Sarah Mische PhD, Robert Orenstein DO, Erik R. Dubberke MD, Sahil Khanna MBBS, Gail Hecht MD, Herbert Dupont MD, Christine H. Lee MD, Dale N. Gerding MD, Ken Blount PhD
- Effective treatment options for recurrent C. difficile infection (rCDI) are limited.
- High recurrence rates are associated with current standard-of-care antibiotic therapy.
- Microbiota-based therapies are being developed and evaluated in clinical studies.
- RBX2660 has shown efficacy in preventing rCDI at 8 weeks in a randomized, blinded, placebo-controlled Phase 2B trial (PUNCH CD2; NCT02299570).
- Here we report RBX2660 durability beyond the initial primary clinical end-point of a subsequent Phase 2 openlabel study (NCT02589847), demonstrating rCDI prevention at 6 months post-treatment.
Clinical Trial Design
- Inclusion criteria: >18 years old with documentation of either 2 recurrences after a primary episode and had completed at least two rounds of standard-of-care oral antibiotic therapy, or at least 2 episodes of severe CDI resulting in hospitalization; a positive stool test for the presence of toxigenic C. difficile within 60 days prior to enrollment.
- Antibiotics were discontinued 24-48 hours prior to the first enema.
- Safety was assessed in clinic at 1, 4, and 8 weeks and via telephone at 2, 3, between 5-7 weeks, and at 3, 6, 12 and 24 months.
- Success was defined as the absence of CDI at 8 weeks following completion of last treatment. Subjects were classified as treatment failures if all 4 criteria were met (recurrence of diarrhea <8 weeks after delivery of treatment, positive laboratory C. difficile diagnosis, requirement of retreatment and no other cause for diarrhea).
- See poster (2.5 MB)
- See poster (2.5 MB)
6 month follow-up
- 6-month efficacy data collected for 117 of 119 patients who had successful response to RBX2660 at 8-weeks post-treatment
- 8 exits due to non-CDI reasons: Lost to follow-up, death
- 3 patients reported CDI recurrence
- 97.2% of subjects who had successful outcome at 8 weeks remained CDI-free at 6 months post-RBX2660
- RBX2660 was efficacious for the prevention of rCDI with long-term durability at 6 months post-treatment.
- This result is consistent with 6 month rCDI prevention reported for the Phase 2B PUNCH CD2 study.
- Long-term follow-up of RBX2660 safety and efficacy 24 months is ongoing.