A Single-Blinded Randomized Controlled Trial of Mesenchymal Stem Cell Therapy for the Treatment of Osteoarthritis of the Knee with Active Control

Background: Osteoarthritis is most prevalent in the knee and drives the growing incidence of total knee arthroplasty. There is a need to explore non-surgical treatment options to increase the portfolio of alternatives available. The study aimed to determine the clinical response to an autologous bone marrow aspirate concentrate (BMAC) and platelet-rich plasma (PRP) intra-articular injection compared to an active comparator. Methods: The study was a prospective, single-blinded, randomized controlled pilot study. Participants with diagnosed knee osteoarthritis were allocated to one of two treatment groups to receive a BMAC injection immediately followed by a PRP injection or a single injection of Gel-One® crosslinked hyaluronate (HA). Outcomes were assessed at 3, 6, and 12 months post-treatment. Results: Significant improvements were observed in both treatment groups for all Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales with the exception of the symptoms assessment at 12 months in the HA group. BMAC KOOS scores peaked at 12 months, while HA KOOS scores generally peaked at 6 months. The gap in mean scores at 12 months in favor of the BMAC group did not reach statistical significance. Secondary outcomes included a greater reduction in pain at 12 months in the BMAC group (-3.13 points; 95% CI: -3.96, -3.29) compared to the HA group (-1.56 points; 95% CI: -2.59, -0.53; p= 0.02) via the numeric pain rating scale. Conclusions: Results demonstrate that both treatment groups experienced clinically and statistically significant improvement across the KOOS subscales. While BMAC has shown promise in the treatment of knee OA, there is a need for multi-center investigations with larger sample sizes, an extended follow-up, and placebo-based control. ClinicalTrials.gov Identifier: NCT02958267.