A novel extracellular vesicle paradigm for the treatment of COVID-19 induced acute respiratory distress syndrome (ARDS).

Efficacy of mesenchymal stem cells (MSCs) for treatment of acute respiratory distress syndrome (ARDS) suggests bioactive bone marrow MSC extracellular vesicles (BM-MSC EVs) may be effective. A patient with severe COVID-19 associated ARDS who was presumed to expire was treated with a BM-MSC EV preparation (14 doses over two months) as a rescue treatment for refractory COVID ARDS. Near complete reversal of lung inflammation and fibrosis (per computed tomography), near complete restoration of mobility, hospital discharge (3 months) with resumption of normal activities of daily living (one year) and return to work occurred. No adverse events occurred despite repeated dosing of investigational product, highlighting safety of this potential therapy for ARDS.

Perianal fistulising Crohn's disease: utilising the TOpClass classification in clinical practice to provide targeted individualised care.

BACKGROUND AND AIMS: Perianal fistulation is a challenging phenotype of Crohn's disease with significant impact on quality of life. Historically, fistulae have been classified anatomically in relation to the sphincter complex, and management guidelines have been generalised, with lack of attention to the clinical heterogenicity seen. The recent 'TOpClass classification system' for perianal fistulising Crohn's disease (PFCD) addresses this issue, and classifies patients into defined groups, which provide a focus for fistula management that aligns with disease characteristics and patient goals. In this article, we discuss the clinical applicability of the TOpClass model and provide direction on its use in clinical practice. METHODS: An international group of perianal clinicians participated in an expert consensus to define how the TOpClass system can be incorporated into real-life practice. This included gastroenterologists, IBD surgeons, and radiologists specialised in PFCD. The process was informed by the multi-disciplinary team management of eight high-volume fistula centres in North America, Europe, and Australia. RESULTS: The process produced position statements to accompany the classification system and guide PFCD management. The statements range from the management of patients with quiescent perianal disease to those with severe PFCD requiring diverting-ostomy and/or proctectomy. The optimisation of medical therapies, as well as the use of surgery, in fistula closure and symptom management is explored across each classification group. CONCLUSION: This article provides an overview of the system's use in clinical practice. It aims to enable clinicians to have a pragmatic and patient-goal centred approach to medical and surgical management options for individual patients with PFCD.

Stem Cells and Stem Cell-Derived Factors for the Treatment of Inflammatory Bowel Disease with a Particular Focus on Perianal Fistulizing Disease: A Minireview on Future Perspectives.

Inflammatory bowel disease remains a difficult disease to effectively treat, especially fistulizing Crohn's disease. Perianal fistulas in the setting of Crohn's disease remain an area of unmet need with significant morbidity in this patient population. Up to one third of Crohn's patients will have perianal fistulizing disease and current medical and surgical interventions are of limited efficacy. Thus, most patients experience significant morbidity, narcotic use, and loss of employment and end up with multiple surgical interventions. Mesenchymal stem cells (MSCs) have shown efficacy in phase 3 clinical trials, but considerable infrastructure challenges make MSCs limited with regard to scalability in clinical practice. Extracellular vesicles, being derived from MSCs and capturing the secretome functionality of MSCs, offer similar physiological utility regarding mechanism, while also providing an off the shelf regenerative medicine product that could be widely used in daily clinical practice.

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus.

BACKGROUND & AIMS: Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium. METHODS: We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach. RESULTS: Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers. CONCLUSIONS: Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

Patient engagement and satisfaction with early phase cell therapy clinical trials at a tertiary inflammatory bowel disease center.

Several clinical trials are underway investigating cell and gene therapy, and while these trials are meant to significantly impact patient care, they rely on patient engagement and participation. Unfortunately, clinical trials generally require extensive commitment by subjects. While several studies are using validated surveys to measure patient-reported outcomes, there is a lack of characterization of the patient experience as a subject in these trials. As such, we surveyed mesenchymal stromal cell (MSC) trial participants to understand their perspective. We found that there exists a reliance on one's gastroenterologist and colorectal surgeons for trial introduction and that time and cost were the main barriers to participation. Overall, participants demonstrated high satisfaction with MSC trial participation, but future protocols could incorporate increased use of virtual appointments to optimize patient experience.

