Company: SION
Filing Date: 2025-04-29
Form Type: DEF 14A
Source: 0001193125-25-101830
Chunk: 27

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-04-29
Form: DEF 14A
Chunk 27
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. and Peter A. Thompson, M.D. serve on the nominating and corporate governance committee, which is chaired by Mr. Clancy. Our board of directors has determined that each member of the nominating and corporate governance committee is “independent” as defined in the applicable Nasdaq rules. During the fiscal year ended December 31, 2024, the nominating and corporate governance committee did not meet as it was first established in December 2024. The nominating and corporate governance committee’s responsibilities include:

| • |     | identifying and evaluating candidates, including the nomination of incumbent directors for reelection and nominees recommended by stockholders, to serve on our board of directors; |

| • |     | considering and making recommendations to our board of directors regarding the composition and chairmanship of the committees of our board of directors; |

| • |     | instituting plans or programs for the continuing education of our board of directors and orientation of new directors; |

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| • |     | developing and making recommendations to our board of directors regarding corporate governance guidelines and matters; and |

| • |     | overseeing periodic evaluations of the board of directors’ performance, including committees of the board of directors and management. |

Our nominating and corporate governance committee operates under a written charter that satisfies the applicable Nasdaq listing rules and is available at https://investors.sionnatx.com/corporate-governance/documents-charters. In identifying potential board of director candidates, the nominating and corporate governance committee considers individuals recommended by its own committee members, other members of the board of directors, and our chief executive officer. Additionally, the nominating and corporate governance committee will review candidates recommended by stockholders in the same manner and using the same general criteria as candidates recruited by the committee and/or recommended by our board of directors. Any stockholder who wishes to recommend a candidate for consideration by the committee as a nominee for director should follow the procedures described later in this proxy statement under the heading “ Stockholder Proposals.” The nominating and corporate governance committee will also consider whether to nominate any person proposed by a stockholder in accordance with the provisions of our bylaws relating to stockholder nominations as described later in this proxy statement under the heading “ Stockholder Proposals.” Board and Committee Meetings Attendance The full board of directors met seven times during 2024. During 2024, each member of the board of directors attended in person or participated in 75% or more of the aggregate of (i) the total number of meetings of the