Orphan designation for AstraZeneca's MEDI-551

Anglo-Swedish pharma major AstraZeneca and its biologics R&D arm, MedImmune, have been granted Orphan drug designation by the US Food and Drug Administration for the investigational anti-CD19 monoclonal antibody, MEDI-551, for the treatment of patients with neuromyelitis optica (NMO) as well as neuromyelitis optica spectrum disorders (NMOSD).

Developed by MedImmune, MEDI-551 is currently in Phase IIb clinical development for NMO. US drugmaker Alexion Pharmaceuticals (Nasdaq: ALXN) is also testing its already marketed Soliris (eculizumab) as a potential treatment for NMO.

NMO is a rare, life-threatening autoimmune disease of the central nervous system in which the body’s immune system attacks healthy cells, most commonly in the optic nerves and spinal cord, resulting in severe damage. NMO causes severe muscle weakness and paralysis, loss of vision, respiratory failure, problems with bowel and bladder function and neuropathic pain.  There is currently no cure or approved medicine for NMO, which affects about five in 100,000 people.