Use of Darvadstrocel (Allogenic Stem Cell Therapy) for Crohn's Fistulas in Real Clinical Practice: The National Project to Implement Mesenchymal Stem Cell for the Treatment of Perianal Crohn's Fistula (the PRIME Study).

BACKGROUND: Perianal fistulas may affect 15-50% of patients with Crohn's disease. Treatment is complex, requiring a multidisciplinary approach. Darvadstrocel (allogenic mesenchymal cells obtained from lipoaspirates) was approved in 2018 by the European and Spanish Agencies of Medicines and Medical Products as a treatment for fistulas in Crohn's disease. Recent European Crohn's and Colitis Organisation and Spanish Working Group on Crohn's Disease and Ulcerative Colitis guidelines state that darvadstrocel is effective with a favorable safety profile and a strong level of evidence (2). OBJECTIVE: Presenting real-world effectiveness data for darvadstrocel in a Spanish population. DESIGN: Observational retrospective cohort study with prospective data gathering. SETTINGS: Fourteen institutions. PATIENTS: From November 2019-April 2022, all patients (73) treated with darvadstrocel in these institutions were included, fulfilling the following criteria: 1) complex fistula/s in a patient with Crohn's disease; 2) failure of conventional and antitumor necrosis factor treatment; 3) absence of collections >2 cm confirmed by pelvic MRI scan at the time of surgery. INTERVENTIONS: Darvadstrocel treatment. MAIN OUTCOME MEASURES: Clinical response (closure of ≥50% of external openings), complete clinical closure (100% of external openings) and radiological closure (no fluid collection >2 cm, no edema or inflammation) evaluated 6 months after treatment. RESULTS: Clinical response was observed in 63 patients (86.3%), complete clinical closure in 50 patients (68.5%) and radiological closure in 45 patients (69.2%). Combined clinical and radiological response was observed in 41 patients (63.1%). Not all clinically healed patients had radiological closure and vice versa. No serious adverse events were reported. LIMITATIONS: Retrospective. CONCLUSIONS: Study results were consistent with those reported in previous clinical trials, real-world efficacy findings from the INSPIRE study (assessing darvadstrocel effectiveness in Europe, Israel, Switzerland, UK, and Japan) and previously published literature. Darvadstrocel was effective and demonstrated a favorable safety profile when used in normal clinical practice for treatment of fistulas in Crohn's disease. See Video Abstract.

Autologous adipose-derived stem cells for the treatment of complex cryptoglandular perianal fistula: A randomized clinical trial with long-term follow-up.

The aim of this clinical trial (ID Number NCT01803347) was to determine the safety and efficacy of autologous adipose-derived stem cells (ASCs) for treatment of cryptoglandular fistula. This research was conducted following an analysis of the mistakes of a same previous phase III clinical trial. We designed a multicenter, randomized, single-blind clinical trial, recruiting 57 patients. Forty-four patients were categorized as belonging to the intent-to-treat group. Of these, 23 patients received 100 million ASCs plus intralesional fibrin glue (group A) and 21 received intralesional fibrin glue (group B), both after a deeper curettage of tracks and closure of internal openings. Fistula healing was defined as complete re-epithelialization of external openings. Those patients in whom the fistula had not healed after 16 weeks were eligible for retreatment. Patients were evaluated at 1, 4, 16, 36, and 52 weeks and 2 years after treatment. Results were assessed by an evaluator blinded to the type of treatment. After 16 weeks, the healing rate was 30.4% in group A and 42.8% in group B, rising to 55.0% and 63.1%, respectively, at 52 weeks. At the end of the study (2 years after treatment), the healing rate remained at 50.0% in group A and had reduced to 26.3% in group B. The safety of the cellular treatment was confirmed and no impact on fecal continence was detected. The main conclusion was that autologous ASCs for the treatment of cryptoglandular perianal fistula is safe and can favor long-term and sustained fistula healing.

Treatment of Crohn's-Related Rectovaginal Fistula With Allogeneic Expanded-Adipose Derived Stem Cells: A Phase I-IIa Clinical Trial.

: The aim of this clinical trial was to determine the safety and feasibility of expanded allogeneic adipose-derived stem cells to treat Crohn's-related rectovaginal fistula (CRRVF). We designed a phase I-II clinical trial (https://ClinicalTrials.gov, NCT00999115) to treat 10 patients with CRRVF. Patients receiving biological therapy during follow-up were excluded. Curettage was performed, and a vaginal or rectal flap was added if the surgeon considered it necessary. The therapeutic protocol included intralesional injection of 20 million stem cells in the vaginal walls (submucosal area) and fistula tract. Healing was evaluated 12 weeks later. If the fistula had not healed, a second dose of 40 million stem cells was administered. Patient follow-up was 52 weeks from last cell injection. Healing was defined as re-epithelialization of both vaginal and rectal sides and absence of vaginal drainage. Cytokines and immunological blood tests were monitored. Serious adverse events or rejection issues were not observed. Five patients were excluded because biologic drugs were required to treat a Crohn's disease flare-up during follow-up. Cytokine profiles and immunotoxicity assays showed no statistically significant alterations. Sixty percent of the nonexcluded patients achieved a complete healing. Expanded allogeneic adipose-derived stem-cell injection is a safe and feasible therapy for treating CRRVF, and the healing success rate seems promising (60%). The results of this trial encourage further exploration into this therapy. SIGNIFICANCE: This may be the first publication in which allogeneic stem cells to treat rectovaginal fistula in Crohn´s disease seem to be a feasible and safe treatment. Additional studies are necessary to confirm the efficacy profile of the allogeneic stem cells strategy in a controlled design.

