Leadership Team

Mr. Lettmann has served as our Chief Executive Officer since September 2023 and as a member of our board of directors since April 2020. He previously served as a member of our board of directors from March 2015 to May 2017. Previously, Mr. Lettmann was a General Partner of Lightstone Ventures from March 2012 to July 2023 and a Partner at Morgenthaler Ventures, a venture capital and private equity firm, since June 2009. He previously served as Chief Executive Officer of Promedior Inc., a biotechnology company acquired by Roche, from January 2019 to February 2020 and as Vice President at Split Rock Partners, a venture capital firm, from June 2006 to June 2009. Mr. Lettmann has been a member of the board of directors of several public and privately held companies, including Ra Pharmaceuticals, a clinical-stage pharmaceutical company acquired by UCB. Mr. Lettmann holds a Bachelor of Arts degree in psychology from the University of Iowa and an MBA from the University of Michigan’s Ross School of Business.

Dr. Dillon has served as Chief Operations Officer since August 2025. She previously held the role of Chief Business Officer since joining ALX Oncology in 2024. She joined ALX Oncology from Calithera Biosciences, where she most recently served as Senior Vice President of Commercial and Portfolio Strategy. Prior to joining Calithera in 2017, Dr. Dillon served in roles of increasing responsibility across marketing, sales and pipeline commercialization at Genentech. Prior to Genentech, Dr. Dillon was a Senior Consultant at the management consulting firm Campbell Alliance. She completed a postdoctoral fellowship at the University of California, San Francisco, Howard Hughes Medical Institute, in what is now the Broad Stem Cell Center. Dr. Dillon holds a Ph.D. and Master of Science degree in neuroscience from Albert Einstein College of Medicine, and a Bachelor of Arts degree in psychology from the University of Richmond.

Ms. Pinto has served as our Senior Vice President Finance and Chief Accounting Officer since August 2023. Prior to 2023, she served as our Vice President Finance and Chief Accounting Officer since May 2021. Before joining ALX Oncology, Ms. Pinto was with Tizona Therapeutics, Inc. from July 2016 to April 2021, where she most recently served as Vice President of Finance and Operations. Prior to Tizona, Ms. Pinto was the Corporate Controller at InSite Vision Inc. from December 2008 to July 2016, the Assistant Controller at Bare Escentuals, Inc. from May 2007 to November 2008, and Director of Corporate Accounting and Financial Reporting at Dreyer’s Grand Ice Cream Holdings, Inc. from March 2002 to May 2007. Ms. Pinto started her career in the audit practice at Deloitte and Touche LLP after graduating with a Bachelor of Science degree in business administration with a major in accounting from Montana State University. She is a Certified Public Accountant.

Dr. Barbara Klencke has served as our Interim Chief Medical Officer since September 2025. She previously served as a member of the board of directors. She currently serves as an independent board director of Xencor, and TScan Therapeutics. Dr. Klencke has over 30 years of experience in patient care, academic and scientific research and clinical drug development in hematology and oncology. She has served in various executive leadership roles at a range of small, mid-sized, and large biotech companies including Sierra Oncology, Inc. (acquired by GlaxoSmithKline for $1.9B), Onyx Pharmaceuticals (acquired by Amgen for $10.4B) and Genentech, a member of the Roche Group. Prior to entering the biotechnology industry, Dr. Klencke served as an Assistant Clinical Professor of Medicine, Division of Hematology and Oncology, at the University of California, San Francisco, where she previously completed her training in hematology, oncology and internal medicine. She holds a Bachelor of Science degree from Indiana University and an M.D. from the University of California, Davis.

Harish Shantharam has served as Chief Financial Officer since January 2025. He joined ALX Oncology from CymaBay Therapeutics, Inc., where he helped guide the company in its transition towards late-stage development and commercial readiness and through its $4.3 billion acquisition by Gilead Sciences, Inc. Earlier in his career, he served in roles of increasing responsibility and scope at Gilead Sciences, including as Vice President and Head of Global Commercial Finance, where he led the financial operations supporting a global $20 to $30 billion-dollar revenue business. Prior to joining Gilead, Mr. Shantharam served in various roles of increasing responsibility driving forecasting, commercial analytics and business development at Amgen. Mr. Shantharam holds an MBA in finance from UCLA Anderson School of Management and a graduate degree in Industrial Engineering from the University of Texas at Arlington. He is also a CFA charter holder.