rHIgM22 is a remyelinating antibody being studied for the treatment of multiple sclerosis (MS). In April 2015, Acorda presented data from its first Phase 1 clinical trial of rHIgM22. Safety data showed it was well-tolerated in each of the five tested doses, supporting additional clinical development. In addition, testing detected rHIgM22 in cerebrospinal fluid, indicating the drug’s access to the central nervous system. These data were presented at the 67th American Academy of Neurology Annual Meeting.
Acorda has completed and analyzed data from another Phase 1 trial using one of two doses of rHIgM22 or placebo in 27 people with MS who experienced an acute relapse. Data from the trial showed that a single dose of rHIgM22 was not associated with any safety signals. The trial’s primary objectives were safety and tolerability of a single dose following a relapse. The study was not powered to show efficacy and exploratory measures showed no difference between the treatment groups. The company is considering next steps for the program.
MS is a chronic, usually progressive disease in which a person’s own immune system attacks and degrades the function of nerve fibers in the brain and spinal cord by destroying myelin (a process known as demyelination) and eventually the nerve fibers themselves. Myelin is a fatty layer of membranes that insulates nerves, facilitating the transmission of electrical impulses through nerve pathways that control neurological function.
The cells that make myelin, called oligodendrocytes, can initially repair myelin, but as MS progresses, there is little spontaneous repair. While current standard of care aims to slow the progression of the disease, there are no approved therapies that stimulate the repair or regrowth of myelin once it has been damaged in demyelinating diseases such as MS. If myelin is able to be repaired, it could restore electrical conduction and may serve to protect the exposed nerve fiber from further damage.
Preclinical studies have found that rHIgM22 promoted remyelination by stimulating oligodendrocytes to repair areas of demyelination. Preclinical studies with rHIgM22 also resulted in sustained improvements in motor activity.
Acorda and the Mayo Foundation for Medical Education and Research have been collaborating on the remyelinating antibody program since 1995.