Exhibit 5.1

	140 Scott Drive Menlo Park, California 94025 Tel: +1.650.328.4600 Fax: +1.650.463.2600 www.lw.com
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May 6, 2021	Düsseldorf	San Diego
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Arcutis Biotherapeutics, Inc. 2945 Townsgate Road, Suite 110 Westlake Village, California 91361	London	Singapore
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	Milan

Re:     Registration Statement on Form S-3 (No. 333-252612)

    Up to $100,000,000 shares of common stock, $0.0001 par value per share

Ladies and Gentlemen:

We have acted as special counsel to Arcutis Biotherapeutics, Inc., a Delaware corporation (the “Company”), in connection with the proposed issuance from time to time of shares of common stock of the Company, $0.0001 par value per share (the “Common Stock”), having an aggregate offering price of up to $100,000,000 (the “Shares”), by the Company pursuant to the Sales Agreement, dated May 6, 2021 (the “Sales Agreement”) between the Company and Cowen and Company, LLC. The Shares are included in a registration statement on Form S-3 under the Securities Act of 1933, as amended (the “Act”), filed with the Securities and Exchange Commission (the “Commission”) on February 1, 2021 (Registration No. 333-252612) (as amended, the “Registration Statement”) and are being offered pursuant to a base prospectus dated February 1, 2021 (the “Base Prospectus”) and a prospectus supplement dated May 6, 2021 filed with the Commission pursuant to Rule 424(b) under the Act (together with the Base Prospectus, the “Prospectus”).

This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement or the Prospectus, other than as expressly stated herein with respect to the issue of the Shares.

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May 6, 2021

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As such counsel, we have examined such matters of fact and questions of law as we have considered appropriate for purposes of this letter. With your consent, we have relied upon certificates and other assurances of officers of the Company and others as to factual matters without having independently verified such factual matters. We are opining herein as to the General Corporation Law of the State of Delaware (the “DGCL”), and we express no opinion with respect to any other laws.

Subject to the foregoing and the other matters set forth herein, it is our opinion that, as of the date hereof, when the Shares shall have been duly registered on the books of the transfer agent and registrar therefor in the name or on behalf of the purchasers, and have been issued by the Company against payment therefor (not less than par value) in the circumstances contemplated by the Sales Agreement, the issuance and sale of the Shares will have been duly authorized by all necessary corporate action of the Company, and the Shares will be validly issued, fully paid and nonassessable. In rendering the foregoing opinion, we have assumed that (i) the Company will comply with all applicable notice requirements regarding uncertificated shares provided in the DGCL and (ii) upon the issuance of any of the Shares, the total number of shares of Common Stock issued and outstanding will not exceed the total number of shares of Common Stock that the Company is then authorized to issue under its Certificate of Incorporation.

This opinion is for your benefit in connection with the Registration Statement and may be relied upon by you and by persons entitled to rely upon it pursuant to the applicable provisions of the Act. We consent to your filing this opinion as an exhibit to the Company’s Current Quarterly Report on Form 10-Q for the three month period ended March 31, 2021 and to the reference to our firm in the Prospectus under the heading “Legal Matters.” In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission thereunder.

Very truly yours,

/s/ Latham & Watkins LLP

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