Results from a new efficacy and safety analysis of the REGENERATE trial of obeticholic acid for treatment of pre-cirrhotic fibrosis due to non-alcoholic steatohepatitis.

BACKGROUND & AIMS: Obeticholic acid (OCA) is a first-in-class farnesoid X receptor agonist and antifibrotic agent in development for the treatment of pre-cirrhotic liver fibrosis due to non-alcoholic steatohepatitis (NASH). We aimed to validate the original 18-month liver biopsy analysis from the phase III REGENERATE trial of OCA for the treatment of NASH with a consensus panel analysis, provide additional histology data in a larger population, and evaluate safety from >8,000 total patient-years' exposure with nearly 1,000 participants receiving study drug for >4 years. METHODS: Digitized whole-slide images were evaluated independently by panels of three pathologists using the NASH Clinical Research Network scoring system. Primary endpoints were (1) ≥1 stage improvement in fibrosis with no worsening of NASH or (2) NASH resolution with no worsening of fibrosis. Safety was assessed by laboratory values and adverse events. RESULTS: Prespecified efficacy analyses included 931 participants. The proportion of participants achieving a ≥1 stage improvement in fibrosis with no worsening of NASH was 22.4% for OCA 25 mg vs. 9.6% for placebo (p <0.0001). More participants receiving OCA 25 mg vs. placebo achieved NASH resolution with no worsening of fibrosis (6.5% vs. 3.5%, respectively; p = 0.093). Histology data in a larger population of 1,607 participants supported these results. Safety data included 2,477 participants. The incidence of treatment-emergent adverse events (TEAEs), serious TEAEs, and deaths was not substantively different across treatment groups. Pruritus was the most common TEAE. Rates of adjudicated hepatic, renal, and cardiovascular events were low and similar across treatment groups. CONCLUSIONS: These results confirm the antifibrotic effect of OCA 25 mg. OCA was generally well tolerated over long-term dosing. These data support a positive benefit:risk profile in patients with pre-cirrhotic liver fibrosis due to NASH. IMPACT AND IMPLICATIONS: Patients with non-alcoholic steatohepatitis (NASH) often have liver scarring (fibrosis), which causes an increased risk of liver-related illness and death. Preventing progression of fibrosis to cirrhosis or reversing fibrosis are the main goals of drug development for NASH. In this clinical trial of obeticholic acid (OCA) in patients with NASH (REGENERATE), we reaffirmed our previous results demonstrating that OCA was superior to placebo in improving fibrosis using a more rigorous consensus panel analysis of liver biopsies taken at month 18. We also showed that OCA treatment resulted in dose-dependent reductions of serum liver biochemistries and liver stiffness measurements compared with placebo, even in participants in whom histologic fibrosis did not change at 18 months, providing evidence that the benefit of OCA extends beyond what is captured by the ordinal NASH CRN scoring system. OCA was well tolerated with a favorable safety profile supporting a positive benefit: risk profile in patients with pre-cirrhotic liver fibrosis due to NASH.

Obeticholic acid for the treatment of non-alcoholic steatohepatitis: interim analysis from a multicentre, randomised, placebo-controlled phase 3 trial.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a common type of chronic liver disease that can lead to cirrhosis. Obeticholic acid, a farnesoid X receptor agonist, has been shown to improve the histological features of NASH. Here we report results from a planned interim analysis of an ongoing, phase 3 study of obeticholic acid for NASH. METHODS: In this multicentre, randomised, double-blind, placebo-controlled study, adult patients with definite NASH, non-alcoholic fatty liver disease (NAFLD) activity score of at least 4, and fibrosis stages F2-F3, or F1 with at least one accompanying comorbidity, were randomly assigned using an interactive web response system in a 1:1:1 ratio to receive oral placebo, obeticholic acid 10 mg, or obeticholic acid 25 mg daily. Patients were excluded if cirrhosis, other chronic liver disease, elevated alcohol consumption, or confounding conditions were present. The primary endpoints for the month-18 interim analysis were fibrosis improvement (≥1 stage) with no worsening of NASH, or NASH resolution with no worsening of fibrosis, with the study considered successful if either primary endpoint was met. Primary analyses were done by intention to treat, in patients with fibrosis stage F2-F3 who received at least one dose of treatment and reached, or would have reached, the month 18 visit by the prespecified interim analysis cutoff date. The study also evaluated other histological and biochemical markers of NASH and fibrosis, and safety. This study is ongoing, and registered with ClinicalTrials.gov, NCT02548351, and EudraCT, 20150-025601-6. FINDINGS: Between Dec 9, 2015, and Oct 26, 2018, 1968 patients with stage F1-F3 fibrosis were enrolled and received at least one dose of study treatment; 931 patients with stage F2-F3 fibrosis were included in the primary analysis (311 in the placebo group, 312 in the obeticholic acid 10 mg group, and 308 in the obeticholic acid 25 mg group). The fibrosis improvement endpoint was achieved by 37 (12%) patients in the placebo group, 55 (18%) in the obeticholic acid 10 mg group (p=0·045), and 71 (23%) in the obeticholic acid 25 mg group (p=0·0002). The NASH resolution endpoint was not met (25 [8%] patients in the placebo group, 35 [11%] in the obeticholic acid 10 mg group [p=0·18], and 36 [12%] in the obeticholic acid 25 mg group [p=0·13]). In the safety population (1968 patients with fibrosis stages F1-F3), the most common adverse event was pruritus (123 [19%] in the placebo group, 183 [28%] in the obeticholic acid 10 mg group, and 336 [51%] in the obeticholic acid 25 mg group); incidence was generally mild to moderate in severity. The overall safety profile was similar to that in previous studies, and incidence of serious adverse events was similar across treatment groups (75 [11%] patients in the placebo group, 72 [11%] in the obeticholic acid 10 mg group, and 93 [14%] in the obeticholic acid 25 mg group). INTERPRETATION: Obeticholic acid 25 mg significantly improved fibrosis and key components of NASH disease activity among patients with NASH. The results from this planned interim analysis show clinically significant histological improvement that is reasonably likely to predict clinical benefit. This study is ongoing to assess clinical outcomes. FUNDING: Intercept Pharmaceuticals.

