjugate." The CPC stack — C07K 16/32 (anti-HER2 antibody), A61K 47/6803/6849/6851/6855 (the linker-payload conjugation series), plus the C07D 491/22 payload chemistry — describes the full ADC: antibody, linker, and cytotoxic payload.
Why ADC IP commands premium deals: an antibody-drug conjugate is a three-part invention — targeting antibody, cleavable linker, cytotoxic payload — and each part is separately protectable. That layered IP, plus the demonstrated clinical value of HER2-directed conjugates, is why this class has anchored multi-billion-dollar upfronts and milestone-laden collaborations.
The structure point: when a deal is built on an ADC, the value sits across the antibody, the linker-payload chemistry, and the method-of-treatment claims. For a model, that means the royalty base can be broad and the freedom-to-operate analysis has to clear all three layers. Naming the grant is how you see which layers a deal actually controls.
What the grant does not promise: it does not guarantee a specific clinical result, an approval in any given indication, or freedom from competing antibody and linker estates. It is an exclusivity claim on a method using a defined conjugate — a real asset within a crowded class.
The takeaway: when an ADC deal crosses the desk, read the antibody, linker, and method claims as three assets, not one. Daiichi Sankyo's March 2022 HER2-ADC grant is a dated, concrete example of the layered IP that the biggest oncology deals are written around.