As of Q2 2024, Annexon is advancing global registrational programs for two candidates in Guillain-Barré syndrome and geographic atrophy.

The company's lead candidate, ANX005, is a a humanized IgG4 monoclonal antibody that binds with high affinity to the complement C1q protein and inhibits initiation of the classical complement cascade. The antibody is in development to treat autoimmune and neurodegenerative disorders, and has been granted Fast Track and Orphan Drug Designations from the FDA. It has also been granted Orphan Drug Designation by the European Medicines Agency (EMA).