Effective as of June 11, 2018, NantKwest, Inc. appointed Sonja Nelson as its Chief Financial Officer. In addition, Ms. Nelson will serve as Principal Financial Officer. Ms. Nelson served as Chief Accounting Officer from May 2016 to June 2018 and served as VP/Corporate Controller from November 2015 to June 2018.

Effective as of June 11, 2018, Richard Tajak has stepped down from being Chief Financial Officer although he will continue to assist on various financial and accounting matters on a consulting basis.