Company: INTS
Filing Date: 2025-12-04
Form Type: 424B5
Source: 0001567264-25-000108
Chunk: 1

Company: INTENSITY THERAPEUTICS, INC.
Filing Date: 2025-12-04
Form: 424B5
Chunk 1
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 29,026,358 shares of our common stock that are covered by the July 11, 2024 sales agreement prospectus pursuant to the Offering Agreement for an aggregate gross sales price of $10,227,589.

The purpose of this prospectus supplement is to update the July 11, 2024 sales agreement prospectus to reflect the ATM Offering Size Increase. Except as modified by this prospectus supplement, the terms of the ATM Offering remain unchanged, and the Offering Agreement remains in full force and effect.

The July 11, 2024 sales agreement prospectus and July 11, 2024 base prospectus and prior prospectus supplements dated November 20, 2024, June 11, 2025 and June 18, 2025, respectively, indicated that we were, at that time, subject to General Instruction I.B.6. of Form S-3, which limited the amount that we were able to sell under the registration statement of which the prospectus forms a part. We are currently no longer subject to the offering limits imposed by General Instruction I.B.6. of Form S-3. As of the date of this prospectus supplement, the aggregate market value of our outstanding shares of common stock held by non-affiliates, was approximately $76,499,742, which was calculated based on our 57,954,350 outstanding shares of common stock held by non-affiliates at a price of $1.32 per share, the closing price of our common stock on the Nasdaq Capital Market on October 30, 2025. If we become subject to the offering limits in General Instruction I.B.6. of Form S-3 in the future, we will file another prospectus supplement.

Our business and an investment in our common stock involve significant risks. These risks are described under the caption “Risk Factors” beginning on pages

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of the July 11, 2024 sales agreement prospectus and July 11, 2024 base prospectus, respectively, and in the documents incorporated by reference into the July 11, 2024 sales agreement prospectus and July 11, 2024 base prospectus, as well as the risks and uncertainties described in other documents we file with the Securities and Exchange Commission, or SEC.

Neither the SEC nor any state securities commission has approved of anyone’s investment in these securities or determined if this prospectus supplement, the July 11, 202