OPT Opthea Ltd

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 August 2023

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 99.2

ASX, Nasdaq and Media Release

24 August 2023

Opthea announces Placement and fully underwritten Entitlement Offer to raise A$80.0 million (US$51.2 million¹)

Melbourne, Australia; 24 August 2023 – Opthea Limited (Opthea or the Company) (ASX:OPT; NASDAQ:OPT), (Opthea, OPT or the Company) a clinical stage biopharmaceutical company developing novel therapies to treat highly prevalent and progressive retinal diseases, today announced that the Company is seeking to raise A$80.0 million (US$51.2 million¹) via a A$10.0 million (US$6.4 million¹) private placement (“Placement”) and a $70.0 million (US$44.8 million¹) Accelerated Non-Renounceable Entitlement Offer (“ANREO” or “Entitlement Offer”).

The proceeds from the Placement and Entitlement Offer will be used to continue advancing the clinical development of OPT-302 for the treatment of wet Age-related Macular Degeneration (wet AMD), including to progress the Company’s Phase 3 clinical trials and for general corporate purposes.

Dr Megan Baldwin, Chief Executive Officer and Managing Director of Opthea commented “This institutional placement and entitlement offer strengthens Opthea’s cash position as we advance OPT-302 through Phase 3 clinical trials, ShORe and COAST. With the completion of this financing, together with the funding under the Development Funding Agreement (DFA) with Carlyle and Abingworth, which includes a further US$35.0 million of committed funding and the addition of a new co-investor of Carlyle and Abingworth which intends to participate in a funding under the DFA of US$50.0 million to increase total DFA funding from $120 million to $170 million which is subject to the co-investor’s final due diligence and approvals, appropriate documentation and compliance with closing conditions², the Company expects to fund its operations into the third quarter of calendar year 2024 and through the important clinical milestones of completion of patient recruitment for both Phase 3 clinical trials.”

With the announcement of the financing, Opthea provided an update on the progress of the Company’s Phase 3 program. The Phase 3 clinical trials are approximately 75% enrolled, with COAST expected to be fully enrolled in the first quarter calendar 2024 and ShORe in the second quarter of calendar 2024. Topline data is expected when all patients complete the 52-week treatment period.

Opthea is pleased to announce the launch of a capital raising comprising:

(collectively, the Offer or Capital Raising)

The offer price for the Placement and Entitlement Offer will be A$0.46 per New Share (Offer Price), representing a discount of:

Each New Share issued under the Capital Raising will rank equally with existing fully paid ordinary shares in OPT from the date of issue.

MST Financial Services Pty Ltd (MST) will act as sole lead manager to the Offer and sole underwriter to the Entitlement Offer.

Placement

The Placement is expected to raise up to approximately A$10.0 million (US$6.4 million¹) and is being undertaken utilizing the Company’s existing placement capacity under ASX Listing Rule 7.1. The Placement is not underwritten.

The Company in its sole discretion reserves the right to raise additional funds under the Placement. Any New Shares and New Options issued as a result of raising such additional funds will be issued within Opthea’s available placement capacity under ASX Listing Rule 7.1

Entitlement Offer

The fully underwritten Entitlement Offer of A$70.0 million (US$44.8 million¹) will consist of a 1 for 3.07 pro-rata accelerated non-renounceable entitlement offer.

The retail component of the Entitlement Offer (Retail Entitlement Offer) is open to eligible shareholders as at 7:00pm (Melbourne time) on Monday, 28 August 2023 (Record Date).

All New Shares issued under the Entitlement Offer will be issued at the Offer Price.

The Entitlement Offer is non-renounceable and accordingly entitlements will not be tradeable on the ASX or be otherwise transferable. Shareholders who do not take up their full entitlement will not receive any payment in respect of the entitlements they do not take up and their percentage equity interest in Opthea will be diluted.

OPT shares will remain in a trading halt pending completion and announcement of the Placement and the institutional component of the Entitlement Offer (Institutional Entitlement Offer).

For the avoidance of doubt, holders of the Company’s American Depositary Shares (Nasdaq:OPT) are not eligible to participate in the Entitlement Offer or receive New Options.

Institutional Entitlement Offer

Eligible institutional and sophisticated shareholders (Institutional Shareholders) will be invited to participate in the Institutional Entitlement Offer which will commence on Thursday, 24 August 2023.

Institutional Shareholders may opt to take up all, part or none of their entitlements. Entitlements not taken up by Institutional Shareholders together with those entitlements of ineligible institutional and retail shareholders, will be offered to other institutional and sophisticated investors at the Offer Price (Institutional Shortfall Offer).

Retail Entitlement Offer

Retail shareholders who have a registered address in Australia or New Zealand on the register as at 7:00pm (Melbourne time) on the Record Date will be invited to participate in the Retail Entitlement Offer at the same Offer Price and offer ratio as under the Institutional Entitlement Offer.

The Retail Entitlement Offer is expected to open on Thursday, 31 August 2023 and close at 5:00pm (Melbourne time) on Thursday, 14 September 2023.

The Retail Entitlement Offer will be made under a transaction specific prospectus issued under section 713 of the Corporations Act 2001 (Cth) (Prospectus). The Prospectus will be lodged with ASIC and the ASX on Thursday, 24 August 2023 and will be dispatched to eligible retail shareholders, along with personalized acceptance forms, on Thursday, 31 August 2023. The Prospectus will provide details of how to participate in the Retail Entitlement Offer. Eligible retail shareholders may opt to take up all, part or none of their entitlement. Eligible retail shareholders will also have the opportunity to apply for and be allocated additional New Shares up to 25% of their entitlement (subject to scale back at the sole discretion of Opthea) (Top-Up Facility).

Opthea may (in its absolute discretion) extend the Retail Entitlement Offer to any Institutional Shareholder that was eligible to, but was not invited to participate in, the Institutional Entitlement Offer (subject to compliance with relevant laws).

New Options

Participants in the Placement and Entitlement Offer will also be offered 1 option, each exercisable at A$0.80 per option and expiring on 31 August 2025 (New Options), for every 2 New Shares issued under the Placement and Entitlement Offer. The offer of New Options is made under the Prospectus.

All New Options are expected to be issued upon allotment of the Retail Entitlement Offer and, subject to satisfying spread requirements set out in ASX Listing Rule 2.5, condition 6, the Options are intended to be quoted on the ASX.

The full terms and conditions of the New Options will be set out in the Prospectus. Copies of the Prospectus will be available on the ASX website and at ww.opthea.com

The timetable below is indicative only and subject to change. The Company reserves the right to alter the dates below in its full discretion and without prior notice, subject to the ASX Listing Rules and the Corporations Act.

About Opthea Limited

Opthea (ASX:OPT; Nasdaq:OPT) is a biopharmaceutical company developing novel therapies to address the unmet need in the treatment of highly prevalent and progressive retinal diseases, including wet age-related macular degeneration (wet AMD) and diabetic macular edema (DME). Opthea’s lead product candidate OPT-302 is in pivotal Phase 3 clinical trials and being developed for use in combination with anti-VEGF-A monotherapies to achieve broader inhibition of the VEGF family, with the goal of improving overall efficacy and demonstrating superior vision gains over that which can be achieved by inhibiting VEGF-A alone.

Inherent risks of Investment in Biotechnology Companies

There are a number of inherent risks associated with the development of pharmaceutical products to a marketable stage. The lengthy clinical trial process is designed to assess the safety and efficacy of a drug prior to commercialization and a significant proportion of drugs fail one or both of these criteria. Other risks include uncertainty of patent protection and proprietary rights, whether patent applications and issued patents will offer adequate protection to enable product development, the obtaining of necessary drug regulatory authority approvals and difficulties caused by the rapid advancements in technology. Companies such as Opthea are dependent on the success of their research and development projects and on the ability to attract funding to support these activities. Investment in research and development projects cannot be assessed on the same fundamentals as trading and manufacturing enterprises. Therefore, investment in companies specializing in drug development must be regarded as highly speculative. Opthea strongly recommends that professional investment advice be sought prior to such investments.

Forward-looking statements

This ASX announcement contains certain forward-looking statements, including within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. The words “expect”, “anticipate”, “estimate”, “intend”, “believe”, “guidance”, “should”, “could”, “may”, “will”, “predict”, “plan” and other similar expressions are intended to identify forward-looking statements. Indications of, and guidance on, future financial position and performance including the preliminary estimated unaudited financial information and pro forma data, are also forward-looking statements. Forward-looking statements in this ASX announcement include statements regarding the timetable, conduct and outcome of the Offer and the use of the proceeds thereof, the therapeutic and commercial potential and size of estimated market opportunity of the Company’s product in development, the viability of future opportunities, future market supply and demand, the expected receipt of payments (including the additional potential increase of US$50 million of funding under the Development Funding Agreement (“DFA”)) and the timing of such payments, Opthea’s expected cash runway, the expected timing of completion of patient enrollment under the clinical trials and timing of top-line

data, expectations about topline data and other observations and expectations based on masked pooled data, the financial condition, results of operations and businesses of Opthea, certain plans, objectives and strategies of the management of Opthea, including with respect to the current and planned clinical trials of its product candidate, and the future performance of Opthea. Forward-looking statements, opinions and estimates provided in this ASX announcement are based on assumptions and contingencies which are subject to change without notice, as are statements about market and industry trends, which are based on interpretations of current conditions.

Forward-looking statements, including projections, guidance on the future financial position of the Company including the preliminary estimated unaudited financial information and pro forma data, are provided as a general guide only and should not be relied upon as an indication or guarantee of future performance. They involve known and unknown risks and uncertainties and other factors, many of which are beyond the control of Opthea and its directors and management and may involve significant elements of subjective judgment and assumptions as to future events that may or may not be correct. These statements may be affected by a range of variables which could cause actual results or trends to differ materially, including but not limited to the availability of funding, the receipt of funding under the DFA (including the additional potential increase of US$50 million of funding under the DFA), future capital requirements, the development, testing, production, marketing and sale of drug treatments, regulatory risk and potential loss of regulatory approvals, ongoing clinical studies to demonstrate OPT-302 safety, tolerability and therapeutic efficacy, additional analysis of data from Opthea’s Phase 3 clinical trials once unmasked, timing of completion of Phase 3 clinical trial patient enrollment and CRO and labor costs, intellectual property protections, the successful completion of the Offer, completion of management’s and the Company’s audit and risk committee’s review and the Company’s other closing processes, and other factors that are of a general nature which may affect the future operating and financial performance of the Company. Actual results, performance or achievement may vary materially from any projections and forward-looking statements and the assumptions on which those statements are based. Subject to any continuing obligations under applicable law or any relevant ASX listing rules, Opthea disclaims any obligation or undertaking to provide any updates or revisions to any forward-looking statements in this ASX announcement to reflect any change in expectations in relation to any forward-looking statements or any change in events, conditions or circumstances on which any such statement is based.

Not an offer

This ASX announcement is not a disclosure document and should not be considered as investment advice. The information contained in this ASX announcement is for information purposes only and should not be considered an offer or an invitation to acquire Company securities or any other financial products and does not and will not form part of any contract for the acquisition of New Shares.

