A long-term follow-up of safety and clinical efficacy of NTCELL® [Immunoprotected (Alginate-encapsulated) porcine choroid plexus cells for xenotransplantation] in patients with Parkinson's disease

IntroductionIn 2019, we published the results of a Phase IIb randomized controlled trial putaminal encapsulated porcine choroid plexus cell (termed NTCELL®) administration in patients with Parkinson's disease. This study failed to meet its primary efficacy end-point change UPDRS part III score ‘off’ state at 26-weeks post-implant. However, number secondary end-points reached statistical significance. We questioned whether longer follow-up, clinically significant improvements would be observed. For this reason, decided follow-up all periodically week 104. Herein, report long-term follow-up.MethodsAll 18 included original were re-assessed weeks 52, 78 and 104 At each time-point, motor non-motor function, quality life levodopa equivalent daily dose was assessed using standardized testing battery.ResultsAt 104, no differences scores observed any treatment groups compared baseline. Only single serious adverse event - hospitalisation due disease rigidity not responding changes medications – considered potentially related implant procedure. There evidence xenogeneic viral transmission.ConclusionUn-blinded, long-duration post-implantation showed that NTCELL® produces clinical benefit moderately advanced