Mesenchymal Stem Cell Extracellular Vesicles as a New Treatment Paradigm in Solid Abdominal Organ Transplantation: A Case Series.

Solid abdominal organ transplantation is fraught with variable rates of rejection and graft versus host disease (GVHD). We sought to determine the safety and efficacy of an advanced extracellular vesicle (EV) investigational product (IP) derived from mesenchymal stem cells (MSC) in the transplant patient population. Seven separate emergency investigational new drug (eNIDs) were filed with the Food and Drug Administration (FDA) for the emergency treatment of rejection of an isolated intestinal graft (n = 2), liver allograft graft (n = 2), modified multivisceral graft (n = 3), and GVHD in isolated intestinal transplant patients (n = 2). Fifteen milliliters of IP was administered intravenously on Day 0, 2, 4, and this treatment cycle was repeated up to four times in each patient depending on the treatment protocol allowed by the FDA. Safety (adverse event reporting) and efficacy (clinical status, serologies, and histopathology) were evaluated. There were no adverse events related to IP. All patients had improvement in clinical symptoms within 24 h, improved serologic laboratory evaluation, improved pulmonary symptoms and dermatologic manifestations of GVHD, and complete histologic resolution of graft inflammation/rejection within 7 days of IP administration. Systemic use of a MSC-derived EV IP was successful in achieving histological clearance of intestinal, liver, and multivisceral graft inflammation, and skin and pulmonary manifestations of GVHD.

Safety of bone marrow derived mesenchymal stem cell extracellular vesicle injection for lumbar facet joint pain.

Aim: A 3-month pilot study to evaluate the safety of injecting a bone marrow-derived mesenchymal stem cell extracellular vesicle advanced investigational product (IP) into the lumbar facet joint space as a treatment for chronic low back pain. Methods: 20 healthy adults were treated with IP injections (0.5 ml/joint) and evaluated by three functional assessments 1, 3, 7, 14, 30, 60 and 90 days later. Results: No adverse effects or complications occurred across the 3-month follow-up. There were no reports of worsening pain. After 3 months group average scores improved significantly (p < 0.0001) in the Severity Index (65.04%), Interference Index (72.09%) and Oswestry Disability Index (58.43%) assessments. Conclusion: IP injections were safe and associated with significant functional improvements.

What is this article about? Bone marrow mesenchymal stem cell derived extracellular vesicles (BM-MSC EV), a novel biologic therapeutic candidate, are a safe and promising therapeutic intervention for patients with lumbar facet joint pain, a malady that manifests as persistent low back pain (LBP). 20 adult subjects with lumbar facet joint pain received a single injection of BM-MSC EV investigational product in the lumbar facet joint space. What were the results? Follow-up was conducted through in-office and virtual visits that included outcome measures to determine the safety and efficacy of this therapy. By the 3-month end point, follow-up was successful, and no complications or adverse events were noted. Significant improvements in all three assessments of pain and disability occurred throughout the study. What do the results of the study mean? The results are promising and suggest that BM-MSC EV may represent a revolutionary treatment option with durable efficacy and minimal safety risks. Randomized, controlled clinical studies into the application of BM-MSC EV in lumbar facet joint pain should be pursued to confirm the potential benefits of this novel intervention.

Tofacitinib Is Associated With Increased Risk of Postoperative Venous Thromboembolism in Patients With Ulcerative Colitis.

