Efficacy and safety of fecal microbiota transplantation by washed preparation in patients with moderate to severely active ulcerative colitis

Objective We aimed to evaluate the short‐term efficacy and safety of fecal microbiota transplantation (FMT) by washed preparation for moderate to severely active UC. Methods An open‐label prospective trial was conducted in an inflammatory bowel disease (IBD) tertiary referral center from April 2016 to March 2018. Patients with moderate to severely active UC were randomly assigned to undergo FMT thrice on day 1, 3 and 5 by nasojejunal tube (NJT) or transendoscopic enteral tubing (TET). The primary end‐point was a clinical response at week 2 post‐FMT. The secondary end‐points were clinical and endoscopic remission at week 12 post‐FMT, safety and disease progression. Results Of the nine patients included, 77.8% (7/9) achieved a clinical response at week 2. And 55.6% (5/9) and 33.3% (3/9), respectively, achieved clinical remission and endoscopic remission at week 12. In two patients who had no response to FMT, one switched to anti‐tumor necrosis factor‐α therapy, and the other underwent a colectomy. FMT was delivered through NJT in 44.4% (4/9) of the patients, while TET was used in 55.6% (5/9). The clinical outcomes did not differ significantly based on the delivery route (P > 0.05). Adverse events, all mild and self‐limiting, were observed in 33.3% (3/9) of the patients. Conclusions FMT by washed preparation appears to be a safe and effective adjunct therapy for moderate to severely active UC during a short‐term follow‐up. The efficacy did not differ significantly between the NJT or TET delivery routes. Further randomized controlled studies are needed to confirm these findings.


| INTRODUCTION
Fecal microbiota transplantation (FMT) is very efficacious for the treatment of recurrent Clostridium difficile (C. difficile) infection, with the ability to restore a healthy microbial ecology and a mean cure rate of 87%-90%. 1,2 In 2013, FMT has been suggested by the guidelines in the United States for the clinical treatment of C. difficile infection. 3 However, the efficacy of FMT for treating ulcerative colitis (UC) remains controversial. The etiopathogenesis of UC is thought to be multifactorial, and alterations in the intestinal microbiome are one of its main characteristics. Moreover, there is more resistance to the reversal of enteric microbiota alterations in UC than in C. difficile infection.
In recent years, several randomized placebo-controlled trials (RCTs) have evaluated the efficacy and safety of FMT for treating patients with mild to moderately active UC. In 2015 two clinical RCTs investigating the role of FMT in treating UC were published, but they reported conflicting outcomes. The first study 4 including 75 patients administered weekly enemas for 6 weeks and reported clinical remission rates of 24% in the FMT group compared with 5% in the placebo control group at week 7. The second study 5 including 50 patients which delivered FMT via a nasoduodenal tube at week 0 and week 3 found no significant difference in the achievement of clinical remission between participants who received fecal transplants from healthy donors and those who received autologous stool. Differences in patient populations, dosing regimens and delivery modalities may account for these conflicting results. In 2017 another RCT which administered FMT via a colonoscopy infusion once, followed by enemas 5 days per week for 8 weeks, the steroid-free clinical and endoscopic remission or response rate was 27% in the FMT group compared with 8% in the placebo group (P = 0.021). 6 In 2018 an RCT was published as an abstract using FMT delivered by colonoscopy followed by daily FMT capsules. 7 It used rationally selected donors with high stool butyrate and found that histological inflammation decreased in 4/6 (66.7%) participants in the FMT arm compared with 1/6 (16.6%) in the placebo arm at week 12. In 2019, an RCT was published (N = 73) in which FMT was administered (using anaerobically prepared stool) via a colonoscopy followed by two enemas over 7 days. The steroid-free remission rate was 32% in the group that received pooled donor FMT compared with 9% in the group that received autologous FMT (P = 0.03). 8 Taken together, the evidence supports guarded optimism over FMT as a treatment option for UC. However, all these studies enrolled patients with mild to moderately active UC. There have been few studies designed to assess the efficacy and safety of FMT in patients with moderate to severely active UC. In addition, previous studies prepared fecal microbiota primarily by manual methods. However, this method has safety risks and presents challenges with regard to the psychological endurance and level of treatment acceptance of doctors, patients and donors. A washed preparation avoids these defects.
Population-based studies have shown that a washed preparation can significantly reduce FMT-related adverse events. 9 Therefore, we have prepared feces with a washed preparation using the automatic purification machine GenFMTer (FMT Medical, Nanjing, Jiangsu Province, China) since April 2016. Therefore, we aimed to assess the short-term efficacy and safety of FMT by a washed preparation in patients with moderate to severely active UC. All patients were randomly assigned to receive FMT via a nasojejunal tube (NJT) or transendoscopic enteral tubing (TET) and were followed up for 12 weeks.  However, we did not allow rectal therapies, including corticosteroids or 5-aminosalicylate during the study.

