Inebilizumab is a humanised monoclonal antibody that is in clinical development for reducing the risk of an attack in patients with Neuromyelitis Optica Spectrum Disorders (NMOSD). NMOSD, previously known as NMO and as Devic’s disease, is a rare, disabling autoimmune disease of the central nervous system. It predominantly affects the optic nerve and spinal cord, however involvement of the brain can occur. Patients with NMOSD present with acute, often severe attacks that lead to blindness, limb weakness or paralysis, difficulty controlling the bladder or bowels, fatigue, pain, and other manifestations.
The main objective of current treatments is to reduce the rate of acute NMOSD attacks. This is the most important goal in treating these patients. There are no approved attack-preventing therapies and different off label immunosuppression medications are being used with low level of evidence for efficacy. Inebilizumab is an experimental therapy that specifically targets B lymphocytes which are the source of the pathogenic auto antibody in this disease, the AQP4-IgG. Depleting B cells by Inebilizumab will potentially reduce risk of NMOSD attack. Inebilizumab binds to and depletes CD19+ B-cells including plasmablasts and plasma cells. These CD19+ plasmablasts are the type of B cells that produce the AQP4-IgG which in turn acts against a key water channel protein expressed on astrocytes in the central nervous system. If licensed, inebilizumab may offer a first line disease-modifying treatment option for patients with NMOSD.
Fenfluramine belongs to a class of drugs called the selective serotonin releasing agonists which stimulates multiple 5-HT receptor sub-types through the release of serotonin. Fenfluramine may also act on other receptors and these actions may help to reduce the frequency of seizures. When added to other standard anti-epileptic treatments, fenfluramine hydrochloride has shown preliminary evidence of reducing seizure frequency. If licensed, fenfluramine hydrochloride may offer an additional treatment option for patients with Lennox-Gastaut syndrome.