2,300,000 Common Stock of Aclaris Therapeutics, Inc. are subject to a Lock-Up Agreement Ending on 16-JAN-2017. These Common Stock will be under lockup for 60 days starting from 17-NOV-2016 to 16-JAN-2017. Details: The company directors and executive officers have agreed that, they will not without the prior written consent of Jefferies LLC and Leerink Partners LLC, sell, offer to sell, contract to sell or lend any shares or related securities, affect any short sale, for a period of 90 days after the date of this prospectus supplement. One of the stockholders, Sofinnova Venture Partners VIII, L.P., has agreed to this restriction for a period of 60 days.