The Repository of Registered Migraine Trials (RReMIT) database provides a snapshot of registered migraine clinical trials and a scorecard for public availability of results. A description of the RReMIT database is provided in an article published in Neurology (reference below). Links to websites listed in the database may not still be active, and some studies may have had full publication of results since the most recent updating of the database.
The most recent version of the database is available here.
Dufka FL, Dworkin RH, Rowbotham MC. How transparent are migraine clinical trials? Repository of Registered Migraine Trials (RReMIT). Neurology, 2014;83:1372-1381.