Material Agreement (Form 8-K)

Item 1.01. Entry into a Material Definitive Agreement.

On September 15, 2025, Shuttle Pharmaceuticals Holdings, Inc.(the "Company"), entered into a consulting agreement with IR Agency LLC (the "IR Agency"). Pursuant to the consulting agreement, IR Agency agreed to provide marketing and advertising services to communicate information about the Company to the financial community (the "Services"), including, but not limited to, creating company profiles, media distribution and building a digital community with respect to the Company. As consideration for the performance of the Services, the Company paid IR Agency $1,450,000. The term of the consulting agreement will be two months.

The foregoing description of the consulting agreement is qualified by reference to the full text of the consulting agreement, which is filed as Exhibit 10.1 hereto and incorporated herein by reference.