Phase I study of intravenous low-dose granulocyte colony-stimulating factor in acute and subacute ischemic stroke

Efficacy and Safety of Sovateltide in Patients with Acute Cerebral Ischaemic Stroke: A Randomised, Double-Blind, Placebo-Controlled, Multicentre, Phase III Clinical Trial

BACKGROUND AND OBJECTIVES

Sovateltide (Tycamzzi™), an endothelin-B (ET-B) receptor agonist, increases cerebral blood flow, has anti-apoptotic activity, and promotes neural repair following cerebral ischaemic stroke. The objectives of this study were to evaluate the efficacy and safety of sovateltide in adult participants with acute cerebral ischaemic stroke.

METHODS

This was a randomised, double-blind, placebo-controlled, multicentre, Phase III clinical trial of sovateltide in participants with cerebral ischaemic stroke receiving standard of care (SOC) in India. Patients aged 18-78 years presenting up to 24 h after the onset of symptoms with radiologic confirmation of ischaemic stroke and a National Institutes of Health Stroke Scale score (NIHSS) of ≥ 6 were enrolled. Patients with recurrent stroke, receiving endovascular therapy, or with intracranial haemorrhage were excluded. The study drug (saline or sovateltide [0.3 µg/kg] was administered intravenously in three doses at 3 ± 1 h intervals on Days 1, 3, and 6, and follow-up was 90 days). The Multivariate Imputation by Chained Equations (MICE) was used to impute the missing assessments on the endpoints. An unpaired t-test, two-way analysis of variance with Tukey's multiple comparison test, and the Chi-square test were used for the statistical analysis. The objective was to determine at Day 90 (1) the number of patients with a modified Rankin Scale score (mRS) 0-2, and (2) the number of patients with an NIHSS 0-5 at 90 days.

RESULTS

Patients were randomised with 80 patients in the sovateltide and 78 in the control group. Patients received the investigational drug at about 18 h of stroke onset in both control and sovateltide groups. The median NIHSS at randomisation was 10.00 (95% CI 9.99-11.65) in the control group and 9.00 (95% CI 9.11-10.46) in the sovateltide group. Seventy patients completed the 90-day follow-up in the control group and 67 in the sovateltide group. The proportion of intention-to-treat (ITT) patients with mRS 0-2 score at Day 90 post-randomisation was 22.67% higher (odds ratio [OR] 2.75, 95% CI 1.37-5.57); similarly, the proportion of patients with NIHSS score of 0-5 at Day 90 was 17.05% more (OR 2.67, 95% CI 1.27-5.90) in the sovateltide group than in the control group. An improvement of ≥ 2 points on the mRS was observed in 51.28% and 72.50% of patients in the control and sovateltide groups, respectively (OR 2.50, 95% CI 1.29-4.81). Seven of 78 patients (8.97%) in the control group and 7 of 80 (8.75%) in the sovateltide group developed intracranial haemorrhage (ICH). The adverse events were not related to sovateltide.

CONCLUSIONS

The sovateltide group had a greater number of cerebral ischaemic stroke patients with lower mRS and NIHSS scores at 90 days post-treatment than the control group. This trial supported the regulatory approval of sovateltide in India, but a multinational RESPECT-ETB trial will be conducted for US approval.

TRIAL REGISTRATION

Clinical Trials Registry, India (CTRI/2019/09/021373) and the United States National Library of Medicine, ClinicalTrials.gov (NCT04047563).

Albumin adjuvant therapy for acute ischemic stroke with large vessel occlusion (AMASS-LVO): rationale, design, and protocol for a phase 1, open-label, clinical trial

BACKGROUND

Acute ischemic stroke (AIS) is an acute brain injury caused by sudden occlusion of a blood vessel. Endovascular therapy is the most effective way to restore blood flow. However, despite the restoration of blood flow in some patients, their clinical prognosis often remains unsatisfactory. Albumin has shown neuroprotective effects in animal models of AIS. Therefore, this study aims to evaluate the safety, feasibility, and efficacy of local arterial infusions of 20% human serum albumin solution as an adjuvant therapy after endovascular therapy in patients with AIS.

