Press Release Details

Cambridge, MA and Gosselies, Belgium – June 1, 2020 – iTeos Therapeutics, a clinical-stage biopharmaceutical company pioneering the discovery and development of a new generation of highly differentiated immuno-oncology therapeutics for patients, announced today the appointment of Ann D. Rhoads to its Board of Directors. Ms. Rhoads brings over 25 years of corporate and financial expertise in the life sciences and healthcare industry.

"I am delighted to welcome Ann to our Board of Directors at a transformational point in the company’s history. Having recently completed our $125 million Series B-2 financing with a strong investor syndicate, we are now poised to progress the clinical development of our two highly innovative oncology pipeline programs, an adenosine A_2A receptor antagonist, EOS-850, and an anti-TIGIT antibody, EOS-448," said David Hallal, Chairman of the iTeos Therapeutics Board. "Ann is a proven leader and brings ideal expertise to our Board. I look forward to working with her and our other Directors to collaborate with the management team as they seek to drive the development of therapies that have the potential to transform the lives of patients suffering with cancer.”

“Ann has an impressive track record in executive management in our industry, specifically in the immuno-oncology space; her extensive experience will be instrumental to us as we continue on our growth trajectory. I am thrilled to welcome her to the Board and to draw from her expertise,” added Michel Detheux, PhD, President and Chief Executive Officer of iTeos Therapeutics.

Ms. Rhoads most recently served as the Chief Financial Officer at Forty Seven, Inc., a clinical stage immuno-oncology company, from 2018 until its sale to Gilead in 2020. During her tenure at Forty Seven, Inc., it completed an initial public offering and two subsequent public equity financings. From 2010 to early 2017, she was Executive Vice President and Chief Financial Officer at Zogenix, Inc. where she oversaw all areas of financial management, including the company’s initial public offering and subsequent public equity and debt financings. Prior to joining Zogenix in 2010, Ms. Rhoads was Senior Vice President and Chief Financial Officer of the healthcare improvement company Premier, Inc.. Ms. Rhoads started her career as an investment professional with Merrill Lynch and the Sprout Group, the venture capital affiliate of Donaldson, Lufkin & Jenrette (now part of Credit Suisse). Ms. Rhoads holds an M.B.A. from Harvard Business School and a B.S. in Business Administration with a focus on Finance from the University of Arkansas.

"iTeos is progressing two innovative immunotherapy candidates through the clinic, both of which are highly differentiated from other programs in clinical development," commented Ann Rhoads. "I look forward to working with the management team and Board of Directors to help iTeos advance its financial and business objectives using the knowledge and experience I have gained during my career."

About iTeos Therapeutics

iTeos is a clinical-stage biopharmaceutical company pioneering the discovery and development of a new generation of highly differentiated immuno-oncology therapeutics for patients. iTeos leverages its deep understanding of the tumor microenvironment and immunosuppressive pathways to design novel product candidates with an aim to improve the clinical benefit of oncology therapies. The innovative pipeline includes two clinical-stage programs targeting novel, validated immuno-oncology pathways designed to build on prior learnings in the field to have differentiated pharmacological and clinical profiles. The most advanced product candidate, EOS-850, is designed as a highly selective small molecule antagonist of the adenosine A2a receptor, in the adenosine triphosphate adenosine pathway, a key driver of immunosuppression in the tumor microenvironment across a broad range of tumors. EOS-850 is investigated in an open-label Phase 1/2a clinical trial in adult patients with advanced solid tumors and encouraging preliminary single-agent activity were observed in the dose escalation portion of the trial. The lead antibody product candidate, EOS-448, is an antagonist of TIGIT, or T-cell immunoreceptor with Ig and ITIM domains, a checkpoint that has a role in both inhibitory and stimulatory pathways in the immune system. EOS-448 was also designed to engage the Fc gamma receptor, or FcgR, to promote antibody-dependent cellular cytotoxicity, or ADCC, activity, including the elimination of tumor-infiltrating regulatory T cells, or Tregs. An open-label Phase 1/2a clinical trial of EOS-448 was recently initiated in adult patients with advanced solid tumors. The Company recently closed a $125 million Series B-2 financing from leading biotech investors including RA Capital, Boxer Capital, MPM Capital, Janus Henderson Advisors, RTW Investments, Invus, HBM Partners, Fund+, Vives II, SRIW and SFPI. iTeos Therapeutics is headquartered in Cambridge, MA with a research center in Gosselies, Belgium. For more information, please visit www.iteostherapeutics.com.

For further information, please contact:

Michel Detheux, CEO

iTeos Therapeutics Inc

info@iteostherapeutics.com

Amber Fennell, Paul Kidwell

Consilium Strategic Communications

+44 203 709 5700

iteos@consilium-comms.com

Sarah McCabe and Zofia Mita

Stern Investor Relations, Inc.

+ 1 212 362 1200

iTeos@sternir.com