Today, the FDA posted MaPP 5220.2 (here), which outlines a little-known process (because it so seldom happens) that describes how the Agency will go about converting an ANDA approval to a tentative approval (TA). The issue only occurs when a patent challenge is won by the innovator after the expiration of the thirty-month stay and where the Agency has approved the application based on the expiration of the thirty-month stay since the application had otherwise met all approval requirements.
To refresh your memory, a MaPP is a document that is created to “map” (outline) internal FDA policies and procedures. In my time (and a long time that is! Think I started right after work on the coliseum in Rome was originally completed) working in the regulated industry, I can remember this only occurring a handful of times in the thousands of ANDA approvals since the passage of Hatch-Waxman in 1984. The document also outlines in detail the unusual circumstances under which this unicorn can occur, spells out the timing of ANDA approvals based on patent certifications, the patent notification process, and the documentation of the patent response process from industry to the OGD, as well as the general timing of ANDA approval after patent certification and the expiration of the thirty-month stay.
The unique circumstances are brought to bare if an ANDA is approved and then, post-approval, the NDA holder or patent-holder subject of the PIV certification wins a judgement of infringement. Many patent cases run thirty-six months or more, and then there can always be appeals. This document is a good read, even if just to refresh your knowledge of the patent-certification process, and, specifically, if you have never seen the circumstances under which this situation occurs.