METHODS

This study is a prospective, therapeutic exploratory, non-randomized, open-label, phase 1 clinical trial testing the use of 20% human serum albumin solution injected via the artery immediately after successful reperfusion in patients with AIS. The study is divided into two stages. In the first stage, a single-dose-finding will explore the maximum safe dose according to the 3 + 3 dose escalation principle;, with the maximum dose being 0.60 g/kg. After recanalizing the occluded blood vessel, human serum albumin solution will be injected into the internal carotid artery region through a guiding catheter for 30 min. The second stage involves an albumin adjuvant therapy cohort (AT) and an endovascular treatment lonely cohort (ET). The AT cohort will encompass at least 15 additional participants to complete safety trials at the maximum safe dose determined in the first stage. The ET cohort will include well-matched patients receiving endovascular therapy alone, derived from a contemporaneous prospective registry, who will be excluded from having cardiopulmonary disorders and from receiving any neuroprotective therapy. The primary outcome of this study will be symptomatic intracranial hemorrhage. Efficacy outcomes will include the proportion of patients with the progression of cerebral infarction volume, a modified Rankin Scale of 0-2 on day 90 after randomization. An exploratory secondary outcome will be the analysis of thromboinflammatory and neuroprotective molecule profiles.

CONCLUSION

This pilot trial aims to explore the safety and efficacy of arterial infusion of an albumin solution after occlusive vessel opening in AIS. The results will provide data parameters for subsequent tests on the arterial infusion of albumin solutions.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT05953623.

Role of Neutrophils as Therapeutic Targets in Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a major health problem. It is one of the most common types of stroke and results in mortality in approximately half of patients. More than half of the fatalities occur in the first 2 days. In addition to the mass effect after ICH hemorrhage, complex pathophysiological mechanisms such as intracranial vessel vasospasm, microthrombosis, and inflammatory immune reaction also increase brain damage. Both resident (including microglia and astrocytes) and circulating immune cells (including neutrophils, macrophages, and lymphocytes) involved in the inflammatory process. The inflammatory response is especially harmful in the acute phase due to harmful substances secreted by infiltrating immune cells. The inflammatory response also has beneficial effects, especially in the later stages. Their role in pathophysiology makes immune cells important therapeutic targets. General immunosuppressive approaches and depleting cell groups such as neutrophils or keeping them away from the lesion site may not be sufficient to prevent poor outcomes after ICH. This is most likely because they suppress anti-inflammatory activities and pro-inflammatory effects. Instead, directing immune cells to the beneficial subpopulation seems like a more rational solution. The pro-inflammatory N1 subpopulation of neutrophils damages the tissue surrounding ICH. In contrast, the N2 subpopulation is associated with anti-inflammatory reactions and tissue repair. Studies show that when neutrophils are polarized toward the N2 subpopulation, clinical outcomes improve and the volume of the infarct decreases. However, more research is still needed. This study aims to evaluate the role of neutrophils as immunotherapeutic targets in ICH in light of current knowledge.

Leptomeningeal anastomoses: Mechanisms of pial collateral remodeling in ischemic stroke

Arterial collateralization, as determined by leptomeningeal anastomoses or pial collateral vessels, is a well‐established vital player in cerebral blood flow restoration and neurological recovery from ischemic stroke. A secondary network of cerebral collateral circulation apart from the Circle of Willis, exist as remnants of arteriole development that connect the distal arteries in the pia mater. Recent interest lies in understanding the cellular and molecular adaptations that control the growth and remodeling, or arteriogenesis, of these pre‐existing collateral vessels. New findings from both animal models and human studies of ischemic stroke suggest a multi‐factorial and complex, temporospatial interplay of endothelium, immune and vessel‐associated cell interactions may work in concert to facilitate or thwart arteriogenesis. These valuable reports may provide critical insight into potential predictors of the pial collateral response in patients with large vessel occlusion and may aid in therapeutics to enhance collateral function and improve recovery from stroke.

