DENILEUKIN DIFTITOX | B103767 | EISAI INC
No 12-year reference-product exclusivity is listed in the Purple Book, and the reference product was first approved Feb. 5, 1999 — before BPCIA (March 23, 2010), so any 12-year exclusivity has long expired.
Full-label vs. best-skinny biosimilar entry
| Scenario | Date | Status | Controlling |
|---|---|---|---|
| Best-skinny entry (floor) | Open now | Open now | no live licensure floor |
| Full-label entry | Feb. 5, 2006 | Passed | no live block |
Best-skinny equals full-label — no carveable orphan block runs past the licensure floor.
Marketing-entry ceiling (litigation risk)
Patents do not gate FDA licensure of a biosimilar — FDA licenses biosimilars (full or carved label) without adjudicating any patent. These are a practical marketing-entry ceiling resolved in the § 262(l) patent dance and ordinary litigation. A formulation/compound patent caps practical skinny entry via litigation (Regeneron v. Mylan); a method-of-use patent is carveable and gates nothing.
0 formulation/compound (cap skinny entry) · 2 method-of-use (carveable — gate nothing) · 0 device/diagnostic/manufacturing
Disclaimer: Identifying an available carve-out is not a prediction that FDA will approve the particular carved label, nor that marketing it is free of infringement risk. For biologics, availability turns on exclusivities, not patents: FDA licenses a biosimilar (full or carved label) without adjudicating any patent, and patent disputes run through the § 262(l) patent dance and ordinary litigation, outside this availability view.
2 AI-discovered patents, sorted by relevance.
No patent or exclusivity listings for this strength.