ASX, Nasdaq and Media Release 31 August 2023 Opthea Retail Entitlement Offer Opens On Monday, 28 August 2023 OPT announced that it had successfully completed the placement and institutional entitlement offer components o

ASX, Nasdaq and Media Release

Entitlement Offer Opens

Melbourne, Australia; 31 August 2023 Opthea Limited (Opthea or the Company) (ASX:OPT; NASDAQ:OPT) is pleased to announce that

the retail component of its fully underwritten 1 for 3.07 pro-rata accelerated non-renounceable entitlement offer (Retail Entitlement Offer) of new fully paid

ordinary shares in Opthea (New Shares) and the issue of options to acquire fully paid ordinary shares in Opthea (Options) on a 1 for 2 basis to participants issued New Shares under the Retail Entitlement Offer opens today.

Opthea also advises that it will today complete dispatch of the following documents to Eligible Shareholders (as defined in Opthea s prospectus, which

was lodged with ASIC on Thursday, 24 August 2023 (Prospectus)):

including in each case, details of how to access the Prospectus.

The Prospectus contains information about the Retail Entitlement Offer of New Shares and the issue of Options on a 1 for 2 basis to participants issued

New Shares under the Retail Entitlement Offer and Opthea s preceding institutional entitlement offer and institutional placement, details of which were announced to ASX on Thursday, 24 August 2023.

As announced on Thursday, 24 August 2023, the proceeds from the capital raising will be used to advance 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.

A copy of the Prospectus is available to Eligible Shareholders at www.computersharecas.com.au/opt2023offer and a letter to retail shareholders who are

ineligible to participate in the Retail Entitlement Offer notifying them of their ineligibility to participate has also been dispatched (an example of which is attached).

Fully Underwritten Retail Entitlement Offer

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

2023. Eligible Shareholders may opt to take up all, part or none of their entitlement. Eligible 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).

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).

must be received prior to the end of the offer period in accordance with the Prospectus.

Participants in the Retail Entitlement Offer will receive 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 Retail Entitlement Offer. The offer of New Options is made under the Prospectus.

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 are set out in the Prospectus. Copies of the Prospectus are available on the ASX website and at

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 2001 (Cth).

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.

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.

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

Blueprint Life Science Group

Tel: +1 415 505 3749

Join our email database to receive

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

NOT FOR RELEASE OR DISTRIBUTION IN THE UNITED STATES

OPTHEA LIMITED (ASX:OPT) - RETAIL ENTITLEMENT OFFER NOW OPEN

On Thursday, 24 August 2023, Opthea Limited (ABN 32 006 340 567) (the Company or Opthea) announced that it was conducting an institutional

placement (Placement) to raise approximately A$10.0 million and a fully underwritten 1 for 3.07 pro rata accelerated non-renounceable entitlement offer (Entitlement Offer, together with the

Placement, the Capital Raising) of new fully paid ordinary shares in the Company (New Shares), to raise approximately A$70.0 million, in each case at a price of A$0.46 per New Share (Offer Price). Participants in the

Placement and Entitlement Offer will also be offered, for no additional consideration, 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

The Entitlement Offer comprises an institutional entitlement offer (Institutional Entitlement Offer) and an offer to eligible

retail shareholders (as defined below) (Retail Entitlement Offer) at the same Offer Price and Offer Ratio. The Placement and Institutional Entitlement Offer have closed and the results (including in relation to the increased Placement size)

were announced to ASX on Monday, 28 August 2023.

The proceeds of the Capital Raising 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. Please refer to Opthea s Announcement, Investor Presentation and Prospectus lodged with the Australian Securities Exchange (ASX) on Thursday, 24 August 2023 for further details.

The purpose of this letter is to

inform you about the Retail Entitlement Offer and to explain that if you are an eligible retail shareholder (see below), you will be able to subscribe for 1 New Share for every 3.07 existing Opthea fully paid ordinary shares (Shares)

held by you at 7:00pm (Melbourne time) on Monday, 28 August 2023 (Record Date) at the Offer Price (being the same offer price per New Share under the Placement and Institutional Entitlement Offer), while also receiving, for no

additional consideration, 1 New Option for every 2 New Shares.

New Shares issued under the Entitlement Offer will be fully paid and rank equally with

existing Shares from the date of issue.

The Entitlement Offer is fully underwritten by MST Financial Services Pty Ltd (Underwriter).

The Retail Entitlement Offer is being made by the Company pursuant to a transaction specific prospectus

which was lodged with the Australian Securities and Investments Commission (ASIC) and ASX on Thursday, 24 August 2023.

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

Shareholders who are not Eligible Shareholders are ineligible retail shareholders and are

consequently unable to participate in the Retail Entitlement Offer.

This letter is not an offer document but is a notice of some key terms and conditions of the Retail Entitlement Offer. Full details of the Retail Entitlement