[Fc Fusion Protein as a Novel Treatment for Myasthenia Gravis].

Myasthenia gravis (MG) is an inflammatory disorder caused by autoantibodies against the nicotinic acetylcholine receptor (AChR). New therapeutic options for MG are required because the conventional treatments cannot always achieve long-term remission in MG patients. We developed a fusion protein, AChR-Fc, as a novel therapeutic agent for patients with MG. It is composed of the extracellular domain of human AChR-α1 subunit and human IgG1. AChR-Fc exhibited dual activities: it neutralized anti-AChR antibodies and demonstrated an enhanced cytotoxicity against autoantibody-producing B cells. Therefore, AChR-Fc is a novel biomolecule that can be used in the treatment of patients with MG, and potentially overcomes the disorder.