UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G/A

Under the Securities Exchange Act of 1934

(Amendment No. 6)*

InSite Vision Incorporated

(Name of Issuer)

Common Stock, $0.01 par value per share

(Title of Class of Securities)

457660108

(CUSIP Number)

August 10, 2015

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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Item 1.

InSite Vision Incorporated

965 Atlantic Avenue, Alameda, CA 94501

Item 2.

This Schedule 13G is being filed on behalf of Coliseum Capital Management, LLC (“CCM”), Coliseum Capital, LLC (“CC”), Coliseum Capital Partners, L.P. (“CCP”), Adam Gray (“Gray”) and Christopher Shackelton (“Shackelton” and together with CCM, CC, CCP and Gray, the “Reporting Persons”).

The address of the principal business and office of the Reporting Persons is Metro Center, 1 Station Place, 7th Floor South, Stamford, CT 06902.

Common Stock, $0.01 par value per share (“Common Stock”)

457660108

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If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:            

The information relating to the beneficial ownership of Common Stock by each of the Reporting Persons set forth in Rows 5 through 9 and Row 11 of the cover pages hereto is incorporated herein by reference.

The ownership percentage of each Reporting Person set forth in Row 11 of the cover pages hereto has been calculated based on an assumed total of 131,951,033 shares of Common Stock outstanding as of July 9, 2015, as reported in the Issuer’s prospectus, dated July 16, 2015, as filed with the Securities and Exchange Commission pursuant to Rule 424(b)(3) on July 16, 2015.

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class securities, check the following x

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Not applicable.

Not applicable.

The Reporting Persons may be deemed to be members of a group with respect to the Common Stock owned of record by CCP and a separate account managed by CCM (the “Separate Account”). CCP is the direct owner of 1,508,060 shares of Common Stock and the Separate Account is the direct owner of 2,311,252 shares of Common Stock.

Not applicable.

By signing below, I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

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SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: August 12, 2015

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EXHIBITS

EXHIBIT 24

POWER OF ATTORNEY

July 29, 2015

Know all by these presents, that the undersigned hereby constitutes and appoints Christopher Shackelton the undersigned’s true and lawful attorney-in-fact to:

1. execute for and on behalf of the undersigned, in the undersigned’s capacity as a beneficial owner and possibly a director by deputization, as applicable, of InSite Vision Incorporated (the “Company”), (a) Schedules 13D and 13G (and any amendments thereto) in accordance with Sections 13(d) and 13(g) of the Securities Exchange Act of 1934 (the “Exchange Act”) and the rules thereunder, (b) Forms 3, 4, and 5 (and any amendments thereto) in accordance with Section 16(a) of the Exchange Act and the rules thereunder, and (c) any other forms or reports the undersigned may be required to file in connection with the undersigned’s ownership, acquisition, or disposition of securities of the Company;

2. do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete and execute any such Schedule 13D, Schedule 13G, Form 3, 4, or 5, or other form or report (or any amendment thereto), and timely file such schedule, form or report with the U.S. Securities and Exchange Commission and any stock exchange or similar authority; and

3. take any other action of any type whatsoever in connection with the foregoing which, in the opinion of such attorney-in-fact, may be of benefit to, in the best interest of, or legally required by, the undersigned, it being understood that the documents executed by such attorney-in-fact on behalf of the undersigned pursuant to this Power of Attorney shall be in such form and shall contain such terms and conditions as such attorney-in-fact may approve in such attorney-in-fact’s discretion.

The undersigned hereby grants to such attorney-in-fact full power and authority to do and perform any and every act and thing whatsoever requisite, necessary, or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that such attorney-in-fact, or such attorney-in-fact’s substitute or substitutes, shall lawfully do or cause to be done by virtue of this power of attorney and the rights and powers herein granted. The undersigned acknowledges that the foregoing attorney-in-fact, in serving in such capacity at the request of the undersigned, is not assuming, nor is the Company assuming, any of the undersigned’s responsibilities to comply with Section 13 and Section 16 of the Exchange Act.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file Schedules 13D and 13G and Forms 3, 4, and 5 with respect to the undersigned’s holdings of and transactions in securities issued by the Company, unless earlier revoked by the undersigned in a signed writing delivered to the foregoing attorney-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date first written above.