BACKGROUND: In 2019, the Food and Drug Administration issued a black box warning for increased risk of venous thromboembolism in patients with rheumatoid arthritis exposed to tofacitinib. There are limited data regarding postoperative venous thromboembolism risk in patients with ulcerative colitis exposed to tofacitinib. OBJECTIVE: To assess whether preoperative exposure to tofacitinib is associated with increased odds of postoperative venous thromboembolism. DESIGN: Retrospective review. SETTINGS: Tertiary academic medical center. PATIENTS: Consecutive patients exposed to tofacitinib within 4 weeks before total abdominal colectomy or total proctocolectomy, with or without ileostomy, from 2014 to 2021, matched 1:2 for tofacitinib exposure or no exposure. INTERVENTION: Tofacitinib exposure versus no exposure. MAIN OUTCOME MEASURES: Ninety-day postoperative venous thromboembolism rate. RESULTS: Forty-two patients with tofacitinib exposure and 84 case-matched patients without tofacitinib exposure underwent surgery for medically refractory ulcerative colitis. Nine (22.0%) tofacitinib-exposed patients and 7 (8.5%) unexposed patients were diagnosed with venous thromboembolism within 90 days of surgery. In univariate logistic regression, patients exposed to tofacitinib had 3.01 times increased odds of developing venous thromboembolism within 90 days after surgery compared to unexposed patients ( p = 0.04; 95% CI, 1.03-8.79). Other venous thromboembolism risk factors were not significantly associated with venous thromboembolisms. Venous thromboembolisms in both groups were most commonly portomesenteric vein thromboses (66.7% in the tofacitinib-exposed group and 42.9% in the unexposed group) and were diagnosed at a mean of 23.2 days (range, 3-90 days) postoperatively in the tofacitinib-exposed group and 7.9 days (1-19 days) in the unexposed group. There were no statistically significant differences in location or timing between the 2 groups. LIMITATIONS: Retrospective nature of the study and associated biases. Reliance on clinically diagnosed venous thromboembolisms may underreport the true incidence rate. CONCLUSIONS: Tofacitinib exposure before surgery for medically refractory ulcerative colitis is associated with 3 times increased odds of venous thromboembolism compared with patients without tofacitinib exposure. See Video Abstract . TOFACITINIB SE ASOCIA CON UN MAYOR RIESGO DE TROMBOEMBOLISMO VENOSO POSTOPERATORIO EN PACIENTES CON COLITIS ULCEROSA: ANTECEDENTES:En 2019, la FDA emitió una advertencia de recuadro negro sobre un mayor riesgo de tromboembolismo venoso en pacientes con artritis reumatoide expuestos a tofacitinib. Hay datos limitados sobre el riesgo de tromboembolismo venoso postoperatorio en pacientes con colitis ulcerosa expuestos a tofacitinib.OBJETIVO:Evaluar si la exposición preoperatoria a tofacitinib se asocia con mayores probabilidades de tromboembolismo venoso postoperatorio.DISEÑO:Revisión retrospectiva.LUGARES:Centro médico académico terciario.PACIENTES:Pacientes consecutivos expuestos a tofacitinib dentro de las 4 semanas previas a la colectomía abdominal total o proctocolectomía total, con o sin ileostomía, entre 2014 y 2021, emparejados 1:2 para exposición a tofacitinib o ninguna exposición.INTERVENCIÓN(S):Exposición a tofacitinib versus ninguna exposición.PRINCIPALES MEDIDAS DE RESULTADO:Tasa de tromboembolismo venoso posoperatorio a los 90 días.RESULTADOS:Cuarenta y dos pacientes con exposición a tofacitinib y 84 pacientes de casos similares sin exposición a tofacitinib se sometieron a cirugía por colitis ulcerosa médicamente refractaria. Nueve (22,0%) pacientes expuestos a tofacitinib y 7 (8,5%) pacientes no expuestos fueron diagnosticados con tromboembolismo venoso dentro de los 90 días posteriores a la cirugía. En la regresión logística univariada, los pacientes expuestos a tofacitinib tuvieron 3,01 veces más probabilidades de desarrollar un tromboembolismo venoso dentro de los 90 días posteriores a la cirugía en comparación con los no expuestos ( p = 0,04, IC del 95 %: 1,03-8,79). Otros factores de riesgo de tromboembolismo venoso no se asociaron significativamente con el tromboembolismo venoso. Los tromboembolismos venosos en ambos grupos fueron más comúnmente trombosis de la vena portomesentérica (66,7% en los expuestos a tofacitinib y 42,9% en los no expuestos) y se diagnosticaron en una media de 23,2 días (rango, 3-90 días) después de la operación en los expuestos a tofacitinib y 7,9 días. (1-19 días) en los grupos no expuestos, respectivamente. No hubo diferencias estadísticamente significativas en la ubicación o el momento entre los dos grupos.LIMITACIONES:Carácter retrospectivo del estudio y sesgos asociados. La dependencia de tromboembolismos venosos diagnosticados clínicamente puede subestimar la tasa de incidencia real.CONCLUSIONES:La exposición a tofacitinib antes de la cirugía para la colitis ulcerosa médicamente refractaria se asocia con probabilidades 3 veces mayores de tromboembolismo venoso en comparación con los pacientes sin exposición a tofacitinib. (Traducción-Dr. Mauricio Santamaria ).

