Mesenchymal Stem Cell Therapy Has Modest Benefits for Chronic Major Stroke

Mesenchymal stem cell (MSC) therapy with autologous serum produced some subtle leg motor improvement but did not alter modified Rankin scale (mRS) among patients with chronic major stroke. This was according to findings from a prospective, open-label, randomized controlled trial that was published in Neurology.

Study researchers recruited patients (N=54) with chronic major stroke for the STARTING-2 trial (ClinicalTrials.gov identifier: NCT01716481) at 4 university medical centers in South Korea. They randomly assigned patients in a 2:1 ratio to receive intravenous MSC (n=39) or standard care (n=15), and assessed them through 3 months for clinical outcomes.

Patients in the intervention and control arms of the study had a mean age of 63.03 (±14.36) and 64.27 (±13.25) years, 43.6% and 66.7% were men, and body mass index was 23.2 (±3.59) and 23.47 (±2.92) kg/m², respectively.

At 90 days, 33.3% of the patients in the treatment group and 26.7% of those in the control group had no decrease in mRS scores; these scores did not differ significantly between groups (P =.732).

No other endpoints were significantly different between groups including changes to Fugl-Meyer Assessment (P =.292), functional ambulatory category (P =.763), or motricity index of the side (P =.090) or arm (P =.741).

Recipients of the MSC, however, had increased average motricity index of the leg (14.8±23.8) compared with control group participants (2.6±13.0; P =.023), but the observed change in score was no longer significant after adjusting for possible cofactors (P =.129).

A higher percentage of patients in the MSC cohort were predicted to have poor clinical outcomes by Fugl-Meyer Assessment-lower limb but had a good response rate according to the Predict Recovery Potential (P =.032) and Predict Recovery Potential-II (P =.017) algorithms.

In the intervention group, 1 patient had an allergic reaction and 1 had a systemic complication. In the control group, 1 patient had recurrent stroke or transient ischemic attack.

This study was limited by its small sample size and open-label design. Because bone marrow aspiration could not be performed among the control group participants, blinding was not adequate.

These data indicated some potentially modest biological potential for the use of MSC among patients with chronic major stroke. Additional studies of cultivation techniques, patient-specific biomarkers, and circulating factors are needed to more accurately assess the potential therapeutic efficacy of MSC.

Reference

Chung JW, Chang WH, Bang OY, et al; STARTING-2 Collaborators. Efficacy and safety of intravenous mesenchymal stem cells for ischemic stroke. Neurology. 2021;96(7):e1012-e1023. doi:10.1212/WNL.0000000000011440