Item 4.01. Changes in Registrant’s Certifying Accountant.

(a) On July 17, 2020, the Audit Committee of the Board of Directors (the “Audit Committee”), of Forte Biosciences, Inc. (the “Company”) approved the dismissal of Ernst & Young LLP as the Company’s independent registered public accounting firm, effective as of July 17, 2020.

As previously reported, on June 15, 2020, the Company (formerly known as Tocagen Inc.) and privately-held Forte Subsidiary, Inc. (formerly known as Forte Biosciences, Inc.) (“Forte Subsidiary”), completed the business combination in accordance with the terms of the Agreement and Plan of Merger and Reorganization, dated February 19, 2020, as amended by that certain amendment dated May 11, 2020, by and among the Company, Telluride Merger Sub, Inc. (“Merger Sub”), and Forte Subsidiary (the “Merger Agreement”), pursuant to which Merger Sub merged with and into Forte Subsidiary, with Forte surviving as a wholly owned subsidiary of the Company (the “Merger”). Prior to the completion of the Merger, Ernst & Young LLP served as the independent registered public accounting firm of the Company.

The reports of Ernst & Young LLP on the Company’s financial statements for the years ended December 31, 2019 and 2018 did not contain an adverse opinion or disclaimer of opinion, nor were they qualified or modified as to uncertainty, audit scope, or accounting principles. During the years ended December 31, 2019 and 2018, there were no: (1) disagreements (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) between the Company and Ernst & Young LLP on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedures, which disagreement if not resolved to the satisfaction of Ernst & Young LLP would have caused Ernst & Young LLP to make reference thereto in its reports on the financial statements for such years, or (2) reportable events (as described in Item 304(a)(1)(v) of Regulation S-K).

We delivered a copy of this Current Report on Form 8-K to Ernst & Young LLP and requested that a letter addressed to the Securities and Exchange Commission stating whether or not it agrees with the statements made in response to this Item and, if not, stating the respects in which it does not agree. Ernst & Young LLP responded with a letter dated July 21, 2020, a copy of which is annexed hereto as Exhibit 16.1, stating that Ernst & Young LLP agrees with the statements set forth above.

(b) Also on July 17, 2020, the Audit Committee approved the engagement of Mayer Hoffman McCann P.C. (“Mayer Hoffman”) as the Company’s independent registered public accounting firm for the year ending December 31, 2020.

Prior to the completion of the Merger, Mayer Hoffman served as the independent auditors of Forte Subsidiary.

During the years ended December 31, 2019 and 2018, neither the Company, nor anyone on the Company’s behalf, consulted with Mayer Hoffman regarding either (i) the application of accounting principles to a specific transaction, completed or proposed, or the type of audit opinion that might be rendered on the Company’s financial statements, and neither a written report nor oral advice was provided to the Company that Mayer Hoffman concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing or financial reporting issue or (ii) any matter that was either the subject of a disagreement (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) or a reportable event (as described in Item 304(a)(1)(v) of Regulation S-K).