Treatment of degenerative disc disease with allogeneic mesenchymal stem cells: long-term follow-up results

Abstract

Degenerative disc disease (DDD) is a prevalent cause of chronic low back pain with limited long-term therapeutic options. This study reports the long-term outcomes of a randomized controlled trial evaluating intradiscal implantation of allogeneic bone marrow-derived mesenchymal stem cells (MSCs) in patients with symptomatic DDD. A total of 24 patients with chronic lumbar disc degeneration unresponsive to conservative management were randomized to receive a single intradiscal injection of 25 × 10⁶ allogeneic MSCs per affected disc (treatment group) or a sham procedure (control group). Patients were followed for a mean of 3.5 ± 0.1 years (approximately 42 months). Clinical effectiveness was evaluated using pain intensity, functional disability, and structural disc changes by magnetic resonance imaging. Long-term results demonstrated sustained reductions in pain and disability in the MSC-treated patients compared with controls. Radiological assessment showed decreased Pfirrmann grading over time in the MSC group, whereas controls exhibited progression of degeneration. The interventional procedure was well-tolerated with no serious treatment-related adverse events reported. These findings indicate that intradiscal allogeneic MSC therapy may provide durable symptom relief and objective structural benefits in DDD, although larger studies are required to define optimal dosing and broader applicability.