Mural Oncology Announces Entry into Agreement to be Acquired by XRA 5 Corp., a wholly owned subsidiary of XOMA Royalty for between $2.035 and $2.24 in Cash per Share

WALTHAM, Mass. and DUBLIN and EMERYVILLE, Calif., Aug. 20, 2025 (GLOBE NEWSWIRE) -- Mural Oncology plc (Nasdaq: MURA), a clinical-stage immuno-oncology company (“Mural”), and XOMA Royalty Corporation (Nasdaq: XOMA), a biotechnology royalty aggregator (“XOMA Royalty”), announced today they have entered into a definitive agreement pursuant to which XRA 5 Corp., a newly formed company wholly owned by XOMA Royalty (“Sub”), has agreed to acquire the entire issued and to be issued share capital of Mural for cash (the “Acquisition”) subject to the satisfaction of the closing conditions set out in Appendix I of this Announcement (the “Conditions”), including approval by Mural Shareholders. Following a strategic review process, the Mural board of directors (the “Mural Board”) determined the acquisition and cash offer by XOMA Royalty is in the best interests of all Mural Shareholders and has approved the Acquisition. The Acquisition has also been approved by the boards of directors of XOMA Royalty and Sub.

Under the terms of the Acquisition and subject to certain conditions, at closing, each Mural Shareholder (i) would receive a base cash price of $2.035 per share (the “Base Price Per Share”) and (ii) may receive an additional cash amount per share of up to $0.205 (the “Additional Price Per Share”) which would be calculated on the basis of the amount by which Mural’s Closing Net Cash on the Closing Net Cash Date exceeds its Estimated Closing Net Cash (the “Excess Cash”) as set out in more detail below and in accordance with the provisions of the transaction agreement entered into between Mural, Sub and XOMA Royalty in respect of the Acquisition (the “Transaction Agreement”), as appended at Appendix IV of this Announcement.

The Base Price Per Share has been calculated on the basis of Mural having approximately $36.2 million in Closing Net Cash on the Closing Net Cash Date (the “Estimated Closing Net Cash”), and would be payable to Mural Shareholders on closing of the Acquisition regardless of the actual quantum of Mural’s Closing Net Cash on the Closing Net Cash Date. The Additional Price Per Share is intended to return any Excess Cash to Mural Shareholders. As a result, the Additional Price Per Share would only be payable to Mural Shareholders on closing of the Acquisition if Mural’s Closing Net Cash on the Closing Net Cash Date exceeds the Estimated Closing Net Cash. There is no certainty that Mural’s Closing Net Cash on the Closing Net Cash Date will exceed the Estimated Closing Net Cash and, if Mural’s Closing Net Cash does not the exceed Estimated Closing Net Cash, the amount of the Additional Price Per Share will be zero and each Mural Shareholder would receive only the Base Price Per Share.

The Additional Price Per Share is subject to a cap of a maximum amount of $0.205 per share.

The Acquisition, excluding any amount that may be payable in respect of the Additional Price Per Share, values the entire issued and to be issued share capital of Mural at approximately $36.2 million.

Excluding any Additional Price Per Share which may be payable as described above, the Acquisition represents a:

premium of approximately 13.1% to Mural’s closing share price of $1.80 on August 19, 2025, being the Business Day immediately before the date on which this Announcement has been released; and

premium of approximately 97.6% to Mural’s undisturbed closing share price of $1.03 on April 14, 2025 (being the last Business Day prior to the announcement of the commencement of the strategic review by the Mural Board on April 15, 2025).

Capitalised terms used in this Announcement and not otherwise defined have the meaning given to them in Appendix I.

Commenting on the Acquisition, Caroline Loew, Ph.D., Chief Executive Officer of Mural, said:

‘The Transaction Agreement with XOMA Royalty announced today is the result of a thorough and wide-ranging strategic review process, conducted with the support of our legal and financial advisors. We believe that this transaction, which is supported by our Board, achieves the goal of this strategic review process, which was to maximize shareholder value.’

Commenting on the Acquisition, Owen Hughes, Chief Executive Officer of XOMA Royalty, said:

‘XOMA Royalty looks forward to working with Mural to close the transaction as soon as possible.’

The Mural Directors, who hold Mural Shares representing, in aggregate, approximately 0.42% of Mural’s outstanding ordinary shares, Mural RSUs representing, in aggregate, approximately 1.27% of Mural’s outstanding ordinary shares and options to acquire Mural Shares representing, in aggregate, approximately 4.32% of Mural’s outstanding ordinary shares have entered into irrevocable undertakings to vote in favor of the Acquisition. All outstanding options to acquire Mural Shares held by the Mural Directors have a strike price above the maximum Consideration payable pursuant to the Acquisition and will be cancelled without the right to receive any Consideration in accordance with the terms of the Transaction Agreement.

Having taken into account the relevant factors, applicable risks and alternatives available to Mural, the Mural Board, which has been so advised by Lucid Capital Markets, LLC (“Lucid”), as financial adviser and Rule 3 adviser to Mural, as to the financial terms of the Acquisition, considers the terms of the Acquisition as set out in this Announcement to be fair and reasonable. Accordingly, the Mural Board intends to recommend that Mural Shareholders vote in favor of the Acquisition.

It is intended that the Acquisition will be implemented by means of a High Court sanctioned scheme of arrangement under Chapter 1 of Part 9 of the Irish Companies Act (or, if Sub elects, subject to the terms of the Transaction Agreement, compliance with the Irish Takeover Rules and with the consent of the Irish Takeover Panel, a Takeover Offer). The Acquisition is