Domain Therapeutics Further Strengthens Leadership Team With Appointment of Sean A. MacDonald as Chief Business Officer

Domain Therapeutics ("Domain" or "the Company"), a clinical-stage global biopharmaceutical company developing innovative drug candidates in immuno-oncology targeting G Protein-Coupled Receptors (GPCRs), today announces the appointment of Sean A. MacDonald as its Chief Business Officer (CBO) and member of the executive management team.

In his new position, Sean will lead corporate strategy and business development bringing broad and deep expertise to steer the Company's strategic operations, as it enters its next phase of growth. With more than 20 years of senior executive experience in the life science industry, Sean has a proven, international track record of building successful biotech companies and will drive best practices amongst Domain's growing portfolio of assets and partnerships. Over the past year, Sean worked with Domain as an independent Senior Advisor, providing strategic input and support to the Company's management team.

Prior to his time with Domain, Sean played a pivotal role in multiple deals, including licensing activities, mergers and acquisitions, and fundraising and held several strategic positions in the pharmaceutical industry. This included positions such as Chief Business Officer of iOnctura, Head of Business Development for Cosmo Pharmaceuticals, President and Chief Executive Officer of Corbin Therapeutics Inc, and Vice President of Corporate and Business development at Pharmascience Inc. In addition, he currently serves as a Board Director at Edesa Biotech. Sean holds a Bachelor of Science in Molecular Biology and an MBA from the University of Ottawa.

Today's announcement follows the recent appointments of Dr. Anthony Johnson as President and Chief Executive Officer and Michael Gottlieb as Chairman of the Board of Directors, signalling Domain's accelerated focus on North American expansion as the leading GPCR immuno-oncology company.

Dr. Tony Johnson, President and Chief Executive Officer of Domain Therapeutics, said: "This is an incredible time for Domain Therapeutics, and as the Company continues to grow, I am thrilled to officially welcome Sean to the team. His deep understanding of the biothechnology sector, combined with his vast experience in executing deals at the most senior levels of business development and planning, will be a tremendous asset. As we work to expand our US market presence and build our unrivalled pipeline of GCPR targeted cancer immunotherapies, Sean's expertise will be invaluable in supporting our success."

Sean A. MacDonald, newly appointed Chief Business Officer of Domain Therapeutics, commented: "I am delighted to join Domain as Chief Business Officer at a pivotal moment as we rapidly advance our multiple drug candidates through clinical development. Over the past year advising Domain, I have seen first-hand the strength of the team, the quality and precision of the science, and the amazing potential of our innovative approach to unlock the full power of the immune system. I look forward to continuing to support the Company's growth and evolution solidifying its position as a recognized leader in its field and bringing new treatments to cancer patients worldwide."

About Domain Therapeutics : www.domaintherapeutics.com