Retrospective subgroup analysis of fecal microbiota, live-jslm (REBYOTA®) administered by colonoscopy under enforcement discretion for the prevention of recurrent Clostridioides difficile infection.

Background: Fecal microbiota, live-jslm (RBL; REBYOTA®), is the first Food and Drug Administration (FDA)-approved, single-dose, rectally administered, microbiota-based live biotherapeutic product for preventing Clostridioides difficile infection (CDI) recurrence. Alternative routes of administration are of clinical interest. Objectives: Evaluate the safety and efficacy of RBL administration via colonoscopy. Design: Retrospective analysis of electronic medical records of participants administered RBL via colonoscopy under FDA enforcement discretion. Methods: The number of participants with treatment and/or procedure-emergent adverse events (TEAEs) was evaluated. Treatment success and sustained clinical response, defined as the absence of CDI recurrence within 8 weeks and 6 months, respectively, were evaluated. Results: TEAEs were experienced by 75% (6/8) of participants; most were mild to moderate in severity, and none due to RBL or its administration. Most participants had treatment success (80%; 8/10); 75% (6/8) had sustained clinical response. Conclusion: Real-world safety and efficacy of RBL administered via colonoscopy were consistent with clinical trials of rectally administered RBL.

Retrospective Analysis of the Safety and Efficacy of Fecal Microbiota, Live-jslm (REBYOTATM) Administered Under Enforcement Discretion to Patients With Clostridioides difficile Infection.

Background: Fecal microbiota, live-jslm (RBL; REBYOTA™), the first microbiota-based live biotherapeutic approved by the US Food and Drug Administration to prevent recurrent Clostridioides difficile infection (rCDI) in adults, has been evaluated in 5 prospective clinical trials. A retrospective analysis considered the safety and efficacy of RBL administered under US Food and Drug Administration enforcement discretion to patients with rCDI and broad eligibility criteria mimicking real-world practice. Methods: We retrospectively identified adults with rCDI treated with RBL under enforcement discretion between November 1, 2015, and September 30, 2019, across 5 study sites. CDI diagnosis was based on site-specific practice. The primary safety set (PSS) included all patients who were naïve to previous RBL treatment and had continuously comprehensive medical records for 6 months following treatment. Results: The primary treatment cohort had 94 patients; the PSS included 64 patients with common comorbidities receiving diverse chronic therapeutics. Most treatment-emergent adverse events were mild to moderate in severity and comparable between comorbidity subgroups and the overall population. There were no serious adverse events related to RBL or the administration procedure. In the PSS, 82.8% of RBL-treated patients responded at 8 weeks, of whom 88.7% had sustained response through 6 months. The number of RBL doses administered had no marked effect on outcome. Conclusions: Together with prospective clinical trial outcomes, these findings support the efficacy and safety of RBL to prevent rCDI, with diagnostics and comorbidities representative of real-world clinical practice.

Efficacy and Safety of RBX2660 in PUNCH CD3, a Phase III, Randomized, Double-Blind, Placebo-Controlled Trial with a Bayesian Primary Analysis for the Prevention of Recurrent Clostridioides difficile Infection.

