Clinical Outcomes of Transplanted Modified Bone Marrow-Derived Mesenchymal Stem Cells in Stroke: A Phase 1/2a Study.

BACKGROUND AND PURPOSE: Preclinical data suggest that cell-based therapies have the potential to improve stroke outcomes. METHODS: Eighteen patients with stable, chronic stroke were enrolled in a 2-year, open-label, single-arm study to evaluate the safety and clinical outcomes of surgical transplantation of modified bone marrow-derived mesenchymal stem cells (SB623). RESULTS: All patients in the safety population (N=18) experienced at least 1 treatment-emergent adverse event. Six patients experienced 6 serious treatment-emergent adverse events; 2 were probably or definitely related to surgical procedure; none were related to cell treatment. All serious treatment-emergent adverse events resolved without sequelae. There were no dose-limiting toxicities or deaths. Sixteen patients completed 12 months of follow-up at the time of this analysis. Significant improvement from baseline (mean) was reported for: (1) European Stroke Scale: mean increase 6.88 (95% confidence interval, 3.5-10.3; P<0.001), (2) National Institutes of Health Stroke Scale: mean decrease 2.00 (95% confidence interval, -2.7 to -1.3; P<0.001), (3) Fugl-Meyer total score: mean increase 19.20 (95% confidence interval, 11.4-27.0; P<0.001), and (4) Fugl-Meyer motor function total score: mean increase 11.40 (95% confidence interval, 4.6-18.2; P<0.001). No changes were observed in modified Rankin Scale. The area of magnetic resonance T2 fluid-attenuated inversion recovery signal change in the ipsilateral cortex 1 week after implantation significantly correlated with clinical improvement at 12 months (P<0.001 for European Stroke Scale). CONCLUSIONS: In this interim report, SB623 cells were safe and associated with improvement in clinical outcome end points at 12 months. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01287936.

Two-year safety and clinical outcomes in chronic ischemic stroke patients after implantation of modified bone marrow-derived mesenchymal stem cells (SB623): a phase 1/2a study.

OBJECTIVE: The aim of this study was to evaluate the safety and clinical outcomes associated with stereotactic surgical implantation of modified bone marrow-derived mesenchymal stem cells (SB623) in patients with stable chronic ischemic stroke. METHODS: This was a 2-year, open-label, single-arm, phase 1/2a study; the selected patients had chronic motor deficits between 6 and 60 months after nonhemorrhagic stroke. SB623 cells were administered to the target sites surrounding the subcortical stroke region using MRI stereotactic image guidance. RESULTS: A total of 18 patients were treated with SB623 cells. All experienced at least 1 treatment-emergent adverse event (TEAE). No patients withdrew due to adverse events, and there were no dose-limiting toxicities or deaths. The most frequent TEAE was headache related to the surgical procedure (88.9%). Seven patients experienced 9 serious adverse events, which resolved without sequelae. In 16 patients who completed 24 months of treatment, statistically significant improvements from baseline (mean) at 24 months were reported for the European Stroke Scale (ESS) score, 5.7 (95% CI 1.4-10.1, p < 0.05); National Institutes of Health Stroke Scale (NIHSS) score, -2.1 (95% CI -3.3 to -1.0, p < 0.01), Fugl-Meyer (F-M) total score, 19.4 (95% CI 9.9-29.0, p < 0.01); and F-M motor scale score, 10.4 (95% CI 4.0-16.7, p < 0.01). Measures of efficacy reached plateau by 12 months with no decline thereafter. There were no statistically significant changes in the modified Rankin Scale score. The size of transient lesions detected by T2-weighted FLAIR imaging in the ipsilateral cortex at weeks 1-2 postimplantation significantly correlated with improvement in ESS (0.619, p < 0.05) and NIHSS (-0.735, p < 0.01) scores at 24 months. CONCLUSIONS: In this completed 2-year phase 1/2a study, implantation of SB623 cells in patients with stable chronic stroke was safe and was accompanied by improvements in clinical outcomes.Clinical trial registration no.: NCT01287936 (clinicaltrials.gov).

Stem cell-paved biobridge facilitates neural repair in traumatic brain injury.

