On February 13, 2019, Geert Cauwenbergh, Dr. Med. Sc., informed the Board of Directors intends to retire as principal executive and financial officer (the "CEO") of Phio Pharmaceuticals Corp. effective March 1, 2019.

Dr. Cauwenbergh's announced retirement was not due to any disagreements with the Company. Indeed, Dr. Cauwenbergh will remain on the Board and support the transition to the new CEO. On February 13, 2019, the Company's Board appointed Gerrit Dispersyn, Dr. Med.

Sc., currently President and Chief Operating Officer ("COO") of the Company, as the Company's CEO (including its principal financial officer) effective March 1, 2019 for a term to expire at such time as his successor is appointed and qualified. Dr. Dispersyn will remain President, but will resign as COO as of March 1, 2019. The Board does not intend appoint a successor COO at this time.

Dr. Dispersyn joined the Company on April 24, 2017, as its Chief Development Officer, before becoming the company's President and COO on November 14, 2018.