In particular, this ASX announcement does not constitute an offer to sell, or a solicitation of any offer to buy, any securities in the United States or any other jurisdiction in which such an offer would be illegal or impermissible. The securities to be offered and sold in the Placement and SPP have not been, and will not be, registered under the U.S. Securities Act of 1933, as amended (the “U.S. Securities Act”), or the securities laws of any state or other jurisdiction of the United States. No public offering of securities is being made in the United States. Accordingly, the securities to be offered and sold in the Placement and SPP may only be offered and sold outside the United States in “offshore transactions” (as defined in Rule 902(h) under Regulation S of the U.S. Securities Act (“Regulation S”)) in reliance on Regulation S, unless they are offered and sold in a transaction registered under, or exempt from, or in a transaction not subject to, the registration requirements of, the U.S. Securities Act and applicable U.S. state securities laws.

Authorized for release to ASX by Megan Baldwin, CEO & Managing Director

Media:

Hershel Berry

Blueprint Life Science Group

Tel: +1 415 505 3749

hberry@bplifescience.com

Join our email database to receive program updates:

Tel: +61 (0) 3 9826 0399    Email: info@opthea.com    Web: www.opthea.com

Exhibit 99.3

Opthea Limited

ACN 006 340 567

Prospectus

For the offer of:

TABLE OF CONTENTS

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Chairman’s Letter

Thursday, 24 August 2023

Dear Shareholder

As announced by the Company to ASX today, Thursday, 24 August 2023, the Company intends to raise up to approximately $80.0 million by way of:

to raise approximately $70.0 million.

For every 2 New Shares subscribed for by participants under the Placement and Institutional Entitlement Offer, each participant will also receive, for no additional consideration, 1 Option to acquire 1 Share by way of issue which will be exercisable at $0.80 per Share. The Company will apply to have the Options quoted on the ASX and the Options will expire at 5.00pm (Melbourne time) on 31 August 2025.

As an Eligible Shareholder, you can choose to take up all, part or none of your Entitlement. If you choose to take up your full Entitlement, you may also apply for additional New Shares in excess of your Entitlement under a Top-Up Facility. The maximum number of additional New Shares that an Eligible Shareholder may apply for is 25.0% of their Entitlement.

The retail component of the Entitlement Offer will give all Eligible Shareholders an opportunity to apply for 1 New Share for every 3.07 Existing Shares at the Offer Price of $0.46 per New Share, being the same offer price per New Share under the Placement and Institutional Entitlement Offer, while also receiving, for no additional consideration, 1 option for every 2 New Shares to raise approximately $70.0 million. The New Options issued under the Retail Entitlement Offer will have the same terms as the Institutional Options to be issued to participants in the Placement and the Institutional Entitlement Offer.

Funds raised through the Capital Raising, are intended to be used by Opthea to continue advancing the clinical development of OPT-302 for the treatment of wet AMD, including to progress the Phase 3 clinical program and for general corporate purposes, as well as the other purposes described in this Prospectus.

Additionally, funds received by the Company from the exercise of the Options, which are exercisable at any time prior to the Expiry Date, will be primarily used to provide further funding for the same purposes as listed above.

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The Retail Entitlement Offer is open to all Shareholders recorded as holding Shares on the Company’s register of members as at 7.00pm (Melbourne, Australia time) on Monday, 28 August 2023 and who have a registered address in Australia or New Zealand (and who otherwise meet the eligibility criteria set out in Section 2.4).

The issue of New Shares under the Entitlement Offer is fully underwritten by the Underwriter, MST Financial Services Pty Ltd. The Placement is not underwritten.

Participation in the Retail Entitlement Offer is completely optional, however, a Shareholder’s entitlement to participate in the Retail Entitlement Offer is non-renounceable meaning that a Shareholder’s right to participate in the Retail Entitlement Offer cannot be transferred to anyone else. If you do not take up your Entitlement, you will not be allocated New Shares and your Entitlements will lapse. If you do not take up your Entitlement, your proportionate equity interest in Opthea will be diluted as a result of the Entitlement Offer.

If you are eligible and wish to participate in the Retail Entitlement Offer, you should submit a BPAY^® payment in accordance with the instructions on the accompanying personalised Application Form. New Zealand holders will not be able to make a payment using BPAY^® and should contact the Share Registry to obtain payment details. Your application and payment must be received by no later than 5.00pm (Melbourne time) on Thursday, 14 September 2023.

You should be aware that your own financial institution may implement earlier cut-off times with regard to electronic payment, and you should therefore take this into consideration when making payment. It is your responsibility to ensure that Application Monies submitted through BPAY^® are received by 5.00pm (Melbourne time) on Thursday, 14 September 2023.

The Board recommends that you read this Prospectus carefully, and in its entirety, before you decide whether to participate in the Offers. In particular, you should note the future market price of the Shares is uncertain and may rise or fall. This means the price you pay for New Shares under the Retail Entitlement Offer may be either higher or lower than the Share price as traded on ASX at the time the New Shares are issued to you under the Retail Entitlement Offer, with the effect that the value of your investment in the Securities could rise or fall. In deciding whether to participate in the Offers, you should seek your own independent financial, legal and taxation advice in respect of the Offers. No cooling off regime applies to the acquisition of Securities under the Offers.

On behalf of the Directors, I invite you to consider participating in the Offers and thank you for your ongoing support of Opthea.

Yours sincerely,

Dr. Jeremy Levin

Board Chairman

Opthea Limited

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Key Dates

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The below information is a selective overview of the Retail Entitlement Offer and Institutional Option Offer only. Participants should read the Prospectus in full before deciding to invest in Securities.

Retail Entitlement Offer

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Institutional Option Offer

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Under this Prospectus, the Company invites each Eligible Shareholder to subscribe for 1 New Share for every 3.07 Existing Shares held on the Record Date and 1 New Option for every 2 New Shares issued, free of brokerage or other transaction costs. The Retail Entitlement Offer is non-renounceable. This means that Eligible Shareholders who do not take up their Entitlements by 5.00pm (Melbourne time) on Thursday, 14 September 2023, will not receive any payment or value for those Entitlements, and their proportionate equity interest in the Company will be diluted.

Eligible Shareholders who take up their full Entitlement may also apply for additional New Shares under the Top-Up Facility. The maximum number of additional New Shares that an Eligible Shareholder may apply for is 25.0% of their Entitlement. Further details on how to take up your Entitlement and additional New Shares under the Top-Up Facility are contained in Section 2.5 and the personalized Entitlement and Acceptance Form.

Under the Retail Entitlement Offer, the Company is seeking to raise approximately A$16.5 million through the issuance of approximately 35.9 million New Shares and approximately 18.0 million New Options to Eligible Shareholders.

Any fractional entitlements will be rounded to the nearest whole number of New Shares or New Options (as applicable).

All New Shares offered under this Prospectus will rank equally with the Existing Shares on issue as at their date of issue. The material rights and liabilities attaching to the New Shares and New Options are set out in Section 6.5 and Section 6.6 respectively.

The purpose of the Entitlement Offer and the intended use of funds raised are set out in Section 4.

Eligible Shareholders are being offered the opportunity to acquire New Shares at the same price as investors under the Placement and the Institutional Entitlement Offer.

The Offer Price represents a discount of:

The Retail Entitlement Offer opens on 9.00am (Melbourne time) on Thursday, 31 August 2023 and is scheduled to close at 5.00pm (Melbourne time) on Thursday, 14 September 2023.

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The Company reserves the right to:

at any time. The Company will announce to ASX any such extension, early closure or withdrawal. Eligible Shareholders who wish to apply for New Shares and New Options under the Retail Entitlement Offer are encouraged to make their Application as soon as possible.

Participation in the Retail Entitlement Offer is optional, subject to the eligibility criteria set out below and the terms and conditions of this Prospectus.

The Retail Entitlement Offer is only open to Eligible Shareholders. An eligible shareholder is a person who:

(Eligible Shareholder).

Shareholders who are not Eligible Shareholders are ‘Ineligible Shareholders’. The Company reserves the right to determine whether a Shareholder is an Eligible Shareholder or an Ineligible Shareholder.

Joint holders of Shares will be taken to be a single registered holder of Shares for the purposes of determining whether they are an Eligible Shareholder.

The Company has determined that it is either unlawful or impracticable for holders of Shares with registered addresses in jurisdictions outside Australia (and its external territories) or New Zealand to participate in the Retail Entitlement Offer.

The Company reserves the right to reject any Application for New Shares and New Options under this Prospectus to the extent it considers that the Application (whether alone or in conjunction with other Applications) does not comply with these requirements.

If you are in any doubt about the Retail Entitlement Offer, whether you should participate in the Retail Entitlement Offer or how such participation will affect you, you should seek independent financial and taxation advice before making a decision as to whether or not to take up any New Shares and New Options under the Retail Entitlement Offer.

Eligible Shareholders who take up their Entitlement in full may apply for additional New Shares at the

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same Offer Price of $0.46 per New Share under the Top-Up Facility. The maximum number of additional New Shares that an Eligible Shareholder may apply for is 25.0% of their Entitlement. Allocations of New Shares under the Top-Up Facility are at the discretion of Opthea (as is the right to issue any shortfall under the Retail Entitlement Offer). Such New Shares are to be drawn from the Entitlements (or the parts thereof) that are not taken up by Eligible Shareholders. Accordingly, allocations available to be made under the Top-Up Facility will depend upon the extent to which Eligible Shareholders take up their Entitlements under the Retail Entitlement Offer. If the number of additional New Shares for which applications are received under the Top-Up Facility exceeds the number of New Shares available for allocation under the Top-Up Facility, then Opthea may apply any scaleback in its discretion, which may include having regard to the pro rata Entitlement of Eligible Shareholders who apply for additional New Shares. New Shares allocated under the Top-Up Facility will be issued at the same time as other New Shares under the Retail Entitlement Offer. For the avoidance of doubt, Eligible Shareholders who are issued additional New Shares will also receive, for no additional consideration, 1 option for every 2 additional New Shares.

The issue of New Shares under the Retail Entitlement Offer is fully underwritten by the Underwriter, MST Financial Services Pty Ltd, subject to the terms and conditions of the Underwriting Agreement. Please refer to Section 2.12 for further details in relation to the Underwriting Agreement.

It is important to note that the Underwriter will be acting for, and providing services to, the Company in relation to the Retail Entitlement Offer and will not be acting for or providing services to Shareholders. The Underwriter has been engaged solely as an independent contractor and is acting solely in a contractual relationship on an arm’s length basis with the Company. The engagement of the Underwriter by the Company is not intended to create any agency or other relationship between the Underwriter and Shareholders.

Under the Retail Entitlement Offer, Eligible Shareholders may subscribe for 1 New Share for every 3.07 Existing Shares held on the Record Date and 1 New Option for every 2 New Shares issued.

If you are an Eligible Shareholder you may:

If you are an Eligible Shareholder and wish to take up all or part of your Entitlement, or you wish to also apply for additional New Shares, you should:

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Any fractional entitlements will be rounded to the nearest whole number of New Shares or New Options (as applicable).

Any amounts received in excess of the Offer Price multiplied by your Entitlement may be treated as an Application to apply for as many additional New Shares as your Application Monies will pay for in full. Any Application Monies received for more than an Applicant’s final allocation of New Shares (and only where the amount is $5.00 or greater) will be refunded, without interest.

