Here's an example of it taking almost a year:

Capnia Applies for Orphan Drug Designation in the U.S. for the Treatment of Trigeminal Neuralgia
Jan 08, 2015, 07:00 ET from Capnia, Inc.

http://www.prnewswire.com/news-releases/capni...17698.html


Capnia Granted Orphan Designation for Nasal CO2 for the Treatment of Trigeminal Neuralgia
REDWOOD CITY, Calif., Dec. 21, 2015
http://investors.capnia.com/phoenix.zhtml?c=2...ID=2124295