Guillain Barré syndrome (GBS)
Guillain Barré syndrome is an acute immune-mediated polyneuropathy where the immune system is triggered into attacking the myelin sheath surrounding nerves, leading to progressive, fairly symmetric muscle weakness accompanied by absent or depressed deep tendon reflexes. Patients usually present a few days to a week after onset of symptoms. The weakness can vary from mild difficulty with walking to nearly complete paralysis of all extremities, facial, respiratory, and bulbar muscles.
Guillain-Barré syndrome occurs worldwide, with an overall incidence of one to two per 100,000 per year, and over 6,000 patients admitted to US hospitals with a primary diagnosis of GBS every year. While all age groups are affected, the incidence increases by approximately 20 percent with every ten-year increase in age beyond the first decade of life. Patients are treated with supportive care, plasma exchange or Intravenous Immunoglobulin (IVIG).
The proportion of patients with GBS who walk independently at six months and one year after diagnosis is approximately 80 and 84 percent, respectively. At one year, full recovery of motor strength occurs in about 60 percent of patients, while severe motor problems persist in about 14 percent. Approximately five to ten percent of patients with GBS have a prolonged course with several months of ventilator dependency and very delayed and incomplete recovery. Within one year of diagnosis, approximately 4 to 5 percent of patients with GBS die despite intensive care.
Nomacopan has been successfully tested in animal models of Guillain Barré syndrome (GBS). In GBS, complement-mediated damage is provoked by the deposition of auto-antibodies, against the neuromuscular junction in the myelin sheath. This in turn triggers systemic complement activation and local tissue destruction, with often devastating neurological consequences.