Safety Study of Dantrolene to Treat Cerebral Vasospasm After Subarachnoid Hemorrhage

Overview

Subarachnoid hemorrhage (SAH) is a devastating acute brain injury due to bleeding onto the brain surface from a ruptured aneurysm. Cerebral vasospasm (cVSP; critical narrowing of brain arteries) is a known complication after SAH and significantly increases disability and death after SAH. Vasospasm is difficult to treat and can lead to stroke. Animal studies have shown that the muscles in the artery wall play a role in cVSP. Dantrolene has been FDA approved and extensively used in clinical practice as a muscle relaxant for more than 30 years. It has been shown to provide some benefit in animal studies of cVSP, as well as in a small number of humans. Therefore, we plan to undertake this study to evaluate the safety and tolerability of treatment with dantrolene in patients with cVSP after SAH, and to determine the maximal tolerated dose to be used in future studies to determine if treatment with Dantrolene can improve the outcome of patients with cVSP after SAH.

Our main objectives are: 1) to evaluate the safety and tolerability of varying doses of dantrolene, by determining the treatment related adverse events, in participants with cVSP after SAH; and 2) to determine the maximal tolerated dose to be adopted in subsequent studies and 3) to determine efficacy trends of dantrolene on brain vessels as assessed by ultrasound of brain vessels (transcranial Doppler). We hypothesize that dantrolene is well-tolerated and has minimal serious adverse effects in patients with cVSP after SAH. The results can potentially bring a new treatment to patients with SAH. cVPS after SAH is a frequent cause of disability and death. A successful study demonstrating the safety of dantrolene in would be of considerable public health significance.