The terms, per the grant. On May 10, 2022, Seagen was issued US11325980B2, "Combination therapy using a LIV1-ADC and a chemotherapeutic." The CPC stack — C07K 16/3015 (the targeting antibody), A61K 47/6803/6811/6851 (conjugation), plus the A61K 31/337/555/704 chemotherapy combinations — claims the conjugate used together with specific chemotherapies.
Why combination claims matter to a deal: a combination-therapy patent protects how a drug is used alongside another agent, which can extend exclusivity and open additional licensing and co-development structures beyond the base composition. For a franchise, combination IP is a way to keep refreshing the protective estate as the core molecule ages.
The structure point: combination grants support add-on deal structures — co-development, label-expansion collaborations, and method-of-use licenses — that layer on top of the composition license. For a model, they are incremental royalty-bearing assets tied to specific clinical uses rather than to the molecule alone.
What the grant does not promise: that the combination is approved, that it outperforms monotherapy, or that it forecloses all competing regimens. It is an exclusivity claim on a specific combination use — valuable, but use-specific.
The takeaway: when valuing a conjugate franchise, read the combination-therapy grants as franchise-extending assets layered on the core ADC. Seagen's May 2022 LIV-1 combination grant is a dated example of how combination claims add deal surface area.