Debamestrocel multimodal effects on biomarker pathways in amyotrophic lateral sclerosis are linked to clinical outcomes.

INTRODUCTION/AIMS: Biomarkers have shown promise in amyotrophic lateral sclerosis (ALS) research, but the quest for reliable biomarkers remains active. This study evaluates the effect of debamestrocel on cerebrospinal fluid (CSF) biomarkers, an exploratory endpoint. METHODS: A total of 196 participants randomly received debamestrocel or placebo. Seven CSF samples were to be collected from all participants. Forty-five biomarkers were analyzed in the overall study and by two subgroups characterized by the ALS Functional Rating Scale-Revised (ALSFRS-R). A prespecified model was employed to predict clinical outcomes leveraging biomarkers and disease characteristics. Causal inference was used to analyze relationships between neurofilament light chain (NfL) and ALSFRS-R. RESULTS: We observed significant changes with debamestrocel in 64% of the biomarkers studied, spanning pathways implicated in ALS pathology (63% neuroinflammation, 50% neurodegeneration, and 89% neuroprotection). Biomarker changes with debamestrocel show biological activity in trial participants, including those with advanced ALS. CSF biomarkers were predictive of clinical outcomes in debamestrocel-treated participants (baseline NfL, baseline latency-associated peptide/transforming growth factor beta1 [LAP/TGFß1], change galectin-1, all p < .01), with baseline NfL and LAP/TGFß1 remaining (p < .05) when disease characteristics (p < .005) were incorporated. Change from baseline to the last measurement showed debamestrocel-driven reductions in NfL were associated with less decline in ALSFRS-R. Debamestrocel significantly reduced NfL from baseline compared with placebo (11% vs. 1.6%, p = .037). DISCUSSION: Following debamestrocel treatment, many biomarkers showed increases (anti-inflammatory/neuroprotective) or decreases (inflammatory/neurodegenerative) suggesting a possible treatment effect. Neuroinflammatory and neuroprotective biomarkers were predictive of clinical response, suggesting a potential multimodal mechanism of action. These results offer preliminary insights that need to be confirmed.

Evaluation of neurotrophic factor secreting mesenchymal stem cells in progressive multiple sclerosis.

BACKGROUND: Autologous mesenchymal stem cell neurotrophic factor-secreting cells (NurOwn®) have the potential to modify underlying disease mechanisms in progressive multiple sclerosis (PMS). OBJECTIVE: This open-label phase II study was conducted to evaluate safety/efficacy of three intrathecal cell treatments. METHODS: Eighteen participants with non-relapsing PMS were treated. The primary endpoint was safety. Secondary endpoints included: cerebrospinal fluid (CSF) biomarkers; timed 25-foot walk speed, nine-hole peg test (9-HPT), low-contrast letter acuity, symbol digit modalities test, and 12-item multiple sclerosis (MS) walking scale. Seventeen participants received all treatments. RESULTS: No deaths/adverse events related to worsening of MS, clinical/magnetic resonance imaging (MRI) evidence of disease activation, and clinically significant changes in safety lab results were reported. Two participants developed symptoms of low back and leg pain, consistent with a diagnosis of arachnoiditis, occurring in one of three intrathecal treatments in both participants. Nineteen percent of treated participants achieved pre-specified ⩾ 25% improvements in timed 25-foot walk speed/nine-HPT at 28 weeks compared to baseline, along with consistent efficacy signals for pre-specified response criteria across other secondary efficacy outcomes. CSF neuroprotective factors increased, and inflammatory biomarkers decreased after treatment, consistent with the proposed mechanism of action. CONCLUSION: Based on these encouraging preliminary findings, further confirmation in a randomized study is warranted.

