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ОглавлениеClinical Trials Outside the United States: Cerebral Palsy
Clinical Trials Outside the United States: Cerebral Palsy
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Clinical Trials Outside the United States: Cerebral Palsy
Cerebral palsy (CP) is the broad heterogeneous term used for a group of permanent, nonprogressive movement disorders that cause varying degrees of physical disability that typically involve body movement variations. Individuals with cerebral palsy also may experience variations in sensations, communication deficits, difficulties with depth perception, cognitive alterations, learning disabilities, behavioral problems, and seizure disorders. There are subtypes of CP that are characterized by the type of impairment. The different types include spastic, ataxic, athetoid/dyskinetic, and mixed. The majority of individuals have spastic CP. Cerebral palsy is the most commonly occurring motor disability in childhood.
CP is caused by a variety of factors, including infection in pregnancy, hypoxia during birth, severe neonatal jaundice, Rh incompatibility, or genetic factors. CP is more common in male infants and African Americans. In the United States, 800,000 individuals are diagnosed with CP, with an additional 10,000 babies diagnosed annually. Cerebral palsy is estimated to be five to 10 more times likely in poor and middle-income countries.
According to the Cerebral Palsy International Research Foundation, CP research should be focused in one of the following areas: prevention, improvement of motor and cognitive abilities in children using transformational technologies, and prevention of secondary complications and improvement in the quality of life in adults with CP. International research endeavors should focus in these key identified areas.
According to the National Institutes of Health Clinical Trials Registry (2014), there are currently 465 listed clinical trials, including current research, completed research, terminated studies, and unverified status studies, in the database. Of these, 193 active, open clinical trials examining various treatments and symptom management techniques for cerebral palsy are currently being conducted worldwide. The majority of research on CP is being conducted in the United States (211 studies) and Europe (115 studies). Other foreign countries make up the remainder of the studies, with 50 in east Asia currently or previously conducted; 36 in the Middle East; 26 in Canada; and less than 6 per region or country being conducted in Africa, Mexico, south Asia, southeast Asia, South America, Pacifica, and north Asia. Clinical trials outside the United States concentrate on a variety of issues related to cerebral palsy, its symptoms, management, treatment, and potential cures (Table 1).
The use of stem cell transplants for cerebral palsy outside the United States has been performed in other counties despite a scientific gap in the literature on the safe use of stem cells for this purpose. Clinical trials have been conducted outside the United States to determine the safety, use, advantages, and disadvantages of stem cell use for treating CP. Previously, researchers in Mexico gave subjects granulocyte colony stimulating factor (G-CSF) in an attempt to stimulate bone marrow production of stem cells. Bone marrow was then harvested, and CD 34+ cells were purified and delivered via the intrathecal route. The result of this research has not been published.
Australia recently started its first clinical trial using stem cell transplantation. The United States currently has three clinical trials exploring the use of umbilical cord blood and stem cell transplantation for children with CP. The first U.S. clinical trial using sibling umbilical cord blood began recruiting participants in 2014. In 2012, a team of researchers from South Korea conducted a randomized, placebo-controlled, double-blind clinical trial to determine whether children receiving intensive physical therapy, umbilical cord stem cell transplantation, and the hormone erythropoietin (which is used to stimulate stem cell growth) resulted in higher cognitive and physical functioning scores than children who received only erythropoietin and physical therapy or those that only underwent intensive physical therapy.
Table 1
Sources: National Institutes of Health Clinical Trials Registry (2014). Clinical trials registry. Retrieved from http://clinicaltrials.gov and Cerebral Palsy International Research Foundation (2014). New research FY 2014. Retrieved from http://cpirf.org/research/active-projects.
The transplantation of cord blood stem cells is currently available in other countries as a treatment modality for CP despite opposition from the scientific community. Because the science of cord blood transplantation is a relatively new science with emerging results in human clinical trials, multiple CP organizations have formally advised against the procedure until safety of the treatment can be verified through the scientific process. Researchers agree that stem cell transplantation, particularly through allogeneic or sibling cord blood, seems to hold the greatest hope for a partial cure or improvement of functioning.
While advances in science create excitement for future treatment modalities, it should be weighed that stem cell therapy is not without risks. Side effects from stem cell therapy transplantations have included recipient-to-host graft disease, including encephalopathy due to infection, organ failure, medication reaction, seizures, acute disseminated encephalomyelitis, thrombotic thrombocytopenic purpura, or stroke. Although adult stem cell transplants have reportedly been performed in large numbers for individuals with CP outside the United States with no reported adverse outcomes, the lack of quality clinical trials and published research does not support advocating these interventions.
Michele Davidson
George Mason University
See Also: Adult Stem Cells: Overview; Cord Blood Stem Cells.
Further Readings
Carroll, J. E. and R. W. Mays. “Update on Stem Cell Therapy for Cerebral Palsy.” Expert Opinion on Biological Therapies, v.11/4 (2011).
Centers for Disease Control and Prevention. “Data and Statistics for Cerebral Palsy” (2014). http://www.cdc.gov/ncbddd/cp/data.html (Accessed April 2014).
Cerebral Palsy International Research Foundation. “New Research FY 2014.” http://cpirf.org/research/active-projects (Accessed April 2014).
Morris, C. and D. Condie. Recent Developments in Healthcare for Cerebral Palsy: Implications and Opportunities for Orthotics. Brussels: International Society for Prosthetics and Orthotics, 2008.
National Institutes of Health, Clinical Trials Registry. “Clinical Trials Registry.” http://clinicaltrials.gov (Accessed April 2014).