The mode of delivery does not influence the occurrence of post-partum perianal disease flares in patients with inflammatory bowel disease.

INTRODUCTION: Perianal disease occurs in up to 34% of inflammatory bowel disease (IBD) patients. An estimated 25% of women will become pregnant after the initial diagnosis, thus introducing the dilemma of whether mode of delivery affects perianal disease. The aim of our study was to analyze whether a cesarean section (C-section) or vaginal delivery influence perianal involvement. We hypothesized the delivery route would not alter post-partum perianal manifestations in the setting of previously healed perianal disease. METHODS: All consecutive eligible IBD female patients between 1997 and 2022 who delivered were included. Prior perianal involvement, perianal flare after delivery and delivery method were noted. RESULTS: We identified 190 patients with IBD who had a total of 322 deliveries; 169 (52%) were vaginal and 153 (48%) were by C-section. Nineteen women (10%) experienced 21/322 (6%) post-partum perianal flares. Independent predictors were previous abdominal surgery for IBD (OR, 2.7; 95% CI, 1-7.2; p = 0.042), ileocolonic involvement (OR, 3.3; 95% CI, 1.1-9.4; p = 0.030), previous perianal disease (OR, 22; 95% CI, 7-69; p < 0.001), active perianal disease (OR, 96; 95% CI, 21-446; p < 0.001) and biologic (OR, 4.4; 95% CI,1.4-13.6; p < 0.011) or antibiotic (OR, 19.6; 95% CI, 7-54; p < 0.001) treatment. Negative association was found for vaginal delivery (OR, 0.19; 95% CI, 0.06-0.61; p < 0.005). Number of post-partum flares was higher in the C-section group [17 (11%) vs. 4 (2%), p = 0.002]. CONCLUSIONS: Delivery by C-section section was not protective of ongoing perianal disease activity post-delivery, but should be recommended for women with active perianal involvement.

A phase IB/IIA study of ex vivo expanded allogeneic bone marrow-derived mesenchymal stem cells for the treatment of rectovaginal fistulizing Crohn's disease.

BACKGROUND: Crohn-related rectovaginal fistulas are notoriously difficult to treat. Studies of mesenchymal stem cells for the treatment of perianal Crohn fistulizing disease have largely excluded rectovaginal fistulas. The aim of this study was to determine the safety and efficacy of mesenchymal stem cells for refractory rectovaginal fistulizing Crohn disease. METHODS: A phase IB/IIA randomized control trial was performed in a 3:1, single-blinded study. Patients included were adult women with an anovaginal/rectovaginal fistula in the setting of Crohn disease. Seventy-five million mesenchymal stem cells were administered with a 22G needle after curettage and primary closure of the fistula tract at day 0 and month 3. Adverse and serious adverse events were recorded at post-procedure day 1, week 2, week 6, month 3, month 6, and month 12, along with clinical healing, magnetic resonance imaging, and patient-reported outcomes. RESULTS: A total of 19 patients were enrolled and treated-15 treatment and 4 control. There were no adverse or serious adverse events related to mesenchymal stem cell therapy. At 6 months, 50% of the treatment group and 0% of the control had complete clinical and radiographic healing; 91.7% of the treatment group had improvement at 6 months with only one patient having a lack of response, whereas only 50% of the control group had improvement at 6 months. CONCLUSION: Bone marrow-derived mesenchymal stem cells offer a safe alternative treatment approach for rectovaginal fistulas in the setting of Crohn disease. Complete healing was achieved in half of the patients.

Treatment effect of ex vivo expanded allogeneic bone marrow-derived mesenchymal stem cells for the treatment of fistulizing Crohn's disease are durable at 12 months.

