When a biologic's core composition patent is aging, the franchise's remaining exclusivity often lives in method-of-use grants, and US10617755B2 - "Combination therapy for the treatment of glioblastoma," issued April 14, 2020 to Genentech - is a clean example of the type. It claims using an anti-VEGF antibody in a defined combination for a specific cancer.
The first point a careful reader makes: this is a use patent, not a composition patent, so it does not extend the term of the antibody molecule itself. What it does is protect a particular therapeutic application. A competitor free of the composition claim may still face this grant if it markets the same combination for the same indication.
That layering is how franchises stretch effective exclusivity past the headline expiry of the molecule. The CPC tags here - A61K 39/3955 (antibody medicinal preparations), A61K 45/06 (combinations), C07K 16/22 (anti-VEGF antibody) - describe a combination-of-actives claim, the kind that accumulates around a durable biologic over a decade.
The litigation-relevant caveat, in editorial discipline, is that an allegation of infringing a use patent is not a holding, and the scope of a combination claim is exactly what gets contested. Whether a competitor's regimen reads on the claimed combination turns on the specific partners and the indication, not on the franchise name. None of that is decided until a court construes the claim.
For exclusivity math, the practical takeaway is to never read a biologic's protection off a single composition-patent expiry date. The effective runway is the envelope of composition plus formulation plus use grants, and combination patents like this one are a recurring way that envelope extends beyond what the molecule patent alone would suggest.