NovaBridge Biosciences Supplemental and Updated Disclosures NovaBridge Biosciences (the "Company" or "we") has filed an application (the "Listing Application") with the Stock Exchange of Hong King Limited (the "Hong Kong

NovaBridge Biosciences Supplemental and Updated Disclosures

NovaBridge Biosciences (the "Company" or "we") has filed an application (the "Listing Application") with

the Stock Exchange of Hong King Limited (the "Hong Kong Stock Exchange") in connection with a proposed dual primary listing (the "Listing") of its ordinary shares (the "Shares"), with a par value US$0.0001 per

share, on the Main Board of the Hong Kong Stock Exchange together with an initial public offering of the Shares on the Hong Kong Stock Exchange ( the "Offering").

The Listing Application contains new and supplemental descriptions of certain aspects of the Company's business and financial

information as required by the Hong Kong Stock Exchange Listing Rules as well as updated disclosures of certain information previously disclosed in the Company's annual report on Form 20-F for the year

ended December 31, 2024 (the "2024 Form 20-F"). This Supplemental and Updated Disclosures exhibit sets forth such new, supplemental, and updated information and disclosures as described below.

The disclosures herein supplement, and should be read in conjunction with, the disclosures in the 2024 Form 20-F and other disclosures furnished on Form 6-K. Capitalized

terms used but not defined herein shall have the meanings ascribed thereto in the Listing Application.

There is no assurance as to if or

when the Listing and Offering will take place. This communication is neither an offer to sell nor a solicitation of an offer to buy, nor shall there be any offer, solicitation or sale of the Company's securities in any jurisdiction in which

such offer, solicitation, or sale would be unlawful.

FORWARD-LOOKING STATEMENTS

This exhibit contains certain forward-looking statements and information relating to us and our subsidiaries that are based on the beliefs of

our management as well as assumptions made by and information currently available to our management. When used in this exhibit, the words "aim," "anticipate," "believe," "could,"

"estimate," "expect," "going forward," "intend," "may," "might," "ought to," "plan," "potential," "predict,"

"project," "seek," "should," "will," "would" and the negative of these words and other similar expressions, as they relate to us or our management, are intended to identify forward-looking

statements. Such statements reflect the current views of our management with respect to future events, operations, liquidity and capital resources, some of which may not materialize or may change. These statements are subject to certain risks,

uncertainties and assumptions, including the other risk factors as described in this exhibit. You are strongly cautioned that reliance on any forward-looking statements involves known and unknown risks and uncertainties. The risks and uncertainties

facing our Company which could affect the accuracy of forward-looking statements include, but are not limited to, the following:

Subject to the requirements of applicable laws, rules and regulations, we do not have any and undertake no obligation

to update or otherwise revise the forward-looking statements in this exhibit, whether as a result of new information, future events or otherwise. As a result of these and other risks, uncertainties and assumptions, the forward-looking events and

circumstances discussed in this exhibit might not occur in the way we expect or at all. Accordingly, the forward-looking statements are not a guarantee of future performance and you should not place undue reliance on any forward-looking information.

Moreover, the inclusion of forward-looking statements should not be regarded as representations by us that our plans and objectives will be achieved or realized. All forward-looking statements in this exhibit are qualified by reference to the

cautionary statements in this section.

In this exhibit, statements of or references to our intentions or those of our Directors are

made as of the date of this exhibit. Any such information may change in light of future developments.

RECENT DEVELOPMENTS AND NO MATERIAL ADVERSE CHANGE

a new business model designed to identify and advance high-value therapeutic assets through strategic partnerships and specialized subsidiary entities. Under this model, we become a biotechnology platform company which will establish separate

subsidiaries responsible for the development of therapeutically focused assets to enhance oversight, operational focus, and risk management.

We completed the safety assessment of the dose escalation study of the Phase 1b clinical trial of givastomig as a combination therapy with

the standard of care in May 2025 and expect to announce the dose expansion data from the combination study of this Phase 1b trial in the first quarter of 2026.

On October 14, 2025, our Company entered into a Series A Preferred Stock Subscription Agreement with Visara, one of our subsidiaries

and AffaMed. Pursuant to the Series A Agreement, (i) our Company agreed to contribute cash in exchange for approximately 65% equity interest in Visara, (ii) AffaMed agreed to assign its rights and obligations related to the rights to

develop, commercialize and otherwise exploit VIS-101 and related products in all countries and territories worldwide except for Singapore, Thailand, Malaysia, Indonesia, Vietnam, the People's Republic of China, Taiwan, Macau, Hong Kong, Korea,

and India to Visara in exchange for approximately 30% equity interest in Visara. In further consideration of the Assignment, Visara also agreed to make a one-time cash payment to AffaMed. For details, see "Business - Our

Collaboration Arrangements - In-license of VIS-101."

No Material Adverse Change

After performing sufficient due diligence work which our Directors consider appropriate and after due and careful consideration, our

Directors confirm that, up to the date of this document, there has been no material adverse change in our financial or trading position or prospects since June 30, 2025, which is the end date of the periods reported on in the Accountant's

Report included in Appendix I to the Listing Application, and there is no event since June 30, 2025 that would materially affect the information as set out in the Accountant's Report included in Appendix I to the Listing

An [REDACTED] in our Shares involves various risks. You

should carefully read and consider all of the information in this document including the risks and uncertainties described below before deciding to make any [REDACTED] in our Shares.

The occurrence of any of the following events could materially and

adversely affect our business, financial condition, results of operations or prospects. If any of these events occurs, the [REDACTED] price of our Shares could decline and you may lose all or part of your [REDACTED]. You

should seek professional advice from your relevant advisers regarding your prospective [REDACTED] in the context of your particular circumstances.