You cannot withdraw or revoke your Application once you have paid via BPAY^®.

If an Eligible Shareholder holds Shares as a custodian or nominee the Retail Entitlement Offer is also being made to the custodian or nominee and, subject to certain conditions, the custodian or nominee has the discretion to extend the Offer to the relevant beneficiaries. Please refer to Section 2.13 for further details.

For payment by BPAY^®, please follow the instructions on the accompanying personalised Application Form. You can only make a payment via BPAY^® if you are the holder of an account with an Australian financial institution that supports BPAY^® transactions. Please note that if you pay by BPAY^® you do not need to submit the accompanying personalised Application Form but are taken to have made the declarations in that Application Form.

New Zealand holders will not be able to make a payment using BPAY^® and should contact the Share Registry to obtain payment details.

Any amounts received in excess of the Offer Price multiplied by your Entitlement may be treated as an Application to apply for as many additional New Shares as your Application Monies will pay for in full.

It is your responsibility to ensure that your BPAY^® payment is received by the Share Registry by no later than 5.00pm (Melbourne time) on the Closing Date. You should be aware that your financial institution may implement earlier cut-off times with regards to electronic payment and you should therefore take this into consideration when making payment. No interest will be paid on any application monies received or refunded.

If you decide not to take up all or part of your Entitlement, the Entitlement which is unexercised will lapse and may be taken up by the Underwriter (or by persons they nominate, including any potential sub-underwriters). Your Entitlement to participate in the Retail Entitlement Offer is non- renounceable and cannot be traded on the ASX nor any other financial markets, nor can it be privately transferred.

If you decide not to participate in the Retail Entitlement Offer, you do not need to fill out or return the accompanying personalised Application Form. By allowing your Entitlement to lapse, you will forgo any exposure to increases or decreases in the value of the New Shares or New Options had you taken up your Entitlement and you will not receive any value for your Entitlement. Your proportionate interest in Opthea will also be diluted by the extent that New Shares are issued under the Retail Entitlement Offer.

If you are an Ineligible Shareholder, you may not take up any of, or do anything in relation to, your Entitlement under the Retail Entitlement Offer.

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If you apply for New Shares and New Options under the Retail Entitlement Offer or make a payment by BPAY^®, you:

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The Company has entered into an underwriting agreement with the Underwriter (Underwriting Agreement). Under the Underwriting Agreement, the Underwriter was appointed by the Company on an exclusive basis, to act as lead manager for the Capital Raising and as underwriter for the issue of New Shares under the Placement and the Entitlement Offer. The obligations of the Underwriter are subject to the satisfaction of certain conditions precedent, including (but not limited to):

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The Company has (subject to certain limitations) agreed to indemnify the Underwriter and its related bodies corporate and each of any of their respective directors, officers, employees, agents, advisers and representatives against certain losses in connection with the Capital Raising or the performance of the Underwriter’s obligations under the Underwriting Agreement.

The Company and the Underwriter have given certain representations, warranties and undertakings in connection with (among other things) the conduct of the Entitlement Offer.

The Underwriter will be remunerated by the Company for providing these underwriting services at market rates and be reimbursed for certain expenses. The Underwriter has not authorised or caused the issue of, and takes no responsibility for, this Prospectus, and to the maximum extent permitted by law, disclaims all liability in connection with the Entitlement Offer and this Prospectus.

The Underwriter may (in certain circumstances, including having regard to the materiality of the relevant event) terminate the Underwriting Agreement and be released from its obligations under it on the occurrence of certain events. A summary of these key termination events is set out below.

Key Underwriting Agreement termination events

The list below is not exhaustive of all of the termination events in the Underwriting Agreement and is a summary of the select events set out below only.

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The ability of the Underwriter to terminate the underwriting agreement in respect of the events set out above, in some cases, is limited to circumstances where, in the reasonable opinion of the Underwriter:

Underwriting fees

The Underwriter will be paid:

The Underwriter will also be reimbursed for certain expenses, including but not limited to legal, marketing and communication costs, printing, couriers, postage and distribution, roadshow expenses, accommodation and travel expenses.

Neither the Underwriter nor any of its related bodies corporate and affiliates, nor any of its directors, officers, partners, employees, representatives or agents have authorised or caused the issue of this Prospectus and they do not take any responsibility for this document or any action taken by you on the basis of information contained in this document. To the maximum extent permitted by law, the Underwriter and its related bodies corporate and affiliates and each of their respective directors, officers, partners, employees, representatives or agents exclude and disclaim all liability for any expenses, losses, damages or costs incurred by you as a result of your participation in the Retail Entitlement Offer and this information being inaccurate or incomplete in any way for any reason, whether by negligence or otherwise. Neither the Underwriter nor any of its related bodies corporate and affiliates, nor any of their respective directors, officers, partners, employees, representatives or agents make any recommendations as to whether you or your related parties should participate in the Retail Entitlement Offer, nor do they make any representations or warranties to you concerning this Retail Entitlement Offer or any such information, and you represent, warrant and agree that you have not relied on any statements made by either Underwriter or any of their respective related bodies corporate and affiliates or any of their respective directors, officers, partners, employees, representatives or agents in relation to the New Shares or the Retail Entitlement Offer generally.

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Persons who hold Shares as a custodian or nominee must not purport to accept, or make an application under, the Retail Entitlement Offer in respect of:

Persons acting as nominees or custodians for other persons must not take up any Entitlements on behalf of, or send any documents related to the Entitlement Offer to, any person who is an Ineligible Shareholder or any person in the United States or any person that is acting for the account or benefit of a person in the United States.

Opthea is not required to determine whether or not any registered holder or investor is acting as a nominee or custodian or the identity or residence of any beneficial owners of existing Shares or Entitlements. Where any person is acting as a nominee or custodian for a foreign person, that person, in dealing with its beneficiary, will need to assess whether indirect participation in the Entitlement Offer by the beneficiary complies with applicable laws. Opthea is not able to provide legal advice.

By submitting an Application on behalf of a beneficiary, you certify that you are the custodian or nominee for the beneficiary and the information contained in the Application Form is true and correct as at the date of the Application.

Custodians and nominees holding Shares on behalf of residents outside Australia and New Zealand may not send this Prospectus to persons, or apply for New Shares and New Options on behalf of beneficial shareholders, resident outside Australia and New Zealand. Payment by BPAY^® or such other means will be taken to constitute a representation and warranty that there has been no breach of this restriction or applicable laws.

Application for official quotation of the New Shares and New Options offered under this Prospectus has been or will be made within 7 days of the date of this Prospectus.

If the New Shares or New Options are not admitted to official quotation by ASX before the expiration of three months after the date of this Prospectus, or such period as varied by ASIC, the Company will not issue any New Shares or New Options and will repay all Application Monies for the New Shares within the time prescribed under the Corporations Act, without interest.

The fact that ASX may grant official quotation to the New Shares and New Options is not to be taken in any way as an indication of the merits of the Company or the New Shares and New Options now offered for subscription.

The issue of New Shares and New Options under the Retail Entitlement Offer will take place as soon as practicable after the Closing Date of the Retail Entitlement Offer. The Company expects that the New Shares and New Options will be issued on Thursday, 21 September 2023. It is expected that New Shares and New Options issued under the Retail Entitlement Offer will

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commence trading on a normal settlement basis on ASX on Friday, 22 September 2023. Holding statements are expected to be dispatched on or around Monday, 25 September 2023. These dates are subject to change at the absolute discretion of the Company.

Pending the issue of the New Shares and New Options or payment of refunds under this Prospectus, all Application Monies will be held by the Company in trust for the Applicants in a separate bank account as required by the Corporations Act. The Company will be entitled to retain all interest that accrues on the bank account and each Applicant waives the right to claim interest.

If an Application is not completed correctly or if the accompanying payment is for the wrong amount, the Company may, in its absolute discretion, still treat the Application to be valid. The Company’s decision to treat an Application as valid, or how to construe, amend or complete it, will be final.

Refunds under the Retail Entitlement Offer may be paid under various circumstances. If a refund is made, payment will be by cheque mailed to your address as shown on the Company’s share register or by deposit into your previously nominated bank account. You will not receive any interest on funds refunded to you.

No brokerage, commissions or other transaction costs will be payable by Eligible Shareholders in respect of the Application for, and allotment of, New Shares or New Options under the Retail Entitlement Offer.

The Company may modify or terminate the Retail Entitlement Offer at any time including closing the Retail Entitlement Offer early. The Company will notify the ASX of any modification to, or termination of, the Retail Entitlement Offer. The omission to give notice of any modification to, or termination of, the Retail Entitlement Offer or the failure of ASX to receive such notice will not invalidate the modification or termination.

The Company may settle in any manner it thinks fit, any difficulties, anomalies or disputes which may arise in connection with, or by reason of, the operation of the Retail Entitlement Offer, whether generally or in relation to any participant or application, and the decision of the Company will be conclusive and binding on all participants and other persons to whom the determination relates.

The Company reserves the right to waive strict compliance with any provision of the terms and conditions of this Prospectus. The powers of the Company under this Prospectus may be exercised by the Directors or any delegate of the Directors.

The New Shares to be issued under the Retail Entitlement Offer are of the same class and will rank equally in all respects with the Existing Shares on issue. The rights and liabilities attaching to New Shares are further described in Section 6.5.

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Shares issued on exercise of the New Options will rank equally in all respects with the Existing Shares on issue. The rights and liabilities attaching to New Options are further described in Section 6.6.

The Company operates an electronic CHESS sub-register and an electronic issue sponsored sub- register. These two sub-registers will make up the Company’s register of Securities.

The Company will not issue a share certificate to a security holder. Rather, a holding statement (similar to a bank statement) will be dispatched to security holders as soon as practicable after issue of the New Shares and New Options the subject of the Retail Entitlement Offer. The holding statement will be sent either by CHESS (if the security holder elects to hold the New Shares and New Options on the CHESS sub-register) or by the Company’s Share Registry (if the security holder elects to hold the New Shares and New Options on the issuer sponsored sub-register). The statement will set out details of the New Shares and New Options issued under this Prospectus and the Holder Identification Number (if the security holder elects to hold the New Shares and New Options on the CHESS sub register) or Shareholder Reference Number (if the security holder elects to hold the New Shares and New Options on the issuer sponsored sub-register). Updated holding statements will also be sent to each security holder following the month in which the balance of their security holding changes, and also as required by the ASX Listing Rules and the Corporations Act.

It is the responsibility of all investors to satisfy themselves of the particular taxation treatment that applies to them in relation to the Retail Entitlement Offer, by consulting their own professional tax advisors. The Company and the Directors do not accept any liability or responsibility in respect of the taxation consequences of the matters referred to in this Prospectus.

This Prospectus is important and should be read in its entirety. Persons who are in any doubt as to the course of action to be followed should consult their stockbroker, solicitor, accountant or other professional advisor without delay.

Under this Prospectus, participants in the Placement and the Institutional Entitlement Offer will be issued 1 Institutional Option for every 2 New Shares to be issued to them under the Placement and/or the Institutional Entitlement Offer (as applicable) on the same terms as the New Options.