First-in-Human Case Study: Pregnancy in Women With Crohn's Perianal Fistula Treated With Adipose-Derived Stem Cells: A Safety Study.

UNLABELLED: The aim of this study was to determine whether treatment with adipose-derived stem cells (ASCs) had any influence on fertility, course of pregnancy, newborn weight, or physical condition of newborns. We performed a retrospective study of patients with a desire to become pregnant after having received intralesional injection of autologous ASCs for the treatment of perianal or rectovaginal fistula associated with Crohn's disease. We collected data on the resulting pregnancies, deliveries, and newborns of these patients. ASCs were expanded in vitro and characterized according to the international guidelines for cell surface markers (clusters of differentiation) and differentiated to adipocytes, chondrocytes, and osteocytes prior to implantation (except first implant in 2002). We analyzed five young women with Crohn's disease treated with ASCs: one for rectovaginal and perianal fistula, two for rectovaginal fistula only, and two for perianal fistula only. All patients received 2 doses of 20 million and 40 million cells at an interval of 3-4 months. Another patient received 2 doses of 6.6 million and 20 million ASCs with 9 months between each dose. Fertility and pregnancy outcomes were not affected by cell therapy treatment. No signs of treatment-related malformations were observed in the neonates by their respective pediatricians. In the patients studied, cell therapy with ASCs did not affect the course of pregnancy or newborn development. SIGNIFICANCE: Local treatment with mesenchymal stem cells derived from adipose tissue seems not to affect the ability to conceive, the course of pregnancy, pregnancy outcomes, or newborns' health in female patients. This is the first publication about pregnancy outcome in women with perianal fistula and Crohn's disease treated with stem cell therapy, and could be of interest for doctors working in cell therapy. This is a very important question for patients, and there was no answer for them until now.

Recurrent anal fistulae: limited surgery supported by stem cells.

AIM: To study the results of stem-cell therapy under a Compassionate-use Program for patients with recurrent anal fistulae. METHODS: Under controlled circumstances, and approved by European and Spanish laws, a Compassionate-use Program allows the use of stem-cell therapy for patients with very complex anal fistulae. Candidates had previously undergone multiple surgical interventions that had failed to resolve the fistulae, and presented symptomatic recurrence. The intervention consisted of limited surgery (with closure of the internal opening), followed by local implant of stem cells in the fistula-tract wall. Autologous expanded adipose-derived stem cells were the main cell type selected for implant. The first evaluation was performed on the 8(th) postoperative week; outcome was classified as response or partial response. Evaluation one year after the intervention confirmed if complete healing of the fistula was achieved. RESULTS: Ten patients (8 male) with highly recurrent and complex fistulae were treated (mean age: 49 years, range: 28-76 years). Seven cases were non-Crohn's fistulae, and three were Crohn's-associated fistulae. Previous surgical attempts ranged from 3 to 12. Two patients presented with preoperative incontinence (Wexner scores of 12 and 13 points). After the intervention, six patients showed clinical response on the 8(th) postoperative week, with a complete cessation of suppuration from the fistula. Three patients presented a partial response, with an evident decrease in suppuration. A year later, six patients (60%) remained healed, with complete reepithelization of the external opening. Postoperative Wexner Scores were 0 in six cases. The two patients with previous incontinence improved their scores from 12 to 8 points and from 13 to 5 points. No adverse reactions or complications related to stem-cell therapy were reported during the study period. CONCLUSION: Stem cells are safe and useful for treating anal fistulae. Healing can be achieved in severe cases, sparing fecal incontinence risk, and improving previous scoring.

The concentration of deoxyribonucleic acid in plasma from 73 patients with colorectal cancer and apparent clinical correlations.

BACKGROUND: Detection of cell-free plasma DNA has considerable potential as a tool for the diagnosis and assessment of the prognosis of many types of cancer. The aim of the present study was to quantify, by spectrophotometry, the cell-free DNA in plasma samples from patients with colorectal cancer at different stages of the disease and to attempt to correlate the resultant values with the clinical picture. METHODS: We reviewed the medical reports of 73 patients, who had undergone resection of primary colorectal cancer. Samples of blood had been taken from each patient immediately prior to surgery. DNA was extracted from samples of plasma and quantified, by spectrophotometry, after a storage period of no longer than 2 years in 89% of the cases examined. RESULTS: The mean(+/-S.D.) concentration of DNA in plasma samples was 108+/-156 ng/microl. We found a statistically significant correlation between the concentration of DNA and the presence of metastases (mainly liver metastases). CONCLUSION: The detection and quantitation of cell-free DNA in plasma, using this simple technique, might be of clinical value for the surveillance of colon cancer patients and the detection of metastases.