This article is categorized under:

Neurological Diseases > Molecular and Cellular Physiology

The Protective and Reparative Role of Colony-Stimulating Factors in the Brain with Cerebral Ischemia/Reperfusion Injury

Stroke is a debilitating disease and has the ability to culminate in devastating clinical outcomes. Ischemic stroke followed by reperfusion entrains cerebral ischemia/reperfusion (I/R) injury, which is a complex pathological process and is associated with serious clinical manifestations. Therefore, the development of a robust and effective poststroke therapy is crucial. Granulocyte colony-stimulating factor (GCSF) and erythropoietin (EPO), originally discovered as hematopoietic growth factors, are versatile and have transcended beyond their traditional role of orchestrating the proliferation, differentiation, and survival of hematopoietic progenitors to one that fosters brain protection/neuroregeneration. The clinical indication regarding GCSF and EPO as an auspicious therapeutic strategy is conferred in a plethora of illnesses, including anemia and neutropenia. EPO and GCSF alleviate cerebral I/R injury through a multitude of mechanisms, involving antiapoptotic, anti-inflammatory, antioxidant, neurogenic, and angiogenic effects. Despite bolstering evidence from preclinical studies, the multiple brain protective modalities of GCSF and EPO failed to translate in clinical trials and thereby raises several questions. The present review comprehensively compiles and discusses key findings from in vitro, in vivo, and clinical data pertaining to the administration of EPO, GCSF, and other drugs, which alter levels of colony-stimulating factor (CSF) in the brain following cerebral I/R injury, and elaborates on the contributing factors, which led to the lost in translation of CSFs from bench to bedside. Any controversial findings are discussed to enable a clear overview of the role of EPO and GCSF as robust and effective candidates for poststroke therapy.

Phase I and Phase II Therapies for Acute Ischemic Stroke: An Update on Currently Studied Drugs in Clinical Research

Acute ischemic stroke is a devastating cause of death and disability, consequences of which depend on the time from ischemia onset to treatment, the affected brain region, and its size. The main targets of ischemic stroke therapy aim to restore tissue perfusion in the ischemic penumbra in order to decrease the total infarct area by maintaining blood flow. Advances in research of pathological process and pathways during acute ischemia have resulted in improvement of new treatment strategies apart from restoring perfusion. Additionally, limiting the injury severity by manipulating the molecular mechanisms during ischemia has become a promising approach, especially in animal research. The purpose of this article is to review completed and ongoing phases I and II trials for the treatment of acute ischemic stroke, reviewing studies on antithrombotic, thrombolytic, neuroprotective, and antineuroinflammatory drugs that may translate into more effective treatments.

Safety and efficacy of cell therapies administered in the acute and subacute stages after stroke: a meta-analysis

AIMS

To evaluate the safety and efficacy of cell therapies administered acutely/sub-acutely after stroke.

METHODS

Five databases were searched for studies examining the safety/efficacy of cell therapies administered ≤90 days post-stroke. Reporting quality and adherence to research guidelines were evaluated. Safety and efficacy were assessed using risk ratios/pooled incidence rates and Hedge's g, respectively.

RESULTS

11 therapies (Nstudies= 28) were trialed: reporting quality was high, but adherence to guidelines low. Serious adverse events were observed following five treatments; six improved outcomes. There was a trend toward larger treatment effects in non-blinded studies, younger participants, and higher dosages.

CONCLUSION

Although a number of therapies appear effective, many studies did not control for normal recovery (standard-care). Long-term safety also needs to be established.

Delayed application of the haematopoietic growth factors G-CSF/SCF and FL reduces neonatal excitotoxic brain injury

BACKGROUND

Developmental brain injury results in cognitive and motor deficits in the preterm infant. Enhanced glutamate release and subsequent receptor activation are major pathogenetic factors. The effect of haematopoietic growth factors, such as granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF) and flt-3 ligand (FL) on neonatal brain injury is controversially discussed. Timing of treatment is known to be a crucial factor. Based on the hypothesis that an exacerbation of injury is caused by administration of substances in the acute phase, the objective of this study was to evaluate the effect of delayed administration of G-CSF/SCF and FL to protect against excitotoxic brain injury in vivo.