A randomized placebo-controlled phase 3 study of mesenchymal stem cells induced to secrete high levels of neurotrophic factors in amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative illness with great unmet patient need. We aimed to evaluate whether mesenchymal stem cells induced to secrete high levels of neurotrophic factors (MSC-NTF), a novel autologous cell-therapy capable of targeting multiple pathways, could safely slow ALS disease progression. METHODS: This randomized, double-blind, placebo-controlled study enrolled ALS participants meeting revised El Escorial criteria, revised ALS Functional Rating Scale (ALSFRS-R) ≥25 (screening) and ≥3 ALSFRS-R points decline prior to randomization. Participants received three treatments of MSC-NTF or placebo intrathecally. The primary endpoint evaluated efficacy of MSC-NTF through a responder analysis and safety. A change in disease progression post-treatment of ≥1.25 points/mo defines a clinical response. A pre-specified analysis leveraged baseline ALSFRS-R of 35 as a subgroup threshold. RESULTS: Overall, MSC-NTF treatment was well tolerated; there were no safety concerns. Thirty-three percent of MSC-NTF and 28% of placebo participants met clinical response criteria at 28 wk (odds ratio [OR] = 1.33, P = .45); thus, the primary endpoint was not met. A pre-specified analysis of participants with baseline ALSFRS-R ≥ 35 (n = 58) showed a clinical response rate at 28 wk of 35% MSC-NTF and 16% placebo (OR = 2.6, P = .29). Significant improvements in cerebrospinal biomarkers of neuroinflammation, neurodegeneration, and neurotrophic factor support were observed with MSC-NTF, with placebo unchanged. DISCUSSION: The study did not reach statistical significance on the primary endpoint. However, a pre-specified subgroup suggests that MSC-NTF participants with less severe disease may have retained more function compared to placebo. Given the unmet patient need, the results of this trial warrant further investigation.

Addressing heterogeneity in amyotrophic lateral sclerosis CLINICAL TRIALS.

Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disorder with complex biology and significant clinical heterogeneity. Many preclinical and early phase ALS clinical trials have yielded promising results that could not be replicated in larger phase 3 confirmatory trials. One reason for the lack of reproducibility may be ALS biological and clinical heterogeneity. Therefore, in this review, we explore sources of ALS heterogeneity that may reduce statistical power to evaluate efficacy in ALS trials. We also review efforts to manage clinical heterogeneity, including use of validated disease outcome measures, predictive biomarkers of disease progression, and individual clinical risk stratification. We propose that personalized prognostic models with use of predictive biomarkers may identify patients with ALS for whom a specific therapeutic strategy may be expected to be more successful. Finally, the rapid application of emerging clinical and biomarker strategies may reduce heterogeneity, increase trial efficiency, and, in turn, accelerate ALS drug development.

NurOwn, phase 2, randomized, clinical trial in patients with ALS: Safety, clinical, and biomarker results.

OBJECTIVE: To determine the safety and efficacy of mesenchymal stem cell (MSC)-neurotrophic factor (NTF) cells (NurOwn®, autologous bone marrow-derived MSCs, induced to secrete NTFs) delivered by combined intrathecal and intramuscular administration to participants with amyotrophic lateral sclerosis (ALS) in a phase 2 randomized controlled trial. METHODS: The study enrolled 48 participants randomized 3:1 (treatment: placebo). After a 3-month pretransplant period, participants received 1 dose of MSC-NTF cells (n = 36) or placebo (n = 12) and were followed for 6 months. CSF was collected before and 2 weeks after transplantation. RESULTS: The study met its primary safety endpoint. The rate of disease progression (Revised ALS Functional Rating Scale [ALSFRS-R] slope change) in the overall study population was similar in treated and placebo participants. In a prespecified rapid progressor subgroup (n = 21), rate of disease progression was improved at early time points (p < 0.05). To address heterogeneity, a responder analysis showed that a higher proportion of treated participants experienced ≥1.5 points/month ALSFRS-R slope improvement compared to placebo at all time points, and was significant in rapid progressors at 4 and 12 weeks (p = 0.004 and 0.046, respectively). CSF neurotrophic factors increased and CSF inflammatory biomarkers decreased in treated participants (p < 0.05) post-transplantation. CSF monocyte chemoattractant protein-1 levels correlated with ALSFRS-R slope improvement up to 24 weeks (p < 0.05). CONCLUSION: A single-dose transplantation of MSC-NTF cells is safe and demonstrated early promising signs of efficacy. This establishes a clear path forward for a multidose randomized clinical trial of intrathecal autologous MSC-NTF cell transplantation in ALS. CLASSIFICATION OF EVIDENCE: This phase II study provides Class I evidence.

miRNA profiling of NurOwn®: mesenchymal stem cells secreting neurotrophic factors.

