SB623 Stem Cell Therapy to Regain Motor Function in TBI

Masahito Kawabori, MD, PhD

The recent 1-year double-blind, randomized, surgical sham-controlled, phase 2 STEMTRA trial (NCT02416492), which investigated the efficacy and safety of allogeneic modified bone marrow-derived mesenchymal stromal/stem cell (MSC) implantation (dubbed SB623 and developed by SanBio), read out results that suggest the treatment is well-tolerated and efficacious for patients with traumatic brain injury (TBI).

The least-squares mean difference was 6.0 points (95% CI, 0.3-1.8; P = .04) on the Fugl-Meyer Motor Scale (FMSS) between patients treated with SB623 and the control group. A clinically meaningful improvement of ≥10 points on FMSS score was achieved by 39.1% of the SB623 pooled group versus 6.7% of controls (P = .039). 

NeurologyLive reached out to Masahito Kawabori, MD, PhD, associate professor, Department of Neuronal Cell Therapy, Hokkaido University, to learn more about SB623 and stem cell therapy for TBI. He spoke to his outlook on the use of the therapy, and discussed other areas that SB623 is being investigated in.

NeurologyLive: What are some challenges that physicians face in treating TBI?

Masahito Kawabori, MD, PhD: Right now, unfortunately, there aren’t many efficient treatment options for chronic brain injury patients. So, we're still looking for a new treatment method, which can cure patients’ paralysis. If patients need wheelchairs, we want to help them to walk again. With current treatment options, there’s nothing we can offer right now to address that. That's the problem.

There’s only rehab, but rehab doesn’t really help patients regain their abilities. It only prevents decline in the patient’s abilities.

What's your outlook on stem cell implantation in TBI or other areas you’ve investigated like stroke? 

The results we saw with SB623 were very good; it enabled patients in wheelchairs to walk again. But we still have a lot to learn, such as, where is the best place to inject the SB623 cells? We’re not yet sure which injection sites will yield the best functional recovery. In the future, we need to answer those questions. I think that’s one of the most important questions we must answer.

Are there any other areas you'd like to investigate next with SB623?

Yes, for stroke, ischemic stroke specifically, because there are more patients with ischemic stroke than TBI. We’re also looking at SB623 efficacy in Alzheimer disease and Parkinson disease which are currently uncurable. I believe that SB623 has the potential to regain functional benefits for the patient.

Is there anything else that you'd like clinicians to know about SB623?

I would like physicians to just wait a little longer for the coming of a new treatment which will bring about a new field in neurosurgery. Stem cell therapy is just around the corner. So, I'm really excited to launch this new field of treatments.

Transcript edited for clarity.

REFERENCE

Kawabori M, Weintraub AH, Imai H, et al. Cell therapy for chronic TBI: Interim analysis of the randomized controlled STEMTRA trial. Neurology. Published online January 4, 2021. doi: 10.1212/WNL.0000000000011450