The Institutional Options will be issued for nil consideration.

The Institutional Option Offer is scheduled to close at 5.00pm (Melbourne time) on Thursday, 14 September 2023.

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The Company reserves the right to:

at any time by making an announcement to the ASX.

Participation in the Institutional Option Offer is only open to participants in the Placement and/or the Institutional Entitlement Offer. Participants will receive 1 Institutional Option for every 2 New Shares issued to them under the Placement and/or the Institutional Entitlement Offer (as applicable).

If you are in any doubt about the Institutional Option Offer, or how participation will affect you, you should seek independent financial and taxation advice.

To participate in the Institutional Option Offer, an Applicant represents and warrants that:

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Please also see Section 6.3 for further information.

No action is required from participants in the Placement and the Institutional Entitlement Offer to take up Institutional Options under the Institutional Option Offer.

If you are issued Institutional Options under the Institutional Option Offer, you:

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The Institutional Option Offer is not underwritten.

Application for official quotation of the Institutional Options offered under this Prospectus has been or will be made within 7 days of the date of this Prospectus.

If the Institutional Options are not admitted to Official Quotation by ASX before the expiration of three months after the date of issue of this Prospectus, or such period as varied by ASIC, the Company may not issue any Institutional Options.

The fact that ASX may grant Official Quotation to the Institutional Options is not to be taken in any way as an indication of the merits of the Company or the Institutional Options now offered for subscription.

The issue of Institutional Options under the Institutional Option Offer will take place as soon as practicable after the Closing Date of the Retail Entitlement Offer and at the same time as the issue of New Options. The Company expects that the Institutional Options will be issued on Thursday, 21 September 2023. It is expected that Institutional Options issued under the Institutional Option Offer will commence trading on a normal settlement basis on ASX on Friday, 22 September 2023. Holding statements are expected to be dispatched on or around Monday, 25 September 2023. These dates are subject to change at the absolute discretion of the Company.

The Company may modify the Institutional Option Offer at any time. The Company will notify the ASX of any modification to the Institutional Option Offer. The omission to give notice of any modification to the Institutional Option Offer or the failure of ASX to receive such notice will not invalidate the modification.

The Company may settle in any manner it thinks fit, any difficulties, anomalies or disputes which may arise in connection with, or by reason of, the operation of the Institutional Option Offer, whether generally or in relation to any participant, and the decision of the Company will be conclusive and binding on all participants and other persons to whom the determination relates.

The Company reserves the right to waive strict compliance with any provision of the terms and conditions of this Prospectus. The powers of the Company under this Prospectus may be exercised by the Directors or any delegate of the Directors.

The primary purpose of the Entitlement Offer is to raise approximately $70.0 million.

The total funds raised from the Entitlement Offer and Placement of up to $80.0 million (noting that the Company has the ability to increase the size of the Placement in its sole discretion) are intended to be used by Opthea to continue advancing the clinical development of OPT-302 for the treatment of wet AMD, including to progress the Phase 3 clinical program and for general corporate purposes, as well as the other purposes described in this Prospectus.

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Please refer to Section 6.10 for further details relating to the estimated expenses of the Entitlement Offer and the Placement.

The principal effects of the Entitlement Offer and the Placement, assuming $80.0 million is raised under the Placement and the Entitlement Offer, will:

Note that no consideration is expected to be received initially by the Company on the issue of the Options. There is no certainty that all or some of the Options will be exercised and additional Shares issued as a result and, consequently, no certainty that the Company will receive proceeds from the exercise of the Options.

The pro forma preliminary unaudited balance sheet for the Company as at 30 June 2023 has been prepared based on the accounting policies normally adopted by the Company. The pro forma preliminary unaudited balance sheet represents preliminary estimated unaudited financial information and remains subject to the completion of management’s and our audit and risk committee’s reviews and other financial closing processes.

The pro forma preliminary unaudited preliminary balance sheet has not been prepared on a fully diluted basis meaning that it assumes none of the Options to be issued under this Prospectus have been exercised.

The pro forma preliminary unaudited balance sheet has been prepared to provide investors with information on the assets and liabilities of the Company and pro forma assets and liabilities of the Company as noted below. The historical and pro forma financial information is presented in abbreviated form, insofar as it does not include all of the disclosures required by the Australian Accounting Standards applicable to annual financial statements.

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Note:

The pro forma balance sheet gives effect to the following assumptions:

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Investors should note that the provision of the additional funding of US$50 million under the DFA is at the discretion of the co-investor of Carlyle and Abingworth and is subject to their final due diligence and approvals, appropriate documentation, and compliance with closing conditions. There can be no assurance that the due diligence will be completed to the satisfaction of the co-investor of Carlyle and Abingworth, that the closing terms and conditions will be satisfied or that the company will ultimately receive the additional $50 million. Please refer to Section 5, ‘Risk Factors’.

For the year ended June 30, 2023:

Basis of preparation

The basis of preparation for the historical financial information is in accordance with the Company’s accounting policies, as described in its financial reports, and the recognition and measurement principles of the Australian Accounting Standards.

The historical financial information is based on the unaudited balance sheet as of 30 June 2023.

The stated basis of preparation for the pro forma historical financial Information is in a manner consistent with the recognition and measurement principles of the Australian Accounting Standards applied to the historical financial information and the events or transactions to which the pro forma adjustments relate, as above below, as if those events or transactions had occurred as of 30 June 2023.

Throughout this Prospectus, we have presented certain preliminary estimated unaudited financial results and other data as of and for the fiscal year ended June 30, 2023, including preliminary estimated cash and cash equivalent amounts as of June 30, 2023. The estimated results are not a comprehensive statement of our results as of and for the fiscal year ended June 30, 2023, and our actual results may differ materially from these preliminary estimated results. Our actual results remain subject to the completion of management’s and our audit and risk committee’s reviews and our other financial closing processes. During the course of the preparation of our consolidated financial statements and related notes and the completion of the audit for the fiscal year ended June 30, 2023, additional adjustments to the preliminary estimated financial information presented in this presentation may be identified, and our final results for these periods may vary from these preliminary estimates.

The preliminary estimated unaudited financial and other data contained in this Prospectus have been prepared in good faith by, and are the responsibility of, management based upon our internal reporting as of and for the fiscal year ended June 30, 2023. Our independent registered public accounting firm, has not audited, reviewed, compiled or performed any procedures with respect to such preliminary data. Accordingly, our independent registered public accounting firm does not express an opinion or any other form of assurance with respect thereto.

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The effect of the Entitlement Offer and the Placement (assuming an $80.0 million Capital Raising) on the Company’s capital structure is set out in the table below.

Note:

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Based on publicly available information as at the date of this Prospectus, the following Shareholders (together with their associates) have a relevant interest in 5% or more of the Shares on issue:

In summary, section 606 of the Corporations Act provides that a person cannot acquire a ‘relevant interest’ (i.e. a controlling interest, whether formal or informal) in the issued voting shares of a company which has more than 50 members or is publicly listed if, because of the transaction in relation to securities, a person’s ‘voting power’ in the company increases from 20% or below to more than 20%, or from a starting point that is above 20% and below 90% unless a relevant exception applies. Item 13 of section 611 of the Corporations Act provides an exception to the takeover restrictions where a person underwrites or sub-underwrites an issue of securities under a prospectus or other disclosure document, and where the prospectus discloses the effect that this would have on the person’s voting power in the company.

As at the date of its last substantial shareholder filing, Regal holds 20.63% voting power in the Company. Regal has entered into a sub-underwriting arrangement with the Underwriter with respect to 81.8% of the New Shares to be issued under the Retail Entitlement Offer (Sub-underwriting Agreement).

Regal will receive 1.5% of the amount underwritten for sub-underwriting the Retail Entitlement Offer.

There are no significant events that could lead to the Sub-Underwriting Agreement being terminated, other than termination of the Underwriting Agreement between the Company and the Underwriter (in circumstances summarized above).

Through its participation in the Placement and Institutional Entitlement Offer, and any subscription of New Shares as a sub-underwriter of the Retail Entitlement Offer, it is likely that the percentage shareholding of Regal will increase. It is not possible to determine at this stage the extent of that increase and Regal will need to comply with the provisions of Chapter 6 of the Corporations Act. However, the Company does not expect any increase in the percentage shareholding of Regal to have a material effect on the control of the Company.

As with any share investment, there are risks associated with an investment in the Company. The numerous risk factors are both of a specific and general nature. Some can be mitigated by the use of safeguards and appropriate systems and controls, but some are outside the control of the Company and cannot be mitigated.

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This Section 5 identifies and highlights some of the risks that potential investors should consider prior to entering into the investment opportunity referred to in this Prospectus. However, the following is not, and does not purport to be, a comprehensive statement of all relevant risks and is not listed in order of importance. Potential investors should seek their own financial or other professional advice in relation to the risks and must make their own assessment regarding an investment in the Company.

Opthea’s activities will require substantial expenditures. Opthea’s losses from operations, including from clinical trial activities, and negative cash flows, raise substantial doubt about the ability for Opthea to continue as a going concern without additional capital raising activities. While Opthea expects that the proceeds of the Offer, together with additional funding expected under the DFA of US$35 million due under the DFA by December 31, 2023, the possible increased funding under the DFA of US$50m milliona and cash on hand, will provide funding to progress the activities set out in this Prospectus, such proceeds will not be sufficient to fully fund all anticipated costs of the Phase 3 clinical trials. In addition, Opthea’s forecast of its cash runway, following receipt of the proceeds from the Offer and under the DFA, is subject to a number of assumptions, including the timing of completion of Phase 3 clinical trial patient enrollment and CRO and labor costs. Although a co-investor of Carlyle and Abingworth has indicated its intent to provide Opthea additional funding of US$50 million under the DFA, this is subject to final due diligence and approvals, appropriate documentation and compliance with closing conditions and there is no assurance that this funding will be received or the timing of receipt of such funding. Estimated patient enrollment timing set forth in this Prospectus is primarily based on Opthea’s monthly enrollment rates for its Phase 3 clinical trials, which timing has in the past significantly fluctuated from prior estimates, including due to factors outside Opthea’s control. CRO and related costs for the Phase 3 clinical trials have also significantly fluctuated from estimates in the past, including factors outside Opthea’s control. If patient enrollment continues to be delayed in the future, or if any additional factors cause the Phase 3 clinical trials to be further delayed or more costly, then Opthea will need to obtain additional financing earlier than the third quarter of calendar year 2024. In addition, if Opthea is unable to complete the Offer as contemplated in this Prospectus or obtain the increased US$50 million of funding under the DFA, then Opthea will need to seek additional capital from other sources, which may not be available on a timely basis or at all. In such case, Opthea could be forced to delay, limit or terminate its operations, liquidate all or a portion of its assets and/or seek insolvency protection in the near term. Opthea’s failure to raise capital, if and when needed, could delay or suspend Opthea’s business strategy and could have a material adverse effect on Opthea’s activities. If additional funds are raised by issuing equity, this may result in additional dilution to the Shareholders. The pricing of future security issues will also depend on the results of Opthea’s scientific research projects, market factors, demand for securities and the need for capital. If Opthea is unable to secure funding in the short term, there is a risk that Opthea will not be able to continue operating.