| Patient selection
The following laboratory examinations were offered to the eligi-

| Donor selection
The study donors were all healthy, unrelated adults. Donors were regarded as standard donors when their fecal microbiota analysis was relatively stable over seven consecutive tests. Each patient was assigned to a single FMT donor.
The donors were carefully screened, and the exclusion criteria

| Fecal microbiota transplantation
We have been preparing the fecal microbiota with a washed preparation since April 2016. This process, recently named washed microbiota transplantation, 11 was originally designed using an automatic microfiltration machine (GenFMTer) and subsequent repeated centrifugation plus suspension, with support from specific facilities. This washing preparation makes it possible to deliver a precise dose of the enriched microbiota instead of relying on the weight of stool. We followed the 1-h FMT protocol, which means that the time from the collection of the stool from the donor to the transplantation of the microbiota into the patient's intestine is less than 1 hour.
All patients meeting the enrollment criteria underwent a standard polyethylene glycol-based bowel preparation on the day prior to the FMT. No antibiotic pretreatment was administered before the FMT. There were two different delivery routes used for transplantation in this study, and the route was selected randomly by using a computer-generated random number table. A NJT was fixed to the jejunum under gastroscopic guidance, and the location was confirmed by X-ray examination. TET was fixed to the cecum with clips under colonoscopic guidance. The purified fecal microbiota was delivered to the intestine via NJT or TET.
Approximately 200-250 mL of fresh fecal suspension was injected over the course of more than 1 minute to avoid abdominal discomfort. The patient was required to remain in the right lateral position for 30 minutes after the FMT. Each patient received FMT thrice on days 1, 3 and 5.

| Outcome measures
Patients were followed up until 12 weeks after the final FMT. The primary end-point was the clinical response at 2 weeks after the FMT, defined as a reduction in the Mayo score of ≥3 and ≥30% from baseline, with a decrease in the rectal bleeding subscore of ≥1 or a subscore ≤1. The secondary end-points were clinical remission (Mayo score ≤2, with no subscore >1) at week 12 post-FMT, endoscopic remission (Mayo score = 0) at week 12 post-FMT, safety and disease progression (measured by the initiation of anti-TNF-α treatment or switching to a colectomy). In this study, safety was evaluated by assessing the adverse events that occurred within 24 hours of the FMT and then weekly until week 12 post-FMT. The severity of adverse events and the degree to which the event was related to the treatment were graded using U.S. National Cancer Institute criteria. 12

| Statistical analysis
Statistical analysis was performed using SPSS software 26.0 (IBM, Armonk, NY, USA). Descriptive statistics are described as the mean ± standard deviation or median and range, whereas categorical variables are expressed as numbers and percentages. Differences in baseline descriptive variables were assessed using the independent t-test. We assessed categorical data using the χ 2 test and Fisher's exact test. A twosided P value of less than 0.05 was regarded as statistically significant.

| Study enrollment and patients' characteristics
A total of nine patients were included in the study whose median age at  Table 1.    Tables 2 and 3.

| Clinical outcomes of FMT
We then compared the clinical outcomes between patients who received the FMT via different delivery routes, that is, TET or NJT.
There were no significant differences between the two groups in    Furthermore, we prepared the fecal microbiota with a washed preparation using an automatic microfiltration machine. This method avoids the discomfort experienced by doctors and patients during the process of preparing and infusing the fecal microbiota and simultaneously decreased the incidence of adverse events due to FMT. In a previous study it was shown that the rate of adverse events in patients undergoing FMT prepared manually was 21.7%, which was significantly higher than the 8.7% in those who underwent FMT prepared with a washed preparation. 20 In our study, FMT by washed preparation was well tolerated. The overall incidence of adverse events was 33.3% (3/9), and all adverse events were mild and self-limiting, including abdominal pain, diarrhea and fatigue. Although serious events including aspiration, infection and IBD flares have been previously reported, 2,21,22 we did not observe any serious adverse events or infectious complications directly related to FMT.

| Adverse events
Our study had some limitations. First, the sample size was too small to draw a solid conclusion about the effects of FMT on patients with moderate to severely active UC. Second, because it was relatively difficult to obtain written informed consent from severely active patients with UC if there was a possibility of being assigned to the placebo group, a placebo control group was not included in our study.
Finally, the levels of noninvasive biomarkers such as calprotectin were not determined in all patients.
In conclusion, our study used a washed preparation to prepare the fecal microbiota and analyzed the efficacy and safety of FMT for the treatment of moderate to severely active UC, showing that there was a high short-term response and remission rates after FMT. Notably, FMT may be an effective therapy for the steroid-dependent UC group. Additionally, we compared the clinical outcomes between different delivery routes, NJT and TET, and found no significant differences. All the patients tolerated the treatment well and had no serious adverse events. These data suggest that FMT as an adjunct therapy is safe and effective for patients with moderate to severely active UC. Further randomized controlled trials with large sample sizes are needed to confirm our findings, and longer follow-up will be needed to assess its long-term efficacy and safety.