APLS 2018 Proxy Statement

Nominees for Election as Class I Director Biographical information as of April 23, 2018, including principal occupation and business experience during the last five years, for our nominee for election as the class I director at our Annual Meeting is set forth below. Class I Director Nominee Age Stephanie Monaghan O’Brien has served as a member of our board of directors since July 2013. Ms. O’Brien has been a member of the investment team at Morningside since 1997. She has served as a director of Aduro Biotech Inc., a publicly-traded company, since 2011, and as a director of numerous private nonclinical and clinical-stage companies developing drugs across a broad spectrum of therapeutic focus, including oncology and immunotherapy, and has extensive experience providing operational and management oversight to venture-backed technology companies. She has also facilitated multiple financings for public and private companies such as Dendreon Corporation, BioVex Group, Inc., Stealth Biotherapeutics Inc. and Sohu.com. Prior to joining Morningside, Ms. O’Brien spent nine years as a corporate lawyer with Hale and Dorr in its Boston and Washington, D.C. offices, working primarily on public offerings, venture capital finances and start-up companies. She previously worked at Chase Manhattan Bank, working in international portfolio analysis. She received her A.B., cum laude, from Harvard College and her J.D. from New York University School of Law. We believe that Ms. O’Brien is qualified to serve on our board of directors because of her strong background working with biotechnology companies and her extensive experience serving on the boards of both public and private companies. 59 The proxies will be voted in favor of Ms. O’Brien unless a contrary specification is made in the proxy. Ms. O’Brien has consented to serve as a director if elected. However, if she is unable for any reason to serve as a director, proxies may be voted for a substitute who will be designated by our board of directors. The board of directors recommends voting “FOR” the election of Stephanie Monaghan O’Brien as the class I director for a three-year term ending at the annual meeting of stockholders to be held in 2021 . Directors Continuing in Office Biographical information as of April 23, 2018, including principal occupation and business experience during the last five years, for our directors continuing in office after the Annual Meeting is set forth below. Class II Directors (Term Expires at 2019 Annual Meeting) Age A. Sinclair Dunlop has served as a member of our board of directors since March 2010. Mr. Dunlop is a co-founder of venture capital fund Epidarex Capital, and has served as the Managing Partner since July 2010. Since 2005, Mr. Dunlop has served as the Managing Partner of venture capital fund Masa Life Science Ventures, LP. Mr. Dunlop currently serves on the board of directors of several private companies, including Potentia. Mr. Dunlop received his M.B.A. from Columbia Business School where he was the R.C. Kopf British-American Fellow in international business. He also received an M.A. with Honors in political economy from the University of Glasgow and an M.A. in international relations from the Maxwell School of Citizenship and Public Affairs at Syracuse University. We believe that Mr. Dunlop is qualified to serve on our board of directors because of his extensive investment and business experience. 46 - 7 -