Candel Therapeutics Inc — Current Report (Form 8-K)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 15, 2026

CANDEL THERAPEUTICS, INC.

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: (617) 916-5445

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

On May 15, 2026, Candel Therapeutics, Inc. (the “Company”) held an investor presentation via live webcast to review extended follow-up data from the phase 3 clinical trial of aglatimagene besadenovec in localized prostate cancer, which was also presented by the Company during the American Urological Association 2026 Annual Meeting on May 15, 2026.

A copy of the investor presentation is furnished as Exhibit 99.1 to this Current Report on Form 8-K and incorporated by reference herein. The presentation will also be available on the investor relations section of the Company’s website at https://ir.candeltx.com/. Information contained on the Company’s website is not incorporated by reference into this Current Report on Form 8-K, and you should not consider any information on, or that can be accessed from, the Company’s website as part of this Current Report on Form 8-K.

Also, on May 15, 2026, the Company issued a press release announcing the presentation at the American Urological Association 2026 Annual Meeting. A copy of the full press release is furnished as Exhibit 99.2 to this Current Report on Form 8-K and incorporated by reference herein.

The information in this Item 7.01 and Exhibits 99.1 and 99.2 of this Current Report on Form 8-K are furnished and shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section. The information in this Item 7.01 and Exhibits 99.1 and 99.2 of this Current Report on Form 8-K shall not be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date of this Current Report on Form 8-K, regardless of any general incorporation language in any such filing.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.