Challenges recruiting to a proof-of-concept pharmaceutical trial for a rare disease: the trigeminal neuralgia experience oleh Joanna M. Zakrzewska, Joanne Palmer, Lars Bendtsen, Giulia Di Stefano, Dominik A. Ettlin, Stine Maarbjerg, Mark Obermann, Valerie Morisset, Deb Steiner, Simon Tate, Giorgio Cruccu