RISKS RELATING TO THE DEVELOPMENT OF OUR DRUG CANDIDATES

Clinical development involves a lengthy and expensive process with an uncertain outcome, and results of earlier studies and trials may not be predictive

of future trial results.

Clinical testing is expensive and lengthy, and its outcome is inherently uncertain. While our exclusive

focus is to develop drug candidates with the potential to become novel or highly differentiated drugs globally, we cannot guarantee that we are able to achieve this for any of our drug candidates. Failure can occur at any time during the clinical

development process. The results of preclinical studies and early clinical trials of our drug candidates may not be predictive of the results of later-stage clinical trials. Drug candidates during later stages of clinical trials may fail to show the

desired results in safety and efficacy despite having progressed through preclinical studies and initial clinical trials and despite the level of scientific rigor in the study, design and adequacy of execution. In addition, there can be significant

variability in safety and/or efficacy results among different trials of the same drug candidate due to numerous factors, including demographics, differences in individual patient conditions, such as genetic differences, and other compounding

factors, such as other medications or pre-existing medical conditions.

trials we conduct, results may differ from earlier trials due to the larger number of clinical trial sites, larger number of patients enrolled and additional countries and languages involved in such trials. A number of companies in the

biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to a lack of efficacy or adverse safety profiles, notwithstanding promising results in earlier trials. We cannot guarantee that our future clinical trial

results will be favorable based on currently available clinical and preclinical data.

We depend substantially on the success of our drug candidates,

all of which are in clinical development, and our ability to identify additional drug candidates. If we are unable to successfully identify new drug candidates, complete clinical development, obtain regulatory approval or commercialize our drug

candidates, or experience significant delays in doing so, our business will be materially harmed.

Our business will depend on the

successful development, regulatory approval and commercialization of our drug candidates for the treatment of patients with our targeted indications, all of which are still in early clinical development, and other new drug candidates that we may

identify and develop. As of the Latest Practicable Date, we have open INDs with the FDA for four of our drug candidates, givastomig,

uliledlimab, ragistomig and VIS-101. However, we cannot guarantee that we will be able to obtain regulatory approvals to conduct clinical trials for our other existing drug candidates in a timely

manner, or at all. In addition, none of our drug candidates have been approved for marketing in any jurisdiction. Each of our drug candidates will require additional preclinical and/or clinical development, regulatory approvals in multiple

jurisdictions, development of manufacturing supply and capacity, substantial investment and significant marketing efforts before we generate any revenue from product sales.

The success of our drug candidates will depend on several factors, including but not limited to, successful completion of preclinical and/or

clinical trials or studies, receipt of regulatory approvals from applicable regulatory authorities for planned clinical trials, successful completion of future clinical trials or drug registrations, successful manufacturing and commercialization of

our existing drug candidates, obtaining coverage and reimbursement from third-party payors, hiring sufficient technical experts to oversee all development and regulatory activities and license renewal and meeting safety requirements.

If we do not achieve one or more of these in a timely manner or at all, we could experience significant delays in our ability to obtain

approval for our drug candidates, which would materially harm our business and we may not be able to generate sufficient revenues and cash flows to continue our operations. As a result, our financial condition, results of operations and prospects

will be materially and adversely harmed.

We face intense competition and rapid technological change and the possibility that our competitors may

develop therapies that are similar, more advanced, or more effective than ours, which may adversely affect our financial condition and our ability to successfully commercialize our drug candidates.

The biotechnology and pharmaceutical industries are intensely competitive and subject to rapid and significant technological change. While

our exclusive focus is to develop drug candidates with potential to become novel or highly differentiated drugs, we continue to face competition with respect to our current drug candidates, and will face competition with respect to any drug

candidates that we may seek to develop or commercialize in the future. Our competitors include major pharmaceutical companies, specialty pharmaceutical companies and biotechnology companies worldwide. We are developing our drug candidates for the

treatment of cancer in competition with a number of large biopharmaceutical companies that currently market and sell drugs or are pursuing the development of drugs also for the treatment of cancer. Some of these competitive drugs and therapies are

based on scientific approaches that are the same as or similar to our approach, and others are based on entirely different approaches. Potential competitors further include academic institutions, government agencies and other public and private

research organizations that conduct research, seek patent protection and establish collaborative arrangements for research, development, manufacturing and commercialization.

Many of our competitors have substantially greater financial, technical, and other resources, such as larger research and development staff

and experienced marketing and manufacturing organizations. Additional mergers and acquisitions in the biotechnology and pharmaceutical industries may result in even more resources being concentrated in our competitors. As a result, these companies

may obtain regulatory approval from the FDA or other comparable regulatory authorities more rapidly than we are able to and may be more effective in selling and marketing their products as well.

Smaller or early-stage companies may also prove to be significant competitors, particularly

through collaborative arrangements with large, established companies. Competition may increase further as a result of advances in the commercial applicability of technologies and greater availability of capital for investment in these industries.

Our competitors may succeed in developing, acquiring, or licensing on an exclusive basis, products that are more effective or less costly than any drug candidate that we may develop, or achieve earlier patent protection, regulatory approval, product

commercialization, and market penetration than we do. Additionally, technologies developed by our competitors may render our potential drug candidates uneconomical or obsolete, and we may not be successful in marketing our drug candidates against

We may not be able to identify, discover or in-license new drug candidates, and may allocate

our limited resources to pursue a particular drug candidate or indication and fail to capitalize on drug candidates or indications that may later prove to be more profitable, or for which there is a greater likelihood of success.

Although a substantial amount of our effort will focus on the continued clinical testing, potential approval, and potential