Intra-articular injection of two different doses of autologous bone marrow mesenchymal stem cells versus hyaluronic acid in the treatment of knee osteoarthritis: long-term follow up of a multicenter randomized controlled clinical trial (phase I/II)

Lamo-Espinosa JM, Mora G, Blanco JF, et al. · Journal of Translational Medicine

VAS separated from control in both cell arms at 4 years - median 2 (IQR 2, 5) on the low dose and 3 (3, 4) on the high dose against 7 (6, 7) on control, from baseline medians of 7, 6 and 5 (low vs control p=0.01, high vs control p=0.004). WOMAC separated in the low-dose arm only: the figure reports the high dose against control as not significant, and the paper gives the low-dose value three ways - p=0.043 in the abstract, p=0.04 in the results text and p=0.01 in the figure caption. Median WOMAC change was +4 points on control, -18 on the low dose and -10 on the high dose. No clinical difference was found between the two cell doses.

Population

The 30-patient CMM-ART cohort at 4 years: 27 were reachable and 25 entered the analysis (9 control, 8 low dose, 8 high dose)

Intervention

Autologous BM-MSCs (10 or 100 million) plus HA

Comparator

HA alone

Limitations

Eight to nine patients per arm at 4 years, open-label at follow-up. The control arm is not clean: two of its nine had platelet-rich plasma injected into the study knee during follow-up, and one underwent knee replacement before the final data collection. Kellgren-Lawrence grade was unevenly distributed at baseline without reaching significance (p=0.585). Funded by the Instituto de Salud Carlos III and regional public bodies, with no manufacturer involved and no competing interests declared.