Opthea has entered into an underwriting agreement with MST Financial Services Pty Ltd (Underwriter). The Underwriter has agreed to act as sole lead manager in relation to the Placement, and sole lead manager and underwriter in relation to the Entitlement Offer, subject to certain terms and conditions. Details of the fees payable to the Underwriter are included in the Appendix 3B released to ASX on the date of this Prospectus and above in Section 2.12. If certain customary conditions are not satisfied or certain customary termination events occur, then the Underwriter may terminate the Underwriting Agreement. A summary of the events which may trigger termination of the Underwriting Agreement is set out in Section 2.12.

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Opthea also gives certain representations, warranties and undertakings to the Underwriter and an indemnity to the Underwriter and its respective affiliates and related bodies corporate and their respective directors, officers, employees, partners and agents subject to certain limited exceptions.

If the Underwriting Agreement is terminated by the Underwriter, Opthea would need to find alternative financing to meet its future funding requirements. There is no guarantee that alternative funding could be sourced, either at all or on satisfactory terms and conditions. See also the ‘Future capital requirements’ disclosure above. Termination of the Underwriting Agreement could materially adversely affect Opthea’s business, cash flow, financial condition and results of operations.

We are highly reliant on the funding under the DFA including the third tranche of $35 million expected before December 31, 2023, and the potential increase in funding of US$50 million by a new co-investor of Carlyle and Abingworth (see below for further details). The DFA contains several terms that require compliance by the company in conduct of the study including the governance by a Joint Steering Committee (“JSC”) for changes in the original protocols, study design or timelines. Modifications require JSC approval and it will be difficult for the company to make modifications on their own. The DFA contains terms that require compliance by the company to maintain a minimum cash balance and to provide a notice to Ocelot (the SPV established by Carlyle and Abingworth for the purposes of providing funding to Opthea) in the event it anticipates a “Going Concern” opinion in its annual financial statements or that it does not have sufficient cash to fund its operations for the next six months. The termination provisions in the DFA on the part of Ocelot are extensive and give Ocelot a wide range of conditions to terminate the agreement. In the event of termination, unless mutual or for breach by Carlyle and Abingworth, amounts owed by the company will be multiples of the invested capital to date. As of June 30, 2023, Ocelot has invested $85 million. A new co-investor of Carlyle and Abingworth intends to participate in a funding under the DFA of US$50 million to increase total DFA funding from $120 million to $170 million, which is subject to the co-investor’s final due diligence and approvals, appropriate documentation and compliance with closing conditions. There can be no assurance that Carlyle and Abingworth will increase the funding by $50 million. The third tranche of $35 million is due under the terms of the DFA before December 31, 2023, however, in the event the $35 million is not paid it would be considered a Fundamental Material Breach of the DFA by Carlyle and Abingworth. Under a Fundamental Material Breach of the DFA, Opthea has limited recourse but would have the ability to terminate the DFA. Termination by Opthea for lack of payment of the $35 million would relieve Opthea from any repayments under the DFA. Failure to receive the third tranche of $35 million or the increased funding of $50 million would have a negative impact on our cash runway and our ability to complete enrollment in the ongoing trials. See Risks noted above under ‘Future capital requirements’.

The Opthea business model requires ongoing re-investment into clinical trials with no revenues currently contracted. As such, Opthea will continue to rely upon cash, raised through equity or debt, to fund the business as an on-going concern, including in respect of its Phase 3 clinical trials. Any unforeseen events which restrict the ability of Opthea to access capital is likely to affect Opthea’s ability to become profitable in future.

Clinical trials are inherently risky, and may prove unsuccessful or non-efficacious, impracticable or costly, which may impact profitability and commercial potential. Difficulties in enrolling patients in clinical trials may cause delays to clinical trial schedules. Enrollment has been challenged, and may be challenged in the future, in part by the Covid-19 pandemic, supply chain issues, global and regional inflation, national and local recessions, hiring qualified staff at sites, Opthea’s CRO and distribution locations, local regulatory approvals, importation and custom requirements and administrative delays. Failure, or negative or inconclusive results, can occur at many stages in development, and the results of earlier clinical trials are not necessarily predictive of future results and data from clinical trials to date may not be indicative of results obtained when these trials are completed or in later-stage trials. Further, masked data from patients in Opthea’s Phase 3 clinical trials may not be consistent with

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topline results which are subject to additional analysis once unmasked. A critical trial may fail to meet its primary or secondary endpoints and as a result inhibit product development, prevent regulatory requirements being met for marketing approval and restrict successful commercialisation. In addition, data obtained from trials is susceptible to varying interpretations, and regulators may not interpret the data as favourably as Opthea, which may delay, limit or prevent regulatory approval.

OPT-302 may fail to demonstrate a safety profile or sufficient evidence of therapeutic efficacy in future clinical studies to support its ongoing clinical development. In addition, the ability to recruit wet AMD patients into future clinical studies, or secure clinical locations in which to conduct those studies, may not occur at a sufficient rate to maintain program timelines.

Opthea maintains sensitive clinical data. Opthea may be subject to a cyber security attack or data breaches by employees or external parties with either permitted or unauthorized access. There is therefore a risk that sensitive data may be exposed to the public or be permanently lost. A cyber security attack or data breach may also have implications for Opthea’s obligations under any relevant data protection or privacy legislation. Failure to comply with such legislation or regulations can result in penalties, negative publicity and damage to its brand and reputation.

Opthea’s future success is dependent on the performance of OPT-302 in clinical trials and whether it proves to be a safe and effective treatment. OPT-302 is an experimental product in clinical development and product commercialisation resulting in potential product sales and revenues is likely to be years away, if ever, and there is no guarantee that it will be successful. OPT-302 requires additional research and development, including ongoing clinical evaluation of safety and efficacy in clinical trials and regulatory approval prior to marketing authorisation. Drug development is associated with a high failure rate and until Opthea is able to provide further clinical evidence of OPT-302’s ability to improve outcomes in patients with eye disease, the future success of the product developed remains speculative. Research and development risks include uncertainty of the outcome of results, difficulties or delays in development and general uncertainty around the scientific development of novel pharmaceutical products and any of these risks, if they were to materialize, could impact Opthea’s progress and could have a material adverse effect on Opthea’s future financial performance.

Opthea operates within a highly regulated industry, relating to the manufacture, distribution and supply of pharmaceutical products. There is no guarantee that Opthea will obtain or maintain the required approvals, licenses and registrations from all relevant regulatory authorities in all jurisdictions in which it operates. Further clinical trials may be delayed and Opthea may incur further costs if the Food and Drug Administration (FDA) and other regulatory agencies observe deficiencies that require resolution or request additional studies be conducted in addition to those that are currently planned. Furthermore Opthea is exposed to the risk of changes to existing, or the introduction of new, government policies, regulations and legislation in all jurisdictions in which it operates. A failure to obtain or maintain any required approvals, licenses and registrations or any change in regulation may adversely affect Opthea’s ability to commercialise and manufacture its treatments.

Opthea may, from time to time, consider acquisition, licensing, partnership or other corporate opportunities for Opthea’s development programs. There can be no assurance that any such acquisition, licensing, partnership or corporate opportunities can be concluded on terms that are, or are believed by Opthea to be, commercially acceptable. In the case of licensing and partnership opportunities, even if such terms are agreed there is a risk that the performance of distributors and the delivery of contracted outcomes by collaborators will not occur due to a range of unforeseen factors relating to environment, technology and market conditions.

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Future success will also depend on Opthea’s ability to achieve market acceptance and attract and retain customers, which includes convincing potential consumers and partners of the efficacy of Opthea’s products and Opthea’s ability to manufacture a sufficient quantity and quality of products at a satisfactory price.

Opthea relies on effective information technology, software, data centres and communication systems. There is a risk that these systems may be adversely affected by disruption, failure, service outages or data corruption that could occur as a result of computer viruses, “bugs” or “worms”, malware, internal or external misuse by websites, cyber-attacks or other disruptions including natural disasters, power outages or other similar events. Opthea may be significantly impacted by disruption to any of these systems or platforms.

The biotechnology and pharmaceutical industries are intensely competitive and subject to rapid and significant technological change, in Australia, the United States and elsewhere, and there are no guarantees about Opthea’s ability to successfully compete. Opthea’s products may compete with existing alternative treatments that are already available to customers. In addition, a number of companies, both in Australia and internationally, are pursuing the development of products that target wet AMD and DME. Some of these companies may have, or may develop, technologies superior to Opthea’s own technology. Some competitors of Opthea may have substantially greater financial, technical and human resources than Opthea does, as well as broader product offerings and greater market and brand presence. Opthea’s services, expertise or products may be rendered obsolete or uneconomical or decrease in attractiveness or value by advances or entirely different approaches developed by either Opthea or its competitors.

Securing rights in technology and patents is an integral part of securing potential product value in the outcomes of biotechnology research and development. Competition in retaining and sustaining protection of technology and the complex nature of technologies can lead to patent disputes.

Opthea’s success depends, in part, on its ability to obtain patents, maintain trade secret protection and operate without infringing the proprietary rights of third parties. Because the patent position of biotechnology companies can be highly uncertain and frequently involves complex legal and factual questions, neither the breadth of claims allowed in biotechnology patents nor their enforceability can be predicted. There can be no assurance that any patents which Opthea may own, access or control will afford Opthea commercially significant protection of its technology or its products or have commercial application, or that access to these patents will mean that Opthea will be free to commercialize its drug candidates.

The granting of a patent does not guarantee that the rights of others are not infringed or that competitors will not develop technology or products to avoid Opthea’s patented technology. Patenting strategies do not cover all countries which may lead to generic competition arising in those markets.

Scale-up of OPT-302 manufacture to support Phase 3 clinical studies has been completed but the process is required to be validated. Process performance qualification or “PPQ” will need to be completed as part of the filing for marketing approval. As such, there is a risk that the PPQ may present technical difficulties. Technical difficulties could include the inability to generate material that meets regulatory specifications for human administration or the product yield from manufacturing batches may be insufficient to conduct the clinical studies and support commercialization as currently planned. Any unforeseen difficulty relating to manufacturing, including changes in methods of product candidate manufacturing or formulation, disruption to supply, shortages of input materials or changes to arrangements with, or capacity of, any third-party manufacturers, may negatively impact Opthea’s ability to generate profit in the future.

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OPT-302 has not been approved for commercial sale, and Opthea expects it to be several years before OPT-302 is approved, if ever, and Opthea is able to commence sales of OPT-302. If OPT-302 is approved for commercial sale, Opthea’s commercialization expenses will increase significantly as it establishes sales, marketing, distribution, manufacturing, supply chain and other commercial infrastructure. In addition, OPT-302 may not achieve adequate market acceptance among physicians, patients, healthcare payors and others in the medical community necessary for commercial success.

Opthea’s business was and may in the future be negatively affected by the effects of health epidemics in regions where Opthea or third parties on which Opthea relies have significant manufacturing facilities, concentrations of clinical trial sites or other business operations. Health epidemics in regions where Opthea has concentrations of clinical trial sites or other business operations could negatively affect its business, including by causing significant disruption in the operations of third-party manufacturers and CROs upon whom Opthea relies (for example, Covid-19 negatively impacted Opthea’s ability to initiate clinical trial sites, maintain patient enrollment and enroll new patients.

