Marcio Souza has served as a director and President and Chief Executive Officer since April 2020. Prior to joining Praxis, Mr. Souza was at PTC Therapeutics, Inc., or PTC, where he served as its Chief Operating Officer from May 2017 to April 2020 and its Senior Vice President and Head of Product Strategy from July 2016 to May 2017. Prior to joining PTC, Mr. Souza served in positions of increasing responsibility at NPS Pharmaceuticals, Inc., Shire Human Genetic Therapies Inc. and Sanofi Genzyme Corporation. Mr. Souza has served on the board of directors of Aeglea BioTherapeutics, Inc. since June 2021. From May 2019 to May 2020, Mr. Souza also served on the board of directors of Clearpoint Neuro, Inc. (previously MRI Interventions, Inc.). Mr. Souza received a degree in pharmacy and biochemistry with a specialization in toxicology and clinical analysis from the University of São Paulo and an M.B.A. from Fundação Dom Cabral.