Amendment Number One to Collaboration and License Agreement, dated August 3, 2023, by and between Arcturus Therapeutics, Inc. and Seqirus Inc

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Certain identified information, indicated by [***], has been excluded from the exhibit because it is both (i) not material and (ii) would likely cause competitive harm if publicly disclosed.

Amendment number one

to COLLABORATION AND LICENSE AGREEMENT

This Amendment Number One to Collaboration and License Agreement (this “Amendment”) is made and entered into on August 3, 2023 (the “Amendment Effective Date”) and amends the Collaboration Agreement by and between Arcturus Therapeutics, Inc., a Delaware corporation (“Arcturus”), and Seqirus Inc., a Delaware corporation (“Seqirus”). Arcturus and Seqirus are sometimes referred to herein individually as a “Party” and together as the “Parties.” Capitalized terms used in this Amendment that are not defined herein shall have the meanings ascribed to such terms in the Collaboration Agreement.

Recitals

WHEREAS, Arcturus and Seqirus are parties to that certain Collaboration and License Agreement (“Collaboration Agreement”) executed on November 1, 2022 and with an effective date of December 8, 2022 (the “Collaboration Agreement Effective Date”); and

WHEREAS, the Parties desire that Arcturus sponsor and have conducted a Phase 1 clinical study in the Influenza Field as further described herein, and the Parties desire to set forth payment obligations of Seqirus in connection therewith;

NOW, THEREFORE, in consideration of the premises and the mutual promises and conditions hereinafter set forth, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties, intending to be legally bound, do hereby agree as follows:

3.2.7. Influenza Field Phase 1 Study.

(i) Arcturus will use Commercially Reasonable Efforts to act as the sponsor of the Influenza Phase I Study and to undertake additional related activities assigned to Arcturus as outlined in the Influenza Phase I Development Plan (collectively, the “Influenza Phase I Study Activities”). Influenza Phase I Study Activities include [***], [***], [***], and [***] pre-clinical and [***] do not include (i) [***], (ii) [***], [***].

(ii) The Parties shall review and mutually agree on any updates to the [***] . The JDC shall review [***] covering [***] at least [***] for the purpose of considering appropriate amendments thereto. In addition, either Party, through its representatives on the JDC, may propose amendments to [***] for [***] at any time.

6.3.2(viii) Upon execution of the Start Up Agreement, Seventeen Million Five Hundred Thousand Dollars ($17,500,000) (“Payment One”);

6.3.2(ix) Upon [***], [***], or [***] (such amount, “Payment Two”); provided for clarity that, for purposes of such calculation, [***] may apply any [***] permitted to be applied for up to and [***], subject to [***];

6.3.2(x) Upon completion of [***], [***], or [***] (such amount, “Payment Three”); and

6.3.2(xi) Upon completion of [***], [***], or [***] (such amount, “Payment Four”). If clause (ii) exceeds clause (i), then such amount shall be [***].

“3.6.3 R&D Credit. [***] will provide [***] with [***] in credit (“[***]”) toward [***] conducted during the [***]. [***] will allocate the [***] as it deems necessary to fulfill the

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activities set forth in the [***] or the [***] (but, for the avoidance of doubt, not as a credit against any milestone payments except for the [***] set forth in [***]; provided, however, that [***] may [***] up to (i) [***] against [***] payable [***] and [***], (ii) [***] of [***] against [***] payable [***] and (iv[***] of [***] against [***] for [***]. If any [***] is [***] at [***] it will be [***] to [***], until [***] at which time [***].”

“Plan” means a [***] .

[SIGNATURE PAGE FOLLOWS.]

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THIS AMENDMENT IS EXECUTED by the authorized representatives of the Parties as of the Amendment Effective Date.

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Attachment 1.1 to the Amendment

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Attachment A to [***]

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Attachment B to [***]

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Attachment 1.6 to [***]

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