P.0353 Study protocol: psilocybin as a treatment for anorexia nervosa: a pilot study by Douglass, H, Spriggs, MJ, Park, RJ, Read, T, Danby, JL, De Magalhães, FJC, Alderton, KL, Lafrance, A, Nicholls, DE, Erritzøe, D, Nutt, DJ, Carhart-Harris, RL