There are many areas of unmet medical need across the planet, but stroke is arguably one of the most debilitating traumas for which an efficient, effective treatment is currently lacking. The reality is that traditional drugs are not the answer for the roughly 2 million people each year in the United States, Europe and Japan that suffer an ischemic stroke (which is caused by a clot that blocks the flow of blood to the brain). Many people feel regenerative medicine holds the greatest promise to change the landscape of stroke care as we know it today, because unlike the pharmaceutical based approaches that have failed to have an impact, cell therapies are living entities that have shown the potential to repair the damage in a dynamic and multifaceted way.
On October 2nd, 2012 Athersys, Inc. (NASDAQ: ATHX), a clinical stage biotechnology company developing its MultiStem® cell therapy product and operating in the same industry as peers Cytori Therapeutics (NASDAQ: CYTX) and Osiris Therapeutics (NASDAQ:OSIR), delivered promising news for stroke victims and the regenerative medicine sector in general. While MultiStem®, a patented, adult-derived stem cell product platform, is in human trials for multiple indications, Athersys reported that it received the “go ahead” from an independent clinical safety committee to advance its mid-stage trial in ischemic stroke patients, after the initial phase of the study showed that both lower and high doses were safe and well-tolerated.
ATHX recently completed enrollment of the first two patient groups of its Phase 2 study of MultiStem(R), a novel adult stem cell therapy being developed by Athersys, administered to patients within approximately 1 to 2 days after they have experienced an ischemic stroke. The independent safety committee reviewed data from these patients, finding that both of the doses evaluated were safe and well tolerated, and therefore, recommended proceeding with high dose administration to patients for the remainder of the trial.
The Phase 2 study is a double blind, placebo-controlled trial evaluating the safety and efficacy of MultiStem when administered to patients who have suffered a moderate to moderately severe stroke, as defined by a National Institutes of Health Stroke Scale (NIHSS) score of 8 to 20. Patients enrolled in the study receive a single intravenous dose of MultiStem therapy or placebo in the 24 to 36 hours following the stroke, which is a significant extension of the current treatment window over existing standard of care. The study is currently being conducted at multiple centers throughout the United States.
“We are very excited about the initial results from this program and believe that it could represent a major advance in clinical care for ischemic stroke patients. We believe MultiStem has the potential to significantly enhance patient recovery, as well as meaningfully extend the treatment window over the current standard of care for stroke victims, enabling many more patients to receive treatment,” said Dr. Gil Van Bokkelen, Chairman and Chief Executive Officer of Athersys. “We are pleased with the results from the initial phase of the study, including the additional evidence of a consistent safety profile for MultiStem, and we intend to move the program forward aggressively to completion.”
The first part of the Phase 2 study included two cohorts, with each cohort including a placebo group and a treatment group — a low dose of MultiStem in the first cohort and a higher dose in the second cohort. The third cohort has a placebo group and treatment group, which will be evenly randomized. The study is expected to enroll approximately 136 patients in total.
Primary safety endpoints for the trial include measuring acute infusional reactions over the first 7 days following treatment. Primary efficacy measures include determining the proportion of patients with a modified Rankin Scale of 0 to 2 (which represents patients capable of independent living) at day 90 in the MultiStem treatment group compared to subjects in the placebo treatment group. Secondary endpoints include functional outcome as determined by NIHSS score and Barthel Index. The study includes additional exploratory endpoints, such as measuring stroke infarct size and blood marker changes between the MultiStem and placebo treatment groups.
“We believe that development of a safe and effective therapy for ischemic stroke represents both a major clinical and commercial opportunity, and one that could drive value for our shareholders,” added Dr. Van Bokkelen. “We believe that this Phase 2 study will provide compelling evidence of the potential of the program.”
According to the American Heart Association, approximately 800,000 individuals suffer a stroke each year in the United States, and an estimated 2 million individuals suffer a stroke each year in the United States, Japan and major European countries, combined. Given the current lack of effective therapies, many patients who suffer a stroke experience long term disability and require extensive physical therapy or experience significant or permanent disability, and as a result, must receive long-term institutional care or be cared for by a family member.
Approximately 85% of strokes are ischemic, meaning they are caused by a blockage of blood flow in the brain, which occurs as a result of a clot or “thrombus.” Currently, there is only one FDA-approved drug therapy for the treatment of ischemic stroke, the thrombolytic tPA, which helps to dissolve the blood clot that impedes blood flow in the brain. However, tPA must be administered within three to four hours from when the stroke has occurred in order to be effective. Due to its limited window, only a small percentage of all patients who could potentially benefit from therapy with tPA actually receive treatment.
As a consequence of an aging population, recent forecasts from the American Heart Association project that the prevalence of stroke will increase by 25% in the next twenty years, and the total estimated annual cost for treating and caring for stroke survivors in the United States will skyrocket from $64 billion in 2010 to $140 billion in 2030, representing a substantial increase in costs to the healthcare system. The company believes that the market for a safe and effective therapy for stroke that could be administered within a clinically reasonable time frame could represent a $15 to 20 billion annual market opportunity.
MultiStem(R) cell therapy is a patented product that has shown the ability to promote tissue repair and healing in a variety of ways, such as through the production of multiple therapeutic factors produced in response to signals of inflammation and tissue damage. MultiStem has demonstrated therapeutic potential for the treatment of inflammatory and immune disorders, neurological conditions, and cardiovascular disease, as well as other areas, and represents a unique “off-the-shelf” stem cell product that can be manufactured in a scalable manner, may be stored for years in frozen form, and is administered without tissue matching or the need for immune suppression. The product is extensively characterized for safety, consistency and potency. Athersys has forged strategic partnerships with Pfizer Inc. to develop MultiStem for inflammatory bowel disease and with RTI Biologics, Inc. to develop cell therapy for use with a bone allograft product in the orthopedic market.
Athersys is a clinical stage biotechnology company engaged in the discovery and development of therapeutic product candidates designed to extend and enhance the quality of human life. The Company is developing its MultiStem(R) cell therapy product, a patented, adult-derived “off-the-shelf” stem cell product platform for disease indications in the cardiovascular, neurological, inflammatory and immune disease areas. The Company currently has several clinical stage programs involving MultiStem, including for treating inflammatory bowel disease, ischemic stroke, damage caused by myocardial infarction, and for the prevention of graft versus host disease. Athersys has also developed a diverse portfolio that includes other technologies and product development opportunities, and has forged strategic partnerships and collaborations with leading pharmaceutical and biotechnology companies, as well as world-renowned research institutions in the United States and Europe to further develop its platform and products. More information is available at www.athersys.com.