Assess the Safety and Efficacy of Sovateltide in Patients With Acute Cerebral Ischemic Stroke

A stroke is a syndrome defined as an abrupt neurological outburst due to impaired blood flow to part of the brain. There are two types of stroke: hemorrhagic stroke and ischemic stroke. A hemorrhagic stroke follows the rupture of a weakened blood vessel in the brain causing accumulation of blood and compression of the surrounding brain tissue. An ischemic stroke follows a blocked blood vessel by a thrombus (blood clot) or embolism. In both types of strokes, the specific region of the brain supplied by the affected blood vessel is deprived of oxygenated blood, causing local hypoxia that damages the brain tissue and cells. Both types of stroke are very serious, however ischemic stroke is more common.

The global burden of ischemic stroke is nearly 4-fold greater than hemorrhagic stroke with close to 87% of the total incidence of stroke attributed to acute cerebral ischemic stroke (ACIS). ACIS is a critical care emergency caused by a significant reduction in blood flow to the brain by a blood clot or embolism. This nearly halts cerebral blood flow to the affected region leading to neuronal death. Neuronal cell death is followed by plasma membrane disruption, swelling of organelles, leaking of cell contents into extracellular space, and loss of neuronal function. Other events that take place include inflammation, excitotoxicity, free radical mediated toxicity, cytokine mediated cytotoxicity, impaired blood-brain-barrier, and oxidative stress.

Therapeutic management of ACIS is a multidisciplinary approach with a primary goal of revascularization and limiting neuronal injury. A stroke team consists of emergency medicine physicians, neurologists/neurosurgeons, radiologists, nurses and advanced care providers, clinical pharmacists, therapists, technicians, and laboratory personnel. Currently, the only FDA-approved pharmacological agent for ischemic stroke is tissue plasminogen activator (t-PA). It is a thrombolytic agent which restores blood flow by breaking down a clot. However, timing is crucial in administration of t-PA as the therapeutic time window is very narrow and the patient must receive it within 4.5 hours of onset of stroke symptoms. Therapeutic administration after this timeframe can result in hemorrhagic transformation, leading to additional brain damage. Nevertheless, even upon timely administration of t-PA in ACIS, only about 30% of patients obtain stroke resolution having minimal or no disability at the 90-day mark.

Sovateltide (PMZ-1620, IRL-1620) is a highly selective ETB receptor agonist and a synthetic analog of ET-1. Studies conducted to determine the effects brought about by sovateltide upon its interaction with neural ETB receptors and have found that it enhances angiogenesis and neurogenesis as well as promotes neural repair and regeneration. In a rat model of ischemic stroke, sovateltide was found to be neuroprotective as well as enhance angiogenic and neurogenic remodeling. Sovateltide significantly improved survival, reduced neurological and motor function deficit, while effectively decreasing infarct volume, edema, and oxidative stress.

Sovateltide was also found to be safe and well tolerated in healthy human volunteers in a phase I clinical trial (CTRI/2016/11/007509). A phase II study was also conducted in patients with acute ischemic stroke where sovateltide demonstrated significant improvement when compared to standard of care (CTRI/2017/11/010654, NCT04046484). A recent phase III study conducted in patients of acute ischemic stroke demonstrated improved favorable functional and neurological outcome at 3 months compared to standard of care (CTRI/2019/09/021373, NCT04047563).

Clinical phase II and III results indicate that sovateltide is a first-in-class neuronal progenitor cell therapeutic that promotes quick recovery and significantly improves neurological outcomes in cerebral ischemic stroke patients. With this convincing evidence, the plan is to conduct a multicentric, randomized, double-blind, parallel, placebo-controlled phase III clinical study in the United States, Canada, United Kingdom and Europe (the demographics and standard of treatment being similar in these countries) to further assess the safety and efficacy of sovateltide in patients with acute cerebral ischemic stroke.