BACKGROUND: Mesenchymal stem cells have been administered via direct injection to treat perianal Crohn's fistulizing disease. We herein sought to determine the safety and durability of treatment response to 12 months with 3 individual phase IB/IIA clinical trials of mesenchymal stem cells for refractory perianal, rectovaginal, and ileal pouch fistulas in the setting of Crohn disease. METHODS: Three phase IB/IIA randomized placebo-controlled single-blinded clinical trials were performed for (1) perianal fistulas, (2) rectovaginal fistula, and (3) ileal pouch in situ with anovaginal and/or perianal fistulas. Bone marrow-derived mesenchymal stem cells (75 million in 7.5 mL) were injected at the time of exam under anesthesia on day 0 and month 3. Outcome measures were adverse events and combined clinical and pelvic magnetic resonance imaging healing at month 6 and month 12. RESULTS: Across all 3 trials, 64 patients were enrolled; 49 were treatment and 15 were control. At 6 months, combined clinical and radiographic healing was achieved in 83.3%, 33.3%, and 30.8% of the perianal, rectovaginal, and pouch fistula treatment cohorts, respectively. At 12 months, the treatment response was durable, with 67.7% of perianal, 37.5% of rectovaginal, and 46.2% of peripouch fistulas maintaining complete clinical and radiographic healing. Two patients in the perianal fistula control cohort achieved combined clinical and radiographic healing at 12 months, whereas 0% of rectovaginal and pouch control patients healed. CONCLUSION: Bone marrow-derived mesenchymal stem cells offer a safe and effective alternative treatment approach for severe perianal, rectovaginal, and peripouch fistulizing Crohn's disease. Treatment results are durable at 12 months.

Salvage Surgery: An Effective Therapy in the Management of Ileoanal Pouch Prolapse.