Modified mesenchymal stromal cells (MSCs) display a unique mechanism of action during the repair phase of traumatic brain injury by exhibiting the ability to build a biobridge between the neurogenic niche and the site of injury. Immunohistochemistry and laser capture assay have visualized this biobridge in the area between the neurogenic subventricular zone and the injured cortex. This biobridge expresses high levels of extracellular matrix metalloproteinases (MMPs), which are initially co-localized with a stream of transplanted MSCs, but later this region contains only few to non-detectable grafts and becomes overgrown by newly recruited host cells. We have reported that long-distance migration of host cells from the neurogenic niche to the injured brain site can be attained via these transplanted stem cell-paved biobridges, which serve as a key regenerative process for the initiation of endogenous repair mechanisms. Thus, far the two major schools of discipline in stem cell repair mechanisms support the idea of "cell replacement" and the bystander effects of "trophic factor secretion." Our novel observation of stem cell-paved biobridges as pathways for directed migration of host cells from neurogenic niche toward the injured brain site adds another mode of action underlying stem cell therapy. More in-depth investigations on graft-host interaction will likely aid translational research focused on advancing this stem cell-paved biobridge from its current place, as an equally potent repair mechanism as cell replacement and trophic factor secretion, into a new treatment strategy for traumatic brain injury and other neurological disorders.

Stem cell recruitment of newly formed host cells via a successful seduction? Filling the gap between neurogenic niche and injured brain site.

Here, we report that a unique mechanism of action exerted by stem cells in the repair of the traumatically injured brain involves their ability to harness a biobridge between neurogenic niche and injured brain site. This biobridge, visualized immunohistochemically and laser captured, corresponded to an area between the neurogenic subventricular zone and the injured cortex. That the biobridge expressed high levels of extracellular matrix metalloproteinases characterized initially by a stream of transplanted stem cells, but subsequently contained only few to non-detectable grafts and overgrown by newly formed host cells, implicates a novel property of stem cells. The transplanted stem cells manifest themselves as pathways for trafficking the migration of host neurogenic cells, but once this biobridge is formed between the neurogenic site and the injured brain site, the grafted cells disappear and relinquish their task to the host neurogenic cells. Our findings reveal that long-distance migration of host cells from the neurogenic niche to the injured brain site can be achieved through transplanted stem cells serving as biobridges for initiation of endogenous repair mechanisms. This is the first report of a stem cell-paved "biobridge". Indeed, to date the two major schools of discipline in stem cell repair mechanism primarily support the concept of "cell replacement" and bystander effects of "trophic factor secretion". The present novel observations of a stem cell seducing a host cell to engage in brain repair advances basic science concepts on stem cell biology and extracellular matrix, as well as provokes translational research on propagating this stem cell-paved biobridge beyond cell replacement and trophic factor secretion for the treatment of traumatic brain injury and other neurological disorders.

Talactoferrin alfa, a recombinant human lactoferrin promotes healing of diabetic neuropathic ulcers: a phase 1/2 clinical study.

BACKGROUND: Talactoferrin alfa, a recombinant form of human lactoferrin, is a novel immunomodulatory protein with demonstrated ulcer healing properties in animal models. METHODS: A phase 1/2 clinical study was conducted at 7 clinical sites to determine if talactoferrin can improve wound healing in diabetic patients with foot ulceration. Fifty-five patients with diabetic neuropathic foot ulcers participated in this 2-phase study. In phase 1, groups of 3 patients each received open-label 1%, 2.5%, or 8.5% talactoferrin gel twice daily, in a sequential design, to their ulcer for 30 days. No drug-related adverse events were found at any dose level. Phase 2 was a randomized, placebo-controlled, single-blind study of 2.5% and 8.5% gels, with patients equally divided between the 3 groups. In combination with good wound care, treatment was administered topically twice daily to the ulcers for 12 weeks. The primary endpoint was the incidence of > or = 75% healing (relative to baseline size). RESULTS: The study, which in phase 2 was powered to detect a difference between the placebo and combined talactoferrin arms with P < .1, met the primary objective. The groups receiving the 2.5% (n = 15) and 8.5% (n = 15) gels had twice the incidence of > or = 75% reduction in ulcer size compared with the placebo group (n = 16): 47%, 53%, and 25%, respectively. On an intent-to-treat basis, the combination of the 2 active groups when compared with the placebo group showed a strong trend toward statistical significance (P = .09). There were no talactoferrin-related adverse events or laboratory abnormalities. CONCLUSIONS: Topical talactoferrin appears to be safe and well tolerated and improves healing of diabetic neuropathic ulcers.