Opthea is unable to predict the risk of financial failure or default by a participant in any joint venture to which Opthea may become a party or the insolvency or managerial failure by any of the contractors used by Opthea in any of its activities or the insolvency or other managerial failure by any of the other service providers used by Opthea for any activity. Opthea may engage with various third parties to assist with different stages of the research and development process, including agents, suppliers, distributors and contractors, and there is no guarantee that these third parties will comply with their respective contractual obligations. Transition of certain of these third parties could cause delay or disruption in the clinical trials. This could adversely impact Opthea’s progress and cause delays in or impede research or production, or result in cost increases.

Opthea is reliant on key personnel it employs or engages. Loss of such personnel may have a material adverse impact on the performance of Opthea. In addition, recruiting qualified personnel is critical to Opthea’s success. This includes attracting and retaining staff with sufficient skills to develop intellectual property. As Opthea’s business grows and progresses to Phase 3 development, it will require additional key staff for clinical development operations as well as additional key financial and administrative personnel. There can be no assurance that Opthea will be successful in attracting and retaining qualified personnel. The loss of key personnel or the inability to attract suitably qualified additional personnel could have a material adverse effect on Opthea’s financial performance.

Although Opthea maintains insurance to protect against certain risks in such amounts as it considers to be reasonable, its insurance will not cover all the potential risks associated with its operations and insurance coverage may not continue to be available, commercially acceptable, or may not be adequate to cover any resulting liability. It is not always possible to obtain insurance against all such risks and Opthea may decide not to insure against certain risks because of high premiums or other reasons.

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Serious or unexpected health, safety or efficacy concerns with products may expose Opthea to reputational harm or reduced market acceptance of its products, and may lead to product recalls and/or product liability claims and resulting liability, and increased regulatory reporting. There can be no guarantee that unforeseen adverse events or manufacturing defects will not occur. Opthea may seek to obtain product liability insurance at the appropriate time in order to seek to minimise its liability to such claims, however there can be no assurance that adequate insurance coverage will be available at an acceptable cost. Any health, safety or efficacy concerns are likely to lead to reduced customer demand and impact on the potential future profitability of Opthea.

In the ordinary course of conducting its business, Opthea is exposed to potential litigation and other proceedings, including through claims of breach of agreements, intellectual property infringement or in relation to employees (through personal injuries, occupational health and safety or otherwise). If such proceedings were brought against Opthea, it could incur considerable defence costs (even if successful), with the potential for damages and costs awards against Opthea if it were unsuccessful, which could have a significant adverse financial impact on Opthea’s business. Changes in laws can heighten litigation risk (for example, antitrust and intellectual property). Circumstances may also arise in which Opthea, having received legal advice, considers that it is reasonable or necessary to initiate litigation or other proceedings, including for example to protect its intellectual property rights. There has been substantial litigation and other proceedings in the pharmaceutical industry, including class actions from purchasers and end users of pharmaceutical products.

The market price of Opthea shares will fluctuate due to various factors, many of which are non-specific to Opthea and beyond the control of Opthea, including recommendations by brokers and analysts, Australian and international general economic conditions, inflation rates, interest rates, changes in government, fiscal, monetary and regulatory policies, global geo-political events and hostilities and acts of terrorism, and investor perceptions. Fluctuations such as these may adversely affect the market price of Opthea shares.

Neither Opthea nor the directors warrant the future performance of Opthea or any return on investment in Opthea.

Opthea intends to apply for quotation of the Options with seven days of this Prospectus being lodged with ASIC. ASX requires Opthea to meet certain conditions for quotation of Options as a new class on ASX. There is a risk that Opthea may not be able to meet those requirements. The fact that ASX may agree to grant official quotation of the Options is not to be taken in any way as an indication of the merits of Opthea or its securities. If Opthea’s application for the Options to be quoted on ASX is granted, the trading price of the Options may be affected by the ongoing performance, financial position, and solvency of Opthea. Should the ASX grant official quotation of the Options, the liquidity of trading in Options on the ASX may be limited at times and may affect an eligible participant’s ability to buy or sell Options. In addition, Opthea’s share price may not exceed the exercise price of the Options during the exercise period. In such circumstances the Options lapse without any value being realized.

Investors who do not participate in the Retail Entitlement Offer, or do not take up all of their entitlement under the Retail Entitlement Offer, will have their percentage security holding in Opthea diluted (in addition to the dilution resulting from the Placement). In addition, Opthea’s need to raise additional capital in the future in order to meet its operating or financing requirements, including by way of additional borrowings may change over time. Future equity raisings or equity funded acquisitions may dilute the holdings of particular shareholders to the extent that such shareholders do not subscribe for additional equity, or are otherwise not invited to subscribe for additional equity.

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Opthea is exposed to economic factors in the ordinary course of business. A number of economic factors / conditions, both Australian and global, affect the performance of financial markets generally, which could affect the price at which Opthea shares trade on ASX. Among other things, adverse changes in macroeconomic conditions, including movements on international and domestic stock markets, interest rates, exchange rates, cost and availability of credit, general consumption and consumer spending, input costs, employment rates and industrial disruptions, inflation and inflationary expectations and overall economic conditions, economic cycles, trade tarrifs and restrictions, investor sentiment, political events and levels of economic growth, both domestically and internationally, as well as government taxation, fiscal, monetary, regulatory and other policy changes may affect the demand for, and price of, Opthea shares and adversely impact Opthea’s business, financial position and operating results. Trading prices can be volatile and volatility can be caused by general market risks such as those that have been mentioned. New Shares in Opthea may trade at or below the price at which they commence trading on ASX including as a result of any of the factors that have been mentioned, and factors such as those mentioned may also affect the income, expenses and liquidity of Opthea. Additionally, the stock market can experience price and volume fluctuations that may be unrelated or disproportionate to the operating performance of Opthea.

Future changes in Australian taxation law, including changes in interpretation or application of the law by the courts or taxation authorities in Australia, may affect taxation treatment of an investment in Opthea shares, or the holding and disposal of those shares. Further, changes in tax law, or changes in the way tax law is expected to be interpreted, in the various jurisdictions in which Opthea operates, may impact the future tax liabilities of Opthea.

Opthea projects that it will receive material cash refunds under the Research and Development Tax Incentive scheme (the “Scheme and R&D Tax Credits”) to offset the costs of its clinical programs and other qualifying expenditure, incurred both in Australia and overseas. The assumptions underlying Opthea’s projected Scheme and R&D Tax Credits are based on actual amounts received for the 2022 financial year as a proportion of qualifying expenditure under the scheme. The Commonwealth Government and/or the Australian Taxation Office could change the rules of the regulatory regime with the effect that future amounts paid to Opthea as a proportion of its expenses could be materially lower than assumed in the Company’s projections. Any rule changes made that materially reduce the amount Opthea was able to claim under the scheme would have a material effect on the cash flows of the Company. Opthea believes that it is not a passive foreign investment company (PFIC) for U.S. federal income tax purposes for its current taxable year and it expects that it will likely not be a PFIC in the foreseeable future, although there can be no assurance in this regard and this determination depends on legal and factual considerations that cannot be predicted.

Opthea prepares its general purpose financial statements in accordance with Australian International Financial Reporting Standards (AIFRS) and the Corporations Act 2001 (Cth), which may differ significantly from the accounting standards applied by other companies (such as U.S. GAAP). Australian Accounting Standards are subject to amendment from time to time, and any such changes may impact on Opthea’s statement of financial position or statement of financial performance.

There can be no guarantee that the assumptions and contingencies on which the forward-looking statements, opinions and estimates are based will ultimately prove to be valid or accurate. The forward-looking statements, opinions and estimates included in this Prospectus depend on various factors, including known and unknown risks, many of which are outside the control of Opthea. Actual performance of Opthea may materially differ from expected performance.

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No assurances can be given in relation to the payment of future dividends. Future determinations as to the payment of dividends by Opthea will be at the discretion of Opthea and will depend upon the availability of profits, the operating results and financial conditions of Opthea, future capital requirements, covenants in relevant financing agreements, general business and financial conditions and other factors considered relevant by Opthea. No assurance can be given in relation to the level of tax deferral of future dividends. Tax deferred capacity will depend upon the amount of capital allowances available and other factors.

Opthea will be subject to changes in laws, regulations and government policy which may affect its operations and/or financial performance. Such changes may impact income or operational expenditure. Opthea is also subject to changes in taxation regimes and Accounting Standards. There can be no assurance that such changes will not have a material adverse effect on Opthea’s business, operational performance or financial results or returns to shareholders. As noted above under ‘Taxation’, adverse changes to tax law may also reduce Opthea’s capacity to claim research and incentive grants or rebates, thereby increasing expenses and reducing Opthea’s assets.

Higher than expected inflation rates generally, or specific to the biotechnology and pharmaceuticals industry in particular, could be expected to increase operating and development costs and potentially reduce the value of future project developments. While, in some cases, such cost increases might be offset by increased selling prices, there is no assurance that this would be possible or that Opthea will be in its production and supply phase of its business when this occurs.

As the Company is admitted to the Official List, the Company is a ‘disclosing entity’ for the purposes of the Corporations Act. As such, it is subject to regular reporting and disclosure obligations. Specifically, like all listed companies, the Company is required to continuously disclose to the market any information it has which a reasonable person would expect to have a material effect on the price or the value of the Company’s securities.

Price sensitive information is publicly released through the ASX before it is disclosed to Shareholders and market participants. Distribution of other information to Shareholders and market participants is also managed through disclosure to the ASX. In addition, the Company posts information on its website after the ASX confirms an announcement has been made, with the aim of making the information readily accessible to the widest audience.

By virtue of section 713 of the Corporations Act, the Company is entitled to issue a ‘transaction- specific’ prospectus in respect of the Offers.

In general terms, a ‘transaction-specific prospectus’ is only required to contain information in relation to the effect of the issue of securities on the Company and the rights and liabilities attaching to the securities. It is not necessary to include general information in relation to all of the assets and liabilities, financial position and performance, profits and losses or prospects of the issuing company.

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This Prospectus is intended to be read in conjunction with the publicly available information in relation to the Company which has been notified to ASX and does not include all of the information that would be included in a prospectus for an initial public offering of securities in an entity that is not already listed on a securities exchange. Investors should therefore have regard to the other publicly available information in relation to the Company before making a decision whether or not to invest.

Information that is already in the public domain has not been reported in this Prospectus other than that which is considered necessary to make this Prospectus complete.

As a disclosing entity under the Corporations Act, the Company states that:

There is no information which has been excluded from a continuous disclosure notice in accordance with the ASX Listing Rules that investors or their professional advisers:

This Prospectus contains information specific to the Offers. If investors require further information in relation to the Company, they are recommended to take advantage of the opportunity to inspect or obtain copies of the documents referred to above.

The following announcements have been lodged with the ASX prior to the date of this Prospectus (and including the announcement and investor presentation relating to his Capital Raising lodged with the ASX on the date of this Prospectus) in respect of the Company since the lodgment of the annual financial report for the year ended 30 June 2022 with ASX on 30 August 2022.

