SAN DIEGO--(BUSINESS WIRE)--ACADIA Pharmaceuticals Inc. (Nasdaq:ACAD), a biopharmaceutical company utilizing innovative technology to fuel drug discovery and clinical development of novel treatments for central nervous system disorders, today announced that it has expanded and further strengthened the intellectual property portfolio for its serotonin platform by entering into an agreement to license certain intellectual property rights from Ipsen (Euronext:IPN), an innovation driven international specialty pharmaceutical group.