On August 21, 2019, Christopher A. Viehbacher tendered his resignation from the Board of Axcella Health Inc., effective immediately. After four years on the Board, Mr. Viehbacher has decided to step down from the Board given increased time commitments related to the growth of the investment fund he manages. Mr. Viehbacher did not serve on any of the committees of the Board.

On August 21, 2019, upon the recommendation of its Nominating and Corporate Governance Committee, the Board appointed Catherine A. Sohn, Pharm. D. to join the Board, effective immediately. The Board determined that Dr. Sohn is independent under the listing standards of Nasdaq and the Company's corporate governance guidelines.

Dr. Sohn will serve as a Class III director with a term expiring at the annual meeting of stockholders to be held in 2022. The members of the Company's Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee remain the same as Dr. Sohn has not been appointed to any such committees at this time. On August 21, 2019, Thomas Leggett, the Senior Vice President of Finance and Chief Financial Officer of the Company, submitted notice to the Company of his resignation, effective August 30, 2019, to pursue other opportunities.

On August 21, 2019, the Board appointed, upon the effectiveness of Mr. Leggett's resignation, Shane Maltbie, Vice President, Corporate Finance, as the Company's Interim Principal Accounting Officer. Mr. Maltbie (age 38) joined the Company in 2015. Prior to joining the Company, he led the SEC reporting and technical accounting groups as the Director of Technical Accounting at PAREXEL International.

Prior to PAREXEL, Mr. Maltbie was a senior manager at Deloitte & Touche.