BACKGROUND: Restorative proctocolectomy with IPAA is the surgical treatment of choice for patients requiring surgery for IBD and, less frequently, for other pathologies. Pouch prolapse is a rare complication that compromises pouch function and negatively affects patients' quality of life. OBJECTIVE: This study aimed to describe our experience from a single high-volume center in this infrequent condition. DESIGN: Restrospective cohort study of a prospectively maintained, Institutional Review Board-approved database. SETTINGS: All consecutive eligible patients with IPAA and pouch prolapse were identified from 1990 to 2021. PATIENTS: Patients with full-thickness prolapse treated by pouch pexy were included. INTERVENTIONS: Pouch pexy (with/without mesh). MAIN OUTCOME MEASURES: Success rate of pouch pexy, defined as no recurrence of prolapse. RESULTS: A total of 4791 patients underwent IPAA; 7 (0.1%) were diagnosed with full-thickness prolapse. An additional 18 patients who underwent IPAA and had full-thickness prolapse were referred from outside institutions. Among 25 included patients, 16 (64.0%) were women, and the overall mean age was 35.6 ± 13.4 years. The time interval from initial pouch formation to prolapse was 4.2 (interquartile range, 1.1-8.5) years. Nine patients (36.0%) underwent previous treatment for prolapse. All patients presented with symptoms and physical examination compatible with full-thickness prolapse. Twenty patients (80.0%) underwent surgical pouch pexy without mesh and 5 (20.0%) had pouch pexy with mesh placement. A diverting ileostomy was performed in 1 patient (4.0%) before pouch pexy and in 8 patients (32.0%) at the time of surgical prolapse correction. After surgery, recurrent prolapse was noted in 3 patients (12.0%) at a median of 6.9 (interquartile range, 5.2-8.3) months. LIMITATIONS: Retrospective study, small sample size thus prone to selection, and referral biases, which may limit the generalizability of our findings. CONCLUSION: Pouch prolapse can be effectively treated with salvage surgery. Surgical intervention is safe and provides acceptable outcomes. See Video Abstract. CIRUGA DE RESCATE UNA TERAPIA EFICAZ EN EL MANEJO DEL PROLAPSO DE LA BOLSA ILEOANAL: ANTECEDENTES:La proctocolectomía restauradora con anastomosis reservorio ileoanal es el tratamiento quirúrgico de elección para aquellos pacientes que requieren cirugía por enfermedad inflamatoria intestinal y, con menor frecuencia, por otras patologías. El prolapso de la bolsa es una complicación rara que compromete la función de la bolsa y afecta de manera negativa la calidad de vida de los pacientes.OBJETIVO:Describir nuestra experiencia de un solo centro de alto volumen en esta condición poco frecuente.DISEÑO:Estudio de cohorte retrospectivo de una base de datos mantenida prospectivamente aprobada por el IRB.AJUSTES/PACIENTES:Fueron identificados y elegibles de manera consecutiva todos los pacientes con anastomosis de bolsa ileoanal y prolapso de bolsa entre 1990 y 2021. Se incluyeron pacientes con prolapso de bolsa de espesor total tratados con pexia.INTERVENCIONES:Pexia de la bolsa (con/sin malla).PRINCIPALES MEDIDAS DE RESULTADO:Tasa de éxito de la pexia de la bolsa, definida como ausencia de recurrencia del prolapso.RESULTADOS:Un total de 4.791 pacientes fueron sometidos a anastomosis de bolsa ileoanal; siete (0,1%) fueron diagnosticados con prolapso de espesor total. Otros 18 pacientes con anastomosis de reservorio ileoanal fueron derivados de instituciones externas. De entre los 25 pacientes incluidos, 16 (64,0 %) eran mujeres y la edad media promedio fue de 35,6+/-13,4 años. El intervalo de tiempo desde la creación inicial de la bolsa hasta el prolapso fue de 4,2 (IQR 1,1-8,5) años. Nueve (36,0 %) pacientes fueron sometidos a tratamiento previo para el prolapso (fisioterapia n = 4, pexia de la bolsa n = 2, pexia de la bolsa con malla n = 2, resección de la mucosa n = 1). Todos los pacientes presentaron síntomas y exploración física compatibles con prolapso de espesor total. Veinte (80,0%) pacientes se sometieron a pexia de bolsa quirúrgica sin malla y cinco (20,0%) se sometieron a pexia de bolsa con colocación de malla. Se realizó una ileostomía de derivación en un (4,0%) paciente antes de la pexia de la bolsa y en ocho (32,0%) pacientes en el momento de la corrección quirúrgica del prolapso. Posterior a la cirugía, se observó prolapso recurrente en tres pacientes (12,0 %) con una mediana de 6,9 (IQR 5,2-8,3) meses.LIMITACIONES:Estudio retrospectivo, pequeño tamaño de muestra, por lo tanto, propenso a sesgos de selección y referencia que pueden limitar la generalización de nuestros hallazgos.CONCLUSIÓN:El prolapso de la bolsa ileoanal puede tratarse de manera efectiva mediante la cirugía de rescate. La intervención quirúrgica es segura y proporciona resultados aceptables. (Traducción-Dr. Mauricio Santamaria ).

Safety and Efficacy of Intravenous ExoFlo in the Treatment of Complex Regional Pain Syndrome.

BACKGROUND: Complex regional pain syndrome (CRPS) is an extremely painful disorder driven primarily by inflammation. OBJECTIVES: We hypothesized that the immunomodulatory biologic, ExoFloTM, composed of bone marrow mesenchymal stem cell-derived extracellular vesicles, could be safely administered to CRPS patients and alleviate symptoms. STUDY DESIGN: Ten patients received 2 intravenous (IV) infusions, each containing 15 mL ExoFlo, on day one and day 4. A series of tests were performed at baseline (day 0, prior to infusion), week one, and months one, 3, and 6 after the second infusion. SETTING: All patients were treated in one of 2 outpatient pain management clinics in Orange County, CA. METHODS: Testing for clinical improvement included: visual analog scale of pain, brief pain inventory, 36-item short-form questionnaire, range of motion analysis, and jamar dynamometer testing. RESULTS: No serious adverse events related to ExoFlo treatment occurred. Statistically significant improvements in pain and motion assessments occurred across the patient pool. LIMITATIONS: This study was limited by its patient number enrolled (10), it lacked a control arm, and one patient who dropped out of the study. CONCLUSIONS: IV delivery of ExoFlo appears safe in patients with CRPS. In addition, ExoFlo exhibited efficacy in addressing CRPS symptoms. Given the lack of effective and safe treatments available to CRPS patients, these results suggest that further studies are warranted to explore and validate this potential treatment for CRPS.