HOLLYWOOD, FL—First-time data from a first-in-human stem cell trial for hemodialysis arteriovenous fistula (AVF) were presented by Sanjay Misra, MD, at the 31st annual International Symposium on Endovascular Therapy (ISET). The study also won the best poster award at the conference.
Dr. Misra explained that the primary patency of surgical creation of AV fistulas is estimated to be anywhere from 60% to 70%, meaning that there is a high failure rate of about 30%. He became interested in using stem cells derived from patients as their own therapy or their own drug.
After preliminary research was conducted in mice, the research group was granted an IND from the FDA to pursue the study, which was a phase I safety trial. “Our primary concern was around safety. Would these cells be creating more infections? Will they be less irritating with respect to fevers? So we did a randomized trial comparing patients who received stem cells or no cells and followed them for 1 year,” said Dr. Misra.
The study was blinded and prospective, and it took place at a single center in Rochester, Minnesota. According to Dr. Misra, the number of cells delivered was based on the surface area of the vessel using the following calculation: [(2π)(radius in cm)(5cm) x (500,000 cells per cm2]. Thus far, 16 patients have enrolled in the study (11 males and 5 females). Patients have an average age of approximately 65 years and an average BMI of 37.99.
After the procedure, the patients each underwent follow-up ultrasound studies to evaluate vascular remodeling of the AVF at 1, 2, 3, 6, and 12 months after AVF placement. Clinical outcomes and need for reintervention after creation of the fistula were also assessed.
All of the 16 patients in the study were hypotensive, 10 had a history of diabetes mellitus, 5 were on hemodialysis, 6 had a history of coronary artery disease, and 11 had dyslipidemia. “Nine patients have completed 1-year follow-up, and we’ve had no adverse events related to safety for stem cells,” said Dr. Misra.
At 1 month, the maturation rate for RCV fistula was 100% for stem cell patients compared with 66% for patients in the control group. Dr. Misra noted that at last follow-up, patients in the control group were receiving more interventions. Three patients in the control group underwent 5 fistulograms with 4 percutaneous transluminal angioplasties of the cannulation zone, compared with 1 patient in the stem cell group. “So we’re seeing an effect related to the cells, less frequency of interventions,” said Dr. Misra.
He continued, “The future is to continue with this trial, and also we’re in the process of filing an IDE for using this with angioplasty and periadventitial catheters.” Dr. Misra concluded his presentation by thanking everyone involved and noting that collaboration between radiologists, interventionalists, and regenerative medicine specialists was important to the study.