Clinical Trials in Acute CNS Injuries

Acute central nervous system injuries include head injury, spinal cord injury, focal and global cerebral ischemia and subarachnoid hemorrhage (SAH). Our paper focuses on brain injury and on SAH. Trauma is the first cause of death below the age of 45 in many countries all over the world (1); head injury contributes in the vast majority of cases. An average of 200 patients per 100.000 population per year are admitted to the hospital following a head injury. About 20 per 100.000 population per year are the deaths related to the brain injury (1). Many cases among the survivors present neurological sequelae leading to severe disability. SAH is less frequent (11 cases per 100.000 inhabitants per year); mortahty and morbidity in this disease are mainly related to the occurrence of vasospasm (40% to 60% of patients) (2). Both in brain injury and in SAH patients there is primary brain damage due to mechanical factors in head injuries and to hemorrhagic stroke in SAH. This primary damage is followed by secondary damage due to biochemical processes in the tissue surrounding the primary injury. Secondary ischemia, which is present both following brain injury and during vasospasm, leads to loss or reduction of blood flow and oxygen supply. With the improvement in our knowledge concerning this biochemically induced damage, a new set of drugs has been tested in animal models. A few of these drugs reached a phase II — III clinical trial both in SAH and in brain injured patients.