ARCT

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false 0001768224

0001768224

2026-03-03 2026-03-03

iso4217:USD

xbrli:shares

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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): March 3, 2026

ARCTURUS THERAPEUTICS

HOLDINGS INC.

(Exact name of registrant as specified in its charter)

Delaware

001-38942

32-0595345

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification No.)

10285 Science Center Drive, San Diego, California 92121

(Address of principal executive offices)

Registrant’s telephone number, including area code: (858) 900-2660

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:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class

Trading

Symbol(s)

Name of each exchange

on which registered

Common stock, par value $0.001 per share

ARCT

The Nasdaq Stock Market LLC

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. ☐

Item 2.02. Results of Operations and Financial Conditions.

On March 3, 2026, Arcturus Therapeutics Holdings Inc. (the “Company” or “Arcturus”) issued a press release, a copy of which is furnished herewith as Exhibit 99.1, announcing the Company’s financial results for the quarter and year ended December 31, 2025 and providing a corporate update (the “Press Release”).

The information contained in Item 2.02 of this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liability of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed incorporated by reference into any of the Company’s filings with the Securities and Exchange Commission (the “SEC”), except as shall be expressly set forth by specific reference in any such filing.

Cautionary Note Regarding Forward-Looking

Statements

This Current Report on Form 8-K and the Press Release contain forward-looking statements that involve substantial risks and uncertainties for purposes of the safe harbor provided by the Private Securities Litigation Reform Act of 1995. Any statements, other than statements of historical fact included in this Current Report on Form 8-K and the Press Release, are forward-looking statements, including those regarding strategy, future operations, the likelihood of success of the Company’s pipeline (including ARCT-032 and ARCT-810) and partnered programs (including the COVID-19 and flu programs partnered with CSL Seqirus), the likelihood that clinical data, including interim data, will be predictive of future clinical results, the likelihood of and timing for achieving alignment with regulators on the clinical strategy for ARCT-810, plans to broaden the development strategy for ARCT-810, the timing for Type C regulatory meetings for ARCT-810 and feedback therefrom, the likelihood of initiation, and size, scope, and timing, of a Phase 2, 12-week study for ARCT-032, the ongoing development of a self-amplifying mRNA pandemic influenza vaccine under its contract with BARDA, the likelihood that general and administrative expenses will continue to decrease slightly, its current cash position and expected cash burn and runway, and the impact of general business and economic conditions. Arcturus may not actually achieve the plans, carry out the intentions or meet the expectations or projections disclosed in any forward-looking statements such as the foregoing and you should not place undue reliance on such forward-looking statements. These statements are only current predictions or expectations, and are subject to known and unknown risks, uncertainties, and other factors that may cause our or our industry’s actual results, levels of activity, performance or achievements to be materially different from t

false 0001768224

0001768224

2025-11-10 2025-11-10

iso4217:USD

xbrli:shares

iso4217:USD

xbrli:shares

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): November 10, 2025

ARCTURUS THERAPEUTICS

HOLDINGS INC.

(Exact name of registrant as specified in its charter)

Delaware

001-38942

32-0595345

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification No.)

10285 Science Center Drive

San Diego, California 92121

(Address of principal executive offices)

Registrant’s telephone number, including area code: (858) 900-2660

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:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class

Trading

Symbol(s)

Name of each exchange

on which registered

Common stock, par value $0.001 per share

ARCT

The Nasdaq Stock Market LLC

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. ☐

Item 2.02. Results of Operations and Financial Conditions.

On November 10, 2025, Arcturus Therapeutics Holdings Inc. (the “Company” or “Arcturus”) issued a press release, a copy of which is furnished herewith as Exhibit 99.1, announcing the Company’s financial results for the quarter ended September 30, 2025 and providing a corporate update (the “Press Release”).

The information contained in Item 2.02 of this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liability of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed incorporated by reference into any of the Company’s filings with the Securities and Exchange Commission (the “SEC”), except as shall be expressly set forth by specific reference in any such filing.

Cautionary Note Regarding Forward-Looking

Statements

This Current Report on Form 8-K and the Press Release contains forward-looking statements that involve substantial risks and uncertainties for purposes of the safe harbor provided by the Private Securities Litigation Reform Act of 1995. Any statements, other than statements of historical fact included in this Current Report on Form 8-K and the Press Release, are forward-looking statements, including those regarding strategy, future operations, the likelihood of success of the Company’s pipeline (including ARCT-032 and ARCT-810) and partnered programs (including the COVID-19 and flu programs partnered with CSL Seqirus), the likelihood that clinical data, including interim data, will be predictive of future clinical results, the likelihood that observed mucus plug reduction is predictive of future and future reduction and will lead to lung function or structural lung defect improvements, the plans to enroll subjects in the third cohort of the Phase 2 clinical trial of ARCT-032, the likelihood and timing for initiation, and size and scope, of a planned 12-week safety and preliminary efficacy study for ARCT-032, plans to advance ARCT-032 further into development, the likelihood and timing for achieving alignment with regulatory agencies on pivotal studies for ARCT-810, the likelihood of success of any collaboration including the anticipated continued support from CSL to commercialize KOSTAIVE, the continued determination that ARCT-032 is generally safe and well tolerated, the likelihood of further development of a self-amplifying mRNA pandemic influenza vaccine candidate, the likelihood that preclinical or clinical data will be predictive of future clinical results, the likelihood that general and administrative expenses will continue to decrease, its current cash position and expected cash burn and runway, and the impact of general business and economic conditions. Arcturus may not actually ac