BACKGROUND: MSC-NTF cells are Mesenchymal Stromal Cells (MSC) induced to express high levels of neurotrophic factors (NTFs) using a culture-medium based approach. MSC-NTF cells have been successfully studied in clinical trials for Amyotrophic Lateral Sclerosis (ALS) patients. MicroRNAs (miRNA) are short non-coding RNA molecules that coordinate post-transcriptional regulation of multiple gene targets. The purpose of this study was to determine whether the miRNA profile could provide a tool for MSC-NTF cell characterization and to distinguish them from the matched MSC from which they are derived. METHODS: NTF secretion in the culture supernatant of MSC-NTF cells was evaluated by ELISA assays. The Agilent microarray miRNA platform was used for pairwise comparisons of MSC-NTF cells to MSC. The differentially expressed miRNAs and putative mRNA targets were validated using qPCR analyses. RESULTS: Principal component analysis revealed two distinct clusters based on cell type (MSC and MSC-NTFs). Nineteen miRNAs were found to be upregulated and 22 miRNAs were downregulated in MSC-NTF cells relative to the MSC cells of origin. Further validation of differentially expressed miRNAs confirmed that miR-3663 and miR-132 were increased 18.5- and 4.06-fold, respectively while hsa-miR-503 was reduced more than 15-fold, suggesting that miRNAs could form the basis of an MSC-NTF cell characterization assay. In an analysis of the miRNA mRNA targets, three mRNA targets of hsa-miR-132-3p (HN-1, RASA1 and KLH-L11) were found to be significantly downregulated. CONCLUSIONS: We have demonstrated that MSC-NTF cells can be distinguished from their MSCs of origin by a unique miRNA expression profile. TRIAL REGISTRATION: Clinicaltrial.gov identifier NCT01777646 . Registered 12 December 2012.

Long term beneficial effect of neurotrophic factors-secreting mesenchymal stem cells transplantation in the BTBR mouse model of autism.

Autism spectrum disorders (ASD) are neurodevelopmental disabilities characterized by severe impairment in social communication skills and restricted, repetitive behaviors. We have previously shown that a single transplantation of mesenchymal stem cells (MSC) into the cerebral lateral ventricles of BTBR autistic-like mice resulted in an improvement across all diagnostic criteria of ASD. We suggested that brain-derived neurotrophic factor (BDNF), a protein which supports the survival and regeneration of neurons secreted by MSC, largely contributed to the beneficial behavioral effect. In this study, we investigated the behavioral effects of transplanted MSC induced to secrete higher amounts of neurotrophic factors (NurOwn®), on various ASD-related behavioral domains using the BTBR mouse model of ASD. We demonstrate that NurOwn® transplantation had significant advantages over MSC transplantation in terms of improving communication skills, one and six months following treatment, as compared to sham-treated BTBR mice. Furthermore, NurOwn® transplantation resulted in reduced stereotypic behavior for as long as six months post treatment, compared to the one month improvement observed in the MSC treated mice. Notably, NurOwn® treatment resulted in improved cognitive flexibility, an improvement that was not observed by MSC treatment. Both MSC and NurOwn® transplantation induced an improvement in social behavior that lasted for six months. In conclusion, the present study demonstrates that a single transplantation of MSC or NurOwn® have long-lasting benefits, while NurOwn® may be superior to MSC treatment.

Safety and Clinical Effects of Mesenchymal Stem Cells Secreting Neurotrophic Factor Transplantation in Patients With Amyotrophic Lateral Sclerosis: Results of Phase 1/2 and 2a Clinical Trials.

