Anavex Life Sciences Corp (AVXL)

[Doc328]

A pivotal study is an adequate well controlled trial used to demonstrate efficacy and safety to support the NDA or other regulatory submission. In general these are phase 3 studies. The FDA often uses the term 'adequate well controlled study' rather than phase 3 since some phase 2's can be considered AWCs. The standard has been two pivotal trials needed for approval.

There are of course exceptions. Oncology and orphan drugs are often approved with a single trial (AVXL could use the Excellence Rett trial for Rett approval with one AWC trial). AD is not an oncology or orphan indication.

This is an interesting article that goes into far more detail. Of the examples, 3 are neurology drugs -- 2 MS and 1 stroke. The two MS drugs are considered new chemical entities by the regulatory agency but are highly related to drugs already on the market (Plegridy is PEGylated Avonex giving it a longer half-life for fewer shots). Teriflunomide (Aubagio) is the major metabolite of leflunomide (Arava) which was already on the market for RA. Interestingly, teriflunomide did 2 successful Phase 3 trials but the second one was not needed and completed while the drug was at the FDA. Being strongly related to an existing marketed drug lowers the bar for safety.