UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the Month of June 2021

Commission File Number: 001-39621

OPTHEA LIMITED

(Translation of registrant’s name into English)

Level 4

650 Chapel Street

South Yarra, Victoria 3141

Australia

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  ☒            Form 40-F  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

EXHIBITS

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Exhibit 99.1

Appendix 3X

Initial Director’s Interest Notice

Rule 3.19A.1

Appendix 3X

Initial Director’s Interest Notice

Information or documents not available now must be given to ASX as soon as available. Information and documents given to ASX become ASX’s property and may be made public.

Introduced 30/9/2001.

We (the entity) give ASX the following information under listing rule 3.19A.1 and as agent for the director for the purposes of section 205G of the Corporations Act.

Part 1 - Director’s relevant interests in securities of which the director is the registered holder

In the case of a trust, this includes interests in the trust made available by the responsible entity of the trust

Note: In the case of a company, interests which come within paragraph (i) of the definition of “notifiable interest of a director” should be disclosed in this part.

Appendix 3X

Initial Director’s Interest Notice

Part 2 – Director’s relevant interests in securities of which the director is not the registered holder

In the case of a trust, this includes interests in the trust made available by the responsible entity of the trust

Part 3 – Director’s interests in contracts

Note: In the case of a company, interests which come within paragraph (ii) of the definition of “notifiable interest of a director” should be disclosed in this part.

Exhibit 99.2

Appendix 3X

Initial Director’s Interest Notice

Rule 3.19A.1

Appendix 3X

Initial Director’s Interest Notice

Information or documents not available now must be given to ASX as soon as available. Information and documents given to ASX become ASX’s property and may be made public.

Introduced 30/9/2001.

We (the entity) give ASX the following information under listing rule 3.19A.1 and as agent for the director for the purposes of section 205G of the Corporations Act.

Part 1 - Director’s relevant interests in securities of which the director is the registered holder

In the case of a trust, this includes interests in the trust made available by the responsible entity of the trust

Note: In the case of a company, interests which come within paragraph (i) of the definition of “notifiable interest of a director” should be disclosed in this part.

Appendix 3X

Initial Director’s Interest Notice

Part 2 – Director’s relevant interests in securities of which the director is not the registered holder

In the case of a trust, this includes interests in the trust made available by the responsible entity of the trust

Part 3 – Director’s interests in contracts

Note: In the case of a company, interests which come within paragraph (ii) of the definition of “notifiable interest of a director” should be disclosed in this part.