My Confusion about Postmarket Requirements & Study Commitments

FDA has a database of postmarket requirements and study commitments (translation: "we're going to approve your drugs, but you have to promise to run these additional trials after we approve").

This database is updated quarterly and FDA even provides its own search engine to mine this database.

I've only been indexing their collection of data for a couple of quarters, but with the most recent update (April 30), I noticed something that I hadn't realized before.

Specifically, each new quarter's data *wipes out* the previous quarter's data. For example, the January 31 update contained 3381 postmarket requirements that could be searched via FDA.

In contrast, the April 30 data release contains only 1910 requirements. So, it looks like the FDA removes commitments that have been satisfied (I'm not 100% sure about the precise commitments that are removed each quarter, but this seems like the most reasonable explanation).

In practice, this means that you can't use FDA's search-engine to get a historical look at the types of commitments/requirements that were mandated by the FDA.

For example, if you search the FDA's postmarket requirements database for Zoladex you get no results. If you search using FDAble, you'll see that Astrazeneca UK had 3 requirements relating to Zoladex that were fulfilled in 2008.

I imagine that this historical information would be useful to many people (clinicians, persons performing competitive intelligence & strategy regarding drug development, etc.).