Company: IMRX
Filing Date: 2025-09-25
Form Type: 424B5
Source: 0001104659-25-093438
Chunk: 11

Company: Immuneering Corp
Filing Date: 2025-09-25
Form: 424B5
Chunk 11
---
 2025 Employment Inducement Award Plan as of June 30, 2025; and

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5,251,349 outstanding shares of Class A common stock, 1,077,764 shares of Class A common stock issuable upon exercise of outstanding pre-funded warrants with an exercise price of $0.001 per share, and 2,848,096 shares of Class A common stock issuable upon exercise of outstanding purchase warrants with an exercise price of $5.50 per share, in each case, issued on August 26, 2025 pursuant to the terms of that certain securities purchase agreement, dated as of August 21, 2025, by and among us and the purchasers party thereto.

Unless otherwise indicated, this prospectus supplement reflects and assumes the following:

•

no exercise of the outstanding options or warrants described above; and

•

no exercise by the underwriters of their option to purchase additional shares of our Class A common stock.

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TABLE OF CONTENTS

### RISK FACTORS
Investment in any securities offered pursuant to this prospectus supplement and the accompanying prospectus involves risks. You should carefully consider the risk factors described below and in our Annual Report on Form 10-K for the year ended December 31, 2024incorporated by reference in this prospectus supplement, any amendment or update thereto reflected in subsequent filings with the SEC, including in our Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q, and all other information contained or incorporated by reference in this prospectus supplement, as updated by our subsequent filings under the Exchange Act. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities. Please also refer to the section entitled “Cautionary Note Regarding Forward-Looking Statements” included elsewhere in this prospectus supplement.

#### Risks Related to this Offering
If you purchase securities sold in this offering, you will experience immediate and substantial dilution in the net tangible book value of your investment. In addition, we may issue additional equity or convertible debt securities in the future, which may result in additional dilution to you.

The price per share of our securities being offered may be higher than the net tangible book value per share of our outstanding common stock prior to this offering. The sale of 18,959,914 shares of Class A common stock in this offering and 2,708,559 shares of Class A common stock in the