METHODS

In an established neonatal mouse model of excitotoxic brain injury, we evaluated the effect of daily intraperitoneal doses of G-CSF/SCF or FL, starting 60 h after the excitotoxic insult.

RESULTS

Intraperitoneal injections of G-CSF/SCF and FL, given 60 h after the excitotoxic insult, significantly reduced lesion size at postnatal days 10, 18 and 90. G-CSF/SCF treatment resulted in a decrease in apoptotic cell death indicated by reduced caspase-3 activation. G-CSF/SCF and FL treatment did not affect apoptosis-inducing factor-dependent apoptosis or cell proliferation.

CONCLUSION

We show that delayed systemic treatment with the haematopoietic growth factors G-CSF/SCF and FL protects against N-methyl-D-aspartate receptor-mediated developmental excitotoxic brain damage. Our results suggest that neuroprotective effects in this neonatal animal model of excitotoxic brain injury depend on the timing of drug administration after the insult.

Targeting neutrophils in ischemic stroke: translational insights from experimental studies

Neutrophils have key roles in ischemic brain injury, thrombosis, and atherosclerosis. As such, neutrophils are of great interest as targets to treat and prevent ischemic stroke. After stroke, neutrophils respond rapidly promoting blood-brain barrier disruption, cerebral edema, and brain injury. A surge of neutrophil-derived reactive oxygen species, proteases, and cytokines are released as neutrophils interact with cerebral endothelium. Neutrophils also are linked to the major processes that cause ischemic stroke, thrombosis, and atherosclerosis. Thrombosis is promoted through interactions with platelets, clotting factors, and release of prothrombotic molecules. In atherosclerosis, neutrophils promote plaque formation and rupture by generating oxidized-low density lipoprotein, enhancing monocyte infiltration, and degrading the fibrous cap. In experimental studies targeting neutrophils can improve stroke. However, early human studies have been met with challenges, and suggest that selective targeting of neutrophils may be required. Several properties of neutrophil are beneficial and thus may important to preserve in patients with stroke including antimicrobial, antiinflammatory, and neuroprotective functions.

Neuroprotection after cerebral ischemia

Cerebral ischemia, a focal or global insufficiency of blood flow to the brain, can arise through multiple mechanisms, including thrombosis and arterial hemorrhage. Ischemia is a major driver of stroke, one of the leading causes of morbidity and mortality worldwide. While the general etiology of cerebral ischemia and stroke has been known for some time, the conditions have only recently been considered treatable. This report describes current research in this field seeking to fully understand the pathomechanisms underlying stroke; to characterize the brain's intrinsic injury, survival, and repair mechanisms; to identify putative drug targets as well as cell-based therapies; and to optimize the delivery of therapeutic agents to the damaged cerebral tissue.

The rise of cell therapy trials for stroke: review of published and registered studies

Stroke is the second leading cause of death and the third leading cause of disability worldwide. Approximately 16 million first-ever strokes occur each year, leading to nearly 6 million deaths. Nevertheless, currently, very few therapeutic options are available. Cell therapies have been applied successfully in different hematological diseases, and are currently being investigated for treating ischemic heart disease, with promising results. Recent preclinical studies have indicated that cell therapies may provide structural and functional benefits after stroke. However, the effects of these treatments are not yet fully understood and are the subject of continuing investigation. Meanwhile, different clinical trials for stroke, the majority of them small, nonrandomized, and uncontrolled, have been reported, and their results indicate that cell therapy seems safe and feasible in these conditions. In the last 2 years, the number of published and registered trials has dramatically increased. Here, we review the main findings available in the field, with emphasis on the clinical results. Moreover, we address some of the questions that have been raised to date, to improve future studies.