IMPORTANCE: Preclinical studies have shown that neurotrophic growth factors (NTFs) extend the survival of motor neurons in amyotrophic lateral sclerosis (ALS) and that the combined delivery of these neurotrophic factors has a strong synergistic effect. We have developed a culture-based method for inducing mesenchymal stem cells (MSCs) to secrete neurotrophic factors. These MSC-NTF cells have been shown to be protective in several animal models of neurodegenerative diseases. OBJECTIVE: To determine the safety and possible clinical efficacy of autologous MSC-NTF cells transplantation in patients with ALS. DESIGN, SETTING, AND PARTICIPANTS: In these open-label proof-of-concept studies, patients with ALS were enrolled between June 2011 and October 2014 at the Hadassah Medical Center in Jerusalem, Israel. All patients were followed up for 3 months before transplantation and 6 months after transplantation. In the phase 1/2 part of the trial, 6 patients with early-stage ALS were injected intramuscularly (IM) and 6 patients with more advanced disease were transplanted intrathecally (IT). In the second stage, a phase 2a dose-escalating study, 14 patients with early-stage ALS received a combined IM and IT transplantation of autologous MSC-NTF cells. INTERVENTIONS: Patients were administered a single dose of MSC-NTF cells. MAIN OUTCOMES AND MEASURES: The primary end points of the studies were safety and tolerability of this cell therapy. Secondary end points included the effects of the treatment on various clinical parameters, such as the ALS Functional Rating Scale-Revised score and the respiratory function. RESULTS: Among the 12 patients in the phase 1/2 trial and the 14 patients in the phase 2a trial aged 20 and 75 years, the treatment was found to be safe and well tolerated over the study follow-up period. Most of the adverse effects were mild and transient, not including any treatment-related serious adverse event. The rate of progression of the forced vital capacity and of the ALS Functional Rating Scale-Revised score in the IT (or IT+IM)-treated patients was reduced (from -5.1% to -1.2%/month percentage predicted forced vital capacity, P < .04 and from -1.2 to 0.6 ALS Functional Rating Scale-Revised points/month, P = .052) during the 6 months following MSC-NTF cell transplantation vs the pretreatment period. Of these patients, 13 (87%) were defined as responders to either ALS Functional Rating Scale-Revised or forced vital capacity, having at least 25% improvement at 6 months after treatment in the slope of progression. CONCLUSIONS AND RELEVANCE: The results suggest that IT and IM administration of MSC-NTF cells in patients with ALS is safe and provide indications of possible clinical benefits, to be confirmed in upcoming clinical trials. TRIAL REGISTRATION: clinicaltrials.gov Identifiers: NCT01051882 and NCT01777646.

Safety of repeated transplantations of neurotrophic factors-secreting human mesenchymal stromal stem cells.

BACKGROUND: Therapies based on mesenchymal stem cells (MSC) have been shown to have potential benefit in several clinical studies. We have shown that, using a medium-based approach, MSC can be induced to secrete elevated levels of neurotropic factors, which have been shown to have protective effects in animal models of neurodegenerative diseases. These cells, designated MSC-NTF cells (Neurotrophic factor-secreting MSC, also known as NurOwn™) derived from the patient's own bone marrow, have been recently used for Phase I/II and Phase IIa clinical studies in patients with Amyotrophic Lateral Sclerosis (ALS). In these studies, ALS patients were subjected to a single administration of autologous MSC-NTF cells. The data from these studies indicate that the single administration of MSC-NTF cells is safe and well tolerated. In a recently published case report, it was shown that repeated MSC-NTF injections in an ALS patient treated on a compassionate basis were safe and well tolerated [Muscle Nerve 49:455-457, 2014]. METHODS: In the current study we studied the toxicity and tolerability of three consecutive intramuscular injections (IM) of cryopreserved human MSC-NTF cells in C57BL/B6 mice to investigate the effect of repeated administration of these cells. RESULTS: Monitoring of clinical signs and immune reactions showed that repeated injections of the cells did not lead to any serious adverse events. Pathology, histology and blood biochemistry parameters tested were found to be within normal ranges with no sign of tumor formation. CONCLUSIONS: Based on these results we conclude that repeated injections of human MSC-NTF are well tolerated in mice. The results of this study suggest that if the outcomes of additional clinical studies point to the need for repeated treatments, such option can be considered safe.