Fecal Microbiota Transplantation Capsules with Targeted Colonic Versus Gastric Delivery in Recurrent Clostridium difficile Infection: A Comparative Cohort Analysis of High and Lose Dose

Background Fecal microbiota transplantation (FMT) is an effective therapy for recurrent Clostridium. difficile infection (rCDI). FMT capsules have emerged, and it is unknown if delivery location and dose impact efficacy. Methods We compared two cohorts of patients receiving two capsule formulations: gastric release (FMTgr) and targeted colonic release (FMTcr) at two different sites. Cohort A received FMTgr at (1) high dose : 60 capsules and low dose : 30 capsules. Patients in Cohort B received FMTcr at (1) high dose : 30 capsules (2) low dose : 10 capsules. Clinical cure rates and adverse events were monitored through week 8. Paired t-tests were used to compare diversity pre- and post-FMT. Results 51 rCDI patients were enrolled. Cohort A contained n = 20 and Cohort B contained n = 31. Overall cure at week 8 for FMTgr was 75% (15/20) compared to 80.6% for FMTcr, (25/31), p = 0.63. Both formulations were safe with no serious adverse events. FMTcr was superior at increasing gut microbial diversity. Discussion To our knowledge, this is the first study to compare targeted delivery of FMT capsules. While both capsules were safe and efficacious, microbial engraftment patterns were superior in FMTcr.