November 17, 2016


Board of Directors

Arch Therapeutics, Inc.

235 Walnut Street, Suite 6

Framingham, MA 01702


Re: Registration Statement/Form S-3




We have acted as special Nevada counsel to Arch Therapeutics, Inc. (the “Company”) in connection with the filing by the Company of that certain Registration Statement on Form S-3, (the “Registration Statement”), with the Securities and Exchange Commission in connection with the registration under the Securities Act of 1933, as amended (the “Securities Act”), of the offering from time to time by the selling securityholders, as described in the Registration Statement, of up to 2,500,000 shares of the Company’s Common Stock, par value $0.001 per share (the “Common Shares”), as more fully described in the Registration Statement. Pursuant to Rule 416 under the Securities Act, the securities registered under the Registration Statement include such indeterminate number of additional shares of Common Stock of the Company as may be issued or issuable because of stock splits, stock dividends, stock distributions, and similar transactions.


As the special Nevada counsel to the Company in connection with the Registration Statement, we have examined the actions taken by the Company in connection with the authorization of the issuance of the Common Shares, the Warrants, and the Warrant Shares, and such documents as we have deemed necessary to render this opinion.


Based upon and subject to the foregoing, it is our opinion that the Common Shares to be sold by the selling securityholders pursuant to the Registration Statement have been duly authorized and are validly issued, fully paid and non-assessable.


We consent to the use of this opinion as an exhibit to the Registration Statement and further consent to all references to us in the Registration Statement and any amendment thereto.


  /s/ McDonald Carano Wilson LLP