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The new product design and distributions obligations under the Corporations Act (DDO Obligations) took effect from 5 October 2021. The DDO Obligations are intended to help consumers obtain appropriate financial products by requiring issuers and distributors to have a consumer-centric product. The DDO Obligations require product issuers to make publicly available a target market determination that explains the target market for certain securities, any distribution conditions and any information related to reviewing and monitoring conduct in relation to the target market determination.

The Company has prepared a target market determination in respect of the Options which is available on the Company’s website at https://opthea.com/. The Options are subject to a distribution condition that retail investors will be provided with a copy of this Prospectus and access to the target market determination before they receive Options. Investors are required self-confirm that they meet the eligibility criteria of the expected target market outlined in the target market determination.

This Prospectus does not constitute an offer of New Shares or Options in any jurisdiction in which it would be unlawful. In particular, this Prospectus may not be distributed to any person, and the Options may not be offered or sold, in any country outside Australia except to the extent permitted below.

European Union

This document has not been, and will not be, registered with or approved by any securities regulator in the European Union. Accordingly, this document may not be made available, nor may the New Shares and New Options be offered for sale, in the European Union except in circumstances that do not require a prospectus under Article 1(4) of Regulation (EU) 2017/1129 of the European Parliament and the Council of the European Union (the “Prospectus Regulation”).

In accordance with Article 1(4)(a) of the Prospectus Regulation, an offer of New Shares and New Options in the European Union is limited to persons who are “qualified investors” (as defined in Article 2(e) of the Prospectus Regulation).

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Hong Kong

WARNING: This document has not been, and will not be, registered as a prospectus under the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32) of Hong Kong, nor has it been authorised by the Securities and Futures Commission in Hong Kong pursuant to the Securities and Futures Ordinance (Cap. 571) of the Laws of Hong Kong (the “SFO”). Accordingly, this document may not be distributed, and the New Shares and New Options may not be offered or sold, in Hong Kong other than to “professional investors” (as defined in the SFO and any rules made under that ordinance).

No advertisement, invitation or document relating to the New Shares and New Options has been or will be issued, or has been or will be in the possession of any person for the purpose of issue, in Hong Kong or elsewhere that is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to New Shares and New Options that are or are intended to be disposed of only to persons outside Hong Kong or only to professional investors. No person allotted New Shares and New Options may sell, or offer to sell, such securities in circumstances that amount to an offer to the public in Hong Kong within six months following the date of issue of such securities.

The contents of this document have not been reviewed by any Hong Kong regulatory authority. You are advised to exercise caution in relation to the offer. If you are in doubt about any contents of this document, you should obtain independent professional advice.

Israel

The New Shares have not been registered, and no prospectus will be issued, under the Israeli Securities Law, 1968 (the “Securities Law”). Accordingly, the New Shares will only be offered and sold in Israel pursuant to private placement exemptions, namely to no more than 35 offerees who fall within a category of sophisticated investor as described in the First Addendum of the Securities Law.

Neither this document nor any activities related to the Offer shall be deemed to be the provision of investment advice. If any recipient of this document is not the intended recipient, such recipient should promptly return this document to the Company. This document has not been reviewed or approved by the Israeli Securities Authority in any way.

New Zealand

This document has not been registered, filed with or approved by any New Zealand regulatory authority under the Financial Markets Conduct Act 2013 (the “FMC Act”).

The New Shares and New Options are not being offered to the public within New Zealand other than to existing shareholders of the Company with registered addresses in New Zealand to whom the offer of these securities is being made in reliance on the Financial Markets Conduct (Incidental Offers) Exemption Notice 2021.

Other than in the entitlement offer, the New Shares and New Options may only be offered or sold in New Zealand (or allotted with a view to being offered for sale in New Zealand) to a person who:

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Singapore

This document and any other materials relating to the New Shares and New Options have not been, and will not be, lodged or registered as a prospectus in Singapore with the Monetary Authority of Singapore. Accordingly, this document and any other document or materials in connection with the offer or sale, or invitation for subscription or purchase, of New Shares and New Options, may not be issued, circulated or distributed, nor may the New Shares and New Options be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore except pursuant to and in accordance with exemptions in Subdivision (4) Division 1, Part 13 of the Securities and Futures Act 2001 of Singapore (the “SFA”) or another exemption under the SFA.

This document has been given to you on the basis that you are an “institutional investor” or an “accredited investor” (as such terms are defined in the SFA). If you are not such an investor, please return this document immediately. You may not forward or circulate this document to any other person in Singapore.

Any offer is not made to you with a view to the New Shares or New Options being subsequently offered for sale to any other party in Singapore. On-sale restrictions in Singapore may be applicable to investors who acquire New Shares and New Options. As such, investors are advised to acquaint themselves with the SFA provisions relating to resale restrictions in Singapore and comply accordingly.

South Africa

This document does not, nor is it intended to, constitute a prospectus prepared and registered under the South African Companies Act 2008 and may not be distributed to the public in South Africa. This document has not been registered with nor approved by the South African Companies and Intellectual Property Commission.

Any offer of New Shares and New Options in South Africa will be made by way of a private placement to, and capable of acceptance only by, investors who fall within one of the specified categories listed in section 96(1)(a) of the South African Companies Act.

An entity or person resident in South Africa may not implement participation in the offer unless (i) permitted under the South African Exchange Control Regulations or (ii) a specific approval has been obtained from an authorised foreign exchange dealer in South Africa or the Financial Surveillance Department of the South African Reserve Bank.

United Kingdom

Neither this document nor any other document relating to the offer has been delivered for approval to the Financial Conduct Authority in the United Kingdom and no prospectus (within the meaning of section 85 of the Financial Services and Markets Act 2000, as amended (“FSMA”)) has been published or is intended to be published in respect of the New Shares and New Options.

The New Shares and New Options may not be offered or sold in the United Kingdom by means of this document or any other document, except in circumstances that do not require the publication of a prospectus under section 86(1) of the FSMA. This document is issued on a

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confidential basis in the United Kingdom to “qualified investors” within the meaning of Article 2(e) of the UK Prospectus Regulation. This document may not be distributed or reproduced, in whole or in part, nor may its contents be disclosed by recipients, to any other person in the United Kingdom.

Any invitation or inducement to engage in investment activity (within the meaning of section 21 of the FSMA) received in connection with the issue or sale of the New Shares and New Options has only been communicated or caused to be communicated and will only be communicated or caused to be communicated in the United Kingdom in circumstances in which section 21(1) of the FSMA does not apply to the Company.

In the United Kingdom, this document is being distributed only to, and is directed at, persons (i) who have professional experience in matters relating to investments falling within Article 19(5) (investment professionals) of the Financial Services and Markets Act 2000 (Financial Promotions) Order 2005 (“FPO”), (ii) who fall within the categories of persons referred to in Article 49(2)(a) to (d) (high net worth companies, unincorporated associations, etc.) of the FPO or (iii) to whom it may otherwise be lawfully communicated (“relevant persons”). The investment to which this document relates is available only to relevant persons. Any person who is not a relevant person should not act or rely on this document.

United States

This document does not constitute an offer to sell, or a solicitation of an offer to buy, securities in the United States. The New Shares and New Options (as well as the shares underlying the New Options) have not, and will not be, been registered under the US Securities Act of 1933 or the securities laws of any state or other jurisdiction of the United States. Accordingly, the New Shares and New Options (as well as the shares underlying the New Options) may not be offered or sold in the United States except in transactions exempt from, or not subject to, the registration requirements of the US Securities Act and applicable US state securities laws.

The Company is not currently engaged in litigation and, as at the date of this Prospectus, the Directors are not aware of any legal proceedings pending or threatened against, or any material legal proceedings affecting, the Company.

The following is a general description of the more significant rights and liabilities attaching to the New Shares. This summary is not exhaustive. Full details of provisions relating to rights attaching to the New Shares are contained in the Corporations Act, ASX Listing Rules and the Constitution (a copy of which is available for inspection at the Company’s registered office during normal business hours).

At the date of this Prospectus, all shares are of the same class and rank equally in all respects. Specifically, the New Shares issued under this Prospectus will rank equally with the Company’s existing Shares.

Subject to any rights or restrictions, at general meetings:

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Shareholders will be entitled to dividends, distributed among members in proportion to the capital paid up or credited as paid up, from the date of payment. No dividend carries interest against the Company and the declaration of Directors as to the amount to be distributed is conclusive.

Shareholders may be paid interim dividends or bonuses at the discretion of the Directors. The Directors may set aside a sum out of the profits of the Company, as reserves, before recommending dividends of the profits.

The rights attaching to the New Shares may only be varied by the consent in writing of the holders of three-quarters of the Shares, or with the sanction of a special resolution passed at a general meeting.

New Shares can be transferred through the financial market operated by the ASX or by a proper instrument of transfer. The instrument of transfer must be in writing in a usual form or any other form approved by the Directors, and signed by or on behalf of the transferor and the transferee. Except where the operating rules of an applicable CS facility licensee, being the ASTC Operating Rules provide otherwise, until the transferee has been registered, the transferor is deemed to remain the holder of the Shares, even after signing the instrument of transfer.

In some certain prescribed circumstances, the Directors may refuse to register a transfer of New Shares.

Shareholders are entitled to be present in person, or by proxy, attorney or representative to attend and vote at general meetings of the Company.

The Directors may convene a general meeting at their discretion.

The Constitution provides for the sale of unmarketable parcels subject to any applicable laws and provided a notice is given to the relevant Shareholder stating that the Company intends to sell their relevant New Shares unless the relevant Shareholder advises the Company by a specified date that they wish to retain the Shares.

If the Company is wound up, the liquidator may with the sanction of a special resolution, divide the assets of the Company amongst Shareholders as the liquidator sees fit. The liquidator may not require a Shareholder to accept any New Shares or other securities in respect of which there is any liability.

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The Options to be issued under the Offers will be issued on the following terms and conditions:

Each Option entitles the holder to acquire by way of issue one Share on exercise of the Option.

Subject to paragraph (h) below, the exercise price of the Options will be $0.80 (Exercise Price).

Each Option will expire at 5.00pm (Melbourne time) on 31 August 2025 (Expiry Date). An Option not exercised by the Expiry Date will automatically lapse at that time at that time.

The Options are exercisable at any time on or prior to the Expiry Date (Exercise Period).

A Notice of Exercise is only effective on and from the later of the date of receipt of the Notice of Exercise and the date of receipt of the payment of the applicable Exercise Price for each Option being exercised in cleared funds (Exercise Date).

A minimum of 3,000 Options may be exercised under each Notice of Exercise. If a Shareholder holds less than 3,000 Options, all of the Options held by them must be exercised in one Notice of Exercise.

As soon as practicable after the Exercise Date, the Company will:

Shares issued on exercise of the Options will rank equally in all respects with the then issued Shares.

If at any time the issued capital of the Company is reconstructed, all rights of a holder of Options are to be changed in a manner consistent with the Corporations Act and the ASX Listing Rules at the time of the reconstruction.

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There are no participation rights or entitlements inherent in the Options and holders will not be entitled to participate in new issues of capital offered to Shareholders during the currency of the Options without exercising the Options and unless Shares have been issued in respect of the Options before the record date for determining entitlements to the issue.

