D.S. had research contracts with Tufts Medical Center from Prolacta, Summit Therapeutics, Seres Health, and Merck. Consultant to Prolacta and Merck. E.D. is an employee of Summit (Oxford) Ltd. at the time of manuscript submission, and owns stock options in Summit Therapeutics (parent company). K.G. had research funding paid to the University of Houston from Summit Therapeutics, Seres Health, Paratek, and Acuryx Pharmaceuticals. K.C. has research funds paid to her institution from Meridian, BioRad, Qiagen, and Great Basin as well as a consultant fee from B.D. Diagnostics. She serves on the Scientific Advisory Boards of Co-Diagnostics, Inc., Cytovale, Inc., and Pattern Diagnostics, Inc. E.G. is a consultant for Accurx Pharmaceuticals, L.L.C., Merck, Summit Pharmaceuticals P.L.C., Shionogi, Kindred Hospital system, BioK+, and speakers bureaus for Merck and Shionogi. S.J. is a consultant for Accurx, BioK+, Ferring Pharmaceuticals, and Summit Therapeutics. D.G. is a consultant for Destiny Pharma, Plc., and holds a patent for treatment of CDI with a non-toxigenic C. difficile licensed to Destiny Pharma. C.T. has received research funding through grants to Tufts Medical Center from Actelion, Merck, and Summit Therapeutics, Plc. She has served as a consultant to Summit Plc and Delnove. S.W., Q.W., A.S., D.B., L.G., L.M., and C.L. have no conflicts to disclose.