Certain Restricted Stock Units of Adamas Pharmaceuticals, Inc. are subject to a Lock-Up Agreement Ending on 26-MAY-2021. These Restricted Stock Units will be under lockup for 91 days starting from 24-FEB-2021 to 26-MAY-2021. Details: The executive officers and directors, in their individual capacity, have agreed not to sell or transfer any common stock or securities convertible into or exchangeable or exercisable for common stock, for 90 days after the date of this prospectus supplement without first obtaining the written consent of SVB Leerink LLC and William Blair & Company, L.L.C. on behalf of the underwriters.