There will be no change to the applicable Exercise Price of an Option or the number of Shares over which an Option is exercisable in the event of the Company making a pro rata issue of Shares or other securities to the holders of Shares (other than for a Bonus Issue).

If before the expiry of any Options, the Company makes a pro rata issue of Shares to Shareholders for no consideration (Bonus Issue), the number of Shares over which an Option is exercisable will be increased by the number of Shares which the holder would have received if the Option had been exercised before the record date for the Bonus Issue.

Holders of Options have no voting rights until the Options are exercised and Shares issued on exercise of those Options in accordance with the ASX Listing Rules.

The Options are transferable and will be quoted on the ASX.

The Options will not give any right to participate in dividends until Shares are issued pursuant to the exercise of the relevant Options.

holds, or has held within 2 years before the date of this Prospectus, any interest in the Offers or in the formation or promotion of, or in any property acquired or proposed to be acquired by, the Company in connection with its formation or promotion or the Offers.

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In the event the requisite shareholder approval is not obtained, the Company and Mr Gozlan will agree an appropriate additional amount as an alternative to the proposed issue of options.

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The relevant interests of the Directors in securities of the Company as at the date of this Prospectus are as follows:

As Chair and non-executive Director, Dr. Jeremy Levin is currently paid US$75,000 in directors fees per annum.

As a Managing Director and Chief Executive Officer, Dr. Megan Baldwin is employed under an ongoing contract and receives fixed remuneration of A$575,000 per annum.

As a non-executive Director, Dr. Susan Orr is currently paid US$50,000 in directors fees per annum. Clinical Sub Committee Chair fee of US$10,000 per annum plus US$5,000 per committee fee per annum.

As a non-executive Director, Mr Lawrence Gozlan is currently paid A$65,700 in directors fees per annum. Nominations Committee Chair fee of A$13,140 per annum plus Committee fees of A$6,570 per committee per annum.

As a non-executive Director, Mr Daniel Spiegelman is currently paid US$50,000 in directors fees per annum. Audit and Risk Committed fee of US$20,000 per annum plus US$5,000 for committee fee per annum.

As a non-executive Director, Dr. Julia Haller is currently paid US$50,000 in directors fees per annum. Committee fees of US$5,000 per annum per committee.

As a non-executive Director, Mr Quinton Oswald is currently paid US$50,000 in directors fees per annum. Remuneration Chair fee of US$10,000 per annum plus US$5,000 per committee fee per annum.

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As a non-executive Director, Mr Anshul Thakral is currently paid US$50,000 in directors fees per annum. Committee fees of US$5,000 per annum per committee.

As announced by Opthea to ASX on 9 June 2023, Opthea appointed Mr. Anshul Thakral to its board of directors. Mr. Thakral is Chief Executive Officer and Board Member of Launch Therapeutics, a clinical development company backed by funds managed by global investment firm Carlyle (NASDAQ: CG) and its life sciences franchise, Abingworth. Mr Thakral is also a director of Saama Technologies, LLC. As such, any agreements with Carlyle and Abingworth (and their special purpose vehicle Ocelot), Launch Therapeutics and Saama Technologies are considered related party arrangements.

As described in Section 6.7(c) above, Mr Lawrence Gozlan, a director of the Company, and the Company have entered into a Consultancy Agreement in respect of the provision services associated with managing and overseeing and coordinating the conduct and implementation of the Capital Raising which, in the opinion of the Directors, are outside the scope of the ordinary duties of a Director.

Chapter 6D of the Corporations Act imposes a liability regime on the Company (as the offeror of the Securities), the Directors, the persons named in the Prospectus with their consent as proposed directors, any underwriters, persons named in the Prospectus with their consent having made a statement in the Prospectus and persons involved in a contravention in relation to the Prospectus, with regard to misleading and deceptive statements made in the Prospectus. Although the Company bears primary responsibility for the Prospectus, the other parties involved in the preparation of the Prospectus can also be responsible for certain statements made in it.

Gilbert + Tobin has given and has not, before lodgement of this Prospectus, withdrawn its written consent to be named in this Prospectus as Australian legal adviser to the Company in respect of the Capital Raising in the form and context in which it is named.

Cooley LLP has given and has not, before lodgement of this Prospectus, withdrawn its written consent to be named in this Prospectus as US legal adviser to the Company in respect of the Capital Raising in the form and context in which it is named.

MST Financial Services Pty Ltd has given and has not, before lodgement of this Prospectus, withdrawn its written consent to be named in this Prospectus as lead manager of the Capital Raising and underwriter of the issue of New Shares under the Entitlement Offer in the form and context in which it is named.

Regal Funds Management Pty Ltd has given and has not, before lodgement of this Prospectus, withdrawn its written consent to be named in this Prospectus as lead manager of the Capital Raising and underwriter of the issue of New Shares under the Entitlement Offer in the form and context in which it is named.

Computershare Investor Services Pty Limited has given and has not, before lodgement of this Prospectus, withdrawn its written consent to be named in this Prospectus as share registry to the Company in respect of the Capital Raising in the form and context in which it is named.

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Each of the persons named as providing consents above:

The total expenses of the Capital Raising are estimated to be approximately $6,770,000 (excluding GST), the table below sets out the breakdown of these expenses:

The information in this Prospectus, the Offers, and the contracts formed on acceptance of the Application Form are governed by the law applicable in Victoria, Australia. Any person who applies for Securities under the Offers submits to the non-exclusive jurisdiction of the courts of Victoria, Australia.

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This Prospectus is issued by the Company and its issue has been authorised by a resolution of the Directors.

In accordance with section 720 of the Corporations Act, each Director has consented to the lodgement of this Prospectus with ASIC and has not withdrawn that consent.

Signed for and on behalf of the Company on 24 August 2023.

Dr. Jeremy Levin

Non-Executive Director and Chairman

Opthea Limited

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Definitions used in this Prospectus are as follows:

Applicant means a person who submits an Application.

Application means an application for New Shares and/or Options under this Prospectus.

Application Form means the personalised application form included in or accompanying this Prospectus for participation in the Retail Entitlement Offer.

Application Monies means monies equal to the value of New Shares at the Offer Price applied for by an Eligible Shareholder.

ASIC means the Australian Securities and Investments Commission.

ASX Listing Rules means the official listing rules of ASX Listing Rules as amended or waived.

ASX means ASX Limited ACN 008 624 691 or the financial market known as the ‘Australian Securities Exchange’ operated by it, as the context requires.

ASTC Operating Rules means the operating rules of ASTC in its capacity as a CS facility licensee, except to the extent of any relief given by ASTC in their application to the Company.

Australian Accounting Standards means the Australian accounting standards issued by the Australian Accounting Standards Board.

Board means the board of Directors of the Company.

Capital Raising means the Placement and the Entitlement Offer.

Chair means the Chair of the Board.

CHESS means Clearing House Electronic Subregister System operated by ASX Settlement Pty Limited (ABN 49 008 504 532).

Closing Date means the date that the Offers close which is 5.00pm (Melbourne time) on Thursday, 14 September 2023 or such other time and date as the Directors determine, being the last day on which Applications will be accepted.

Company or Opthea means Opthea Limited ABN 32 006 340 567.

Constitution means the constitution of the Company.

Corporations Act means the Corporations Act 2001 (Cth).

Director means a director of the Company.

Eligible Shareholder has the meaning given in Section 2.4.

Entitlement means the number of New Shares and New Options each Eligible Shareholder is offered under the Retail Entitlement Offer.

Entitlement Offer means the Retail Entitlement Offer and the Institutional Entitlement Offer.

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Existing Shares means Shares on issue at the Record Date.

Expiry Date means the expiry date of the New Options offered under this Prospectus, as defined in Section 6.6.

Ineligible Shareholder has the meaning given in Section 2.4.

Institutional Entitlement Offer means the fully underwritten pro-rata accelerated non- renounceable entitlement offer to existing institutional and sophisticated shareholders as announced by the Company to the ASX on Thursday, 24 August 2023.

Institutional Options means the Options offered under the Institutional Option Offer.

Institutional Option Offer means the offer of Institutional Options to participants in the Placement and the Institutional Entitlement Offer under this Prospectus.

New Options means the Options offered under the Retail Entitlement Offer.

New Shares means the new Shares offered under the Entitlement Offer and the Placement.

Offers means the Retail Entitlement Offer and the Institutional Option Offer.

Offer Period means the period commencing on the Opening Date and ending on the Closing Date.

Offer Price means the offer price of $0.46 per New Share under the Retail Entitlement Offer.

Official List means the official list of the ASX.

Opening Date means the opening date of the Offers.

Option means the right of the holder to be issued one new Share on payment of the applicable exercise price on the terms and conditions set out in Section 6.6.

Option Offer means the Institutional Option Offer and the offer of New Options under the Retail Entitlement Offer.

Placement means the issue of up to approximately 21.7 million New Shares to certain sophisticated and institutional investors under a placement announced by the Company to the ASX on Thursday, 24 August 2023.

Prospectus means this prospectus dated 24 August 2023 and lodged with ASIC, including any supplementary or replacement prospectus in relation to this prospectus.

Record Date means 7.00pm (Melbourne time) on Monday, 28 August 2023, being the date on which Eligible Shareholders who are permitted to participate in the Retail Entitlement Offer are determined.

Retail Entitlement Offer means the offer of New Shares (including, for the avoidance of doubt, the offer of additional New Shares under the Top-Up Facility) and New Options to Eligible Shareholders under this Prospectus.

Section means a section of this Prospectus.

Securities means the New Shares and Options offered under this Prospectus.

Share means a fully paid ordinary share in the capital of the Company.

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Share Registry means Computershare Investor Services Pty Limited ACN 078 279 277.

Shareholder means a holder of at least one Share.

Top-Up Facility has the meaning given in Section 1.

Underwriter means MST Financial Services Pty Ltd ACN 617 475 180.

US or United States means the United States of America.

US Securities Act means the United States Securities Act of 1933, as amended.

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CORPORATE DIRECTORY

Directors

Dr. Jeremy Levin (Non-Executive Director and Chairman)

Dr. Megan Baldwin (Managing Director and Chief Executive Officer)

Mr Lawrence Gozlan (Non-Executive Director)

Mr Daniel Spiegelman (Non-Executive Director)

Dr. Julia Haller (Non-Executive Director)

Dr. Susan Orr (Non-Executive Director)

Mr Quinton Oswald (Non-Executive Director)

Mr Anshul Thakral (Non-Executive Director)

Company Secretary

Ms Karen Adams (Vice President Finance and Company Secretary)

Registered Office

Level 4, 650 Chapel Street

South Yarra, Victoria 3141

Share Registry

Computershare Investor Services Pty Limited

Yarra Falls, 452 Johnston Street

Abbotsford Victoria 3067

Underwriter

MST Financial Services Pty Ltd

Level 13, 14 Martin Place

Sydney, NSW 2000

Australia Legal Adviser

Gilbert + Tobin

Level 25, 101 Collins Street

Melbourne VIC 3000

US Legal Adviser

Cooley LLP

3175 Hanover Street

Palo Alto, CA 94304-1130

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