ARCT

EX-99.1

2 e665679_ex99-1.htm

Arcturus Therapeutics Announces Second Quarter 2026 Financial Results and Pipeline Progress

ARCT-032 (CF) Phase

2 study enrollment remains on schedule; the decision to proceed into Phase 3 expected Q4 2026

ARCT-810 (OTC Deficiency)

Phase 2 study enrollment and dosing completed; data and regulatory plan to be communicated Q3 2026

Arcturus regains global rights to KOSTAIVE® and infectious disease portfolio; receives $12 million in cash and $16 million in released liabilities and R&D credits

Investor conference call at 4:30 p.m. ET today

SAN DIEGO--(BUSINESS WIRE) -- August 6, 2026 --

Arcturus Therapeutics Holdings Inc. (the “Company”, “Arcturus”, Nasdaq: ARCT), a messenger RNA medicines company focused on the development of liver and respiratory rare disease therapeutics, today announced its financial results for the quarter ended June 30, 2026, and provided corporate updates.

“We are encouraged by the continued progress of our ARCT-032 Phase 2 cystic fibrosis study, with active screening and ongoing enrollment across sites in the United States, Israel, and Turkey. With dosing completed of all subjects in our ARCT-810 Phase 2 OTC deficiency study, we look forward to sharing the data and regulatory plan later this quarter,” said Joseph Payne, President & CEO of Arcturus. "We are also pleased to regain strategic control of KOSTAIVE® and our infectious disease vaccine portfolio, enhancing our ability to increase the value of our validated sa-mRNA vaccine platform."

Recent Corporate Highlights

·ARCT-032, an inhaled mRNA therapeutic candidate for cystic fibrosis, continues to advance in an open-label Phase 2 study in people with Class I CF mutations. Cohort 4 is evaluating 10 mg daily dosing, via inhalation, over 12 weeks and monitoring safety and evidence of early clinical benefit, including pulmonary function measures such as ppFEV1 and lung clearance index (LCI), quality-of-life measures, and high-resolution computed tomography (HRCT) imaging. Enrollment is advancing as expected, with active screening and enrollment in the U.S., Israel, and Turkey. Israel and Turkey are geographies with a high prevalence of individuals with Class I/null CF mutations, supporting recruitment efforts in the ongoing study. The decision to advance ARCT-032 into Phase 3 is expected in Q4 2026, triggering significant resources and support from Thermo Fisher.

·Arcturus announced a strategic collaboration with Thermo Fisher Scientific to advance ARCT-032 for cystic fibrosis. Thermo Fisher will provide Phase 3 manufacturing, clinical research, and related services. If Phase 2 yields positive results, Arcturus expects to conduct its Phase 3 program through Thermo Fisher’s PPD™ clinical research business. Subject to regulatory approval of ARCT-032, Thermo Fisher will receive exclusive commercial manufacturing rights under a separate commercial agreement.

·ARCT-810, an mRNA therapeutic candidate for OTC deficiency, has completed enrollment of the ongoing Phase 2 study, and all enrolled subjects have completed study drug dosing. The Company continues to evaluate supplementary data to inform regulatory discussions and preparation for an End-of-Phase 2 meeting regarding the path forward across adult and pediatric development. Data and the regulatory plan for this program is expected to be communicated later this quarter.

·Arcturus and CSL Seqirus have concluded their sa-mRNA collaboration through a termination and settlement agreement following a joint review of the partnership. Under the agreement, Arcturus regained global rights to KOSTAIVE® and the broader infectious disease vaccine portfolio, including seasonal influenza, pandemic influenza, RSV, and EBV vaccine programs, subject to existing arrangements with Meiji Seika Pharma for the 2026-2027 season in Japan. The agreement also resolves the arbitration relating to a European regulatory approval milestone payment.

oUnder the agreement, CSL Seqirus will make a one-time cash payment of $12 million to Arcturus. In addition, Arcturus will be released from liabilities associated with an R&D credit with an aggregate value of approximately $16 million.

oWith strategic control of the portfolio returned to Arcturus, the Company intends to evaluate opportunities to maximize its future value, including development, commercialization, and partnering opportunities related to KOSTAIVE®, and the broader infectious disease vaccine portfolio.

“We remain focused on disciplined execution and capital allocation as we advance our rare disease programs,” said Dennis Mulroy, Chief Financial Officer of Arcturus. “The CSL Seqirus termination and settlement agreement strengthens our financial position, and the Thermo Fisher collaboration supports execution of late-stage development for our CF program. We continue to maintain a strong balance sheet and cash runway of over two and a half years through year end 2028, allowing our company to reach important clinical and reg

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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