Umbilical cord-derived mesenchymal stem cells for treating osteoarthritis of the knee: a single-arm, open-label study

Background: Despite being a common cause of quality-of-life impairment, there are no efficacious therapies that could prevent the progression of knee osteoarthritis (KOA). We conducted an open-label trial of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) and hyaluronic acid (HA) for treating KOA. Methods: This open-label study was conducted from July 2015 to December 2018 at Cipto Mangunkusumo Hospital, Jakarta, Indonesia. Patients diagnosed with KOA were injected three times, comprising of 10 × 106 units of hUC-MSCs in 2-ml secretome implantation and 2-ml hyaluronic acid (HA) injection in the first week, followed with 2-ml HA injection twice in the second and third week. Results: Twenty-nine subjects (57 knees) were recruited. Seventeen (58.6%) subjects were male, and the mean age was 58.3 ± 9.6 years. Thirty-three (57.9%) knees were classified into Kellgren–Lawrence grade I–II KOA (mild OA). hUC-MSCs significantly decreased pain measured by visual analogue scale in severe KOA from initial to 6th month follow-up [5 ± 2.97 to 3.38 ± 2.44 (p = 0.035)]. The International Knee Documentation Committee score significantly increased at 6th month follow-up (53.26 ± 16.66 to 65.49 ± 13.01, p < 0.001, in subjects with grade I–II and 48.84 ± 18.41 to 61.83 ± 18.83, p = 0.008, in subjects with severe KOA). The Western Ontario and McMaster Universities Osteoarthritis decreased significantly in both groups from initial to 6th month follow-up (from 22.55 ± 15.94 to 13.23 ± 10.29, p = 0.003, and from 27.57 ± 15.99 to 17.92 ± 19.1, p = 0.003, in those with mild and severe KOA, respectively). Conclusions: hUC-MSCs could be a potentially new regenerative treatment for KOA. The maximum effect of hUC-MSCs was achieved after 6 months of injection. Level of evidence: Therapeutic level II.