BACKGROUND: Recurrent Clostridioides difficile infection, associated with dysbiosis of gut microbiota, has substantial disease burden in the USA. RBX2660 is a live biotherapeutic product consisting of a broad consortium of microbes prepared from human stool that is under investigation for the reduction of recurrent C. difficile infection. METHODS: A randomized, double-blind, placebo-controlled, phase III study, with a Bayesian primary analysis integrating data from a previous phase IIb study, was conducted. Adults who had one or more C. difficile infection recurrences with a positive stool assay for C. difficile and who were previously treated with standard-of-care antibiotics were randomly assigned 2:1 to receive a subsequent blinded, single-dose enema of RBX2660 or placebo. The primary endpoint was treatment success, defined as the absence of C. difficile infection diarrhea within 8 weeks of study treatment. RESULTS: Of the 320 patients screened, 289 were randomly assigned and 267 received blinded treatment (n = 180, RBX2660; n = 87, placebo). Original model estimates of treatment success were 70.4% versus 58.1% with RBX2660 and placebo, respectively. However, after aligning the data to improve the exchangeability and interpretability of the Bayesian analysis, the model-estimated treatment success rate was 70.6% with RBX2660 versus 57.5% with placebo, with an estimated treatment effect of 13.1% and a posterior probability of superiority of 0.991. More than 90% of the participants who achieved treatment success at 8 weeks had sustained response through 6 months in both the RBX2660 and the placebo groups. Overall, RBX2660 was well tolerated, with manageable adverse events. The incidence of treatment-emergent adverse events was higher in RBX2660 recipients compared with placebo and was mostly driven by a higher incidence of mild gastrointestinal events. CONCLUSIONS: RBX2660 is a safe and effective treatment to reduce recurrent C. difficile infection following standard-of-care antibiotics with a sustained response through 6 months. CLINICAL TRIAL REGISTRATION: NCT03244644; 9 August, 2017.

Clostridioides difficile is a diarrhea-causing bacterium that is associated with potentially serious and fatal consequences. Antibiotics used to treat or prevent infections have a side effect of damaging the healthy protective gut bacteria (microbiota). Damage to the gut microbiota can allow C. difficile to over-grow and produce toxins that injure the colon. Paradoxically, the standard of care treatment of C. difficile infection (CDI) is antibiotics. Although initially effective for the control of diarrhea, antibiotics can leave a patient at risk for CDI recurrence after antibiotic treatment is stopped. Live biotherapeutic products are microbiota-based treatments used to repair the gut microbiota. These products have been shown to reduce the recurrence of CDI. RBX2660 is an investigational microbiota-based live biotherapeutic. RBX2660 contains a diverse set of microorganisms. RBX2660 has been developed to reduce CDI recurrence in adults following antibiotic treatment for recurrent CDI. This study was conducted to demonstrate that RBX2660 is effective and safe in treating patients with recurrent CDI. Treatment was considered successful in participants who did not experience CDI recurrence within 8 weeks after administration. Overall, statistical modeling demonstrated that 70.6% of participants treated with RBX2660 and 57.5% of participants treated with placebo remained free of CDI recurrence through 8 weeks. A 13.1 percentage point increase in treatment success was observed with RBX2660 treatment compared with placebo. In participants who achieved treatment success at 8 weeks, more than 90% remained free of CDI recurrence through 6 months. The most common side effects with RBX2660 treatment were abdominal pain and diarrhea. No serious treatment-related side effects were reported. The current data from the comprehensive clinical development program support a positive benefit-risk profile for RBX2660 in the reduction of CDI recurrence in adults following antibiotic therapy for recurrent CDI.

Diverticular disease-associated segmental colitis.

Diverticular disease-associated segmental colitis is a unique variant of chronic colitis limited to segments of the left colon that harbor diverticula. Histologically, this disease mimics chronic idiopathic inflammatory bowel disease and can be indistinguishable from ulcerative colitis or Crohn's colitis on histologic grounds alone. Patients typically present with hematochezia and cramping abdominal pain, and colonoscopic evaluation reveals inflammatory changes limited to the segment of bowel containing the diverticula, with rectal sparing. Although this disease does not appear to be an unusual form of diverticulitis but possibly an immunologically mediated process, many patients respond to treatment directed toward diverticulitis. A subset of patients requires immunosuppressive therapy and/or surgery, and a small subset progresses to develop classic ulcerative colitis. Because of the histologic overlap with ulcerative colitis and occasionally Crohn's colitis, it is essential that endoscopists provide a full description of the macroscopic appearance of the inflammatory changes at endoscopy, such as limitation to a segment of diverticular disease, so that the pathologist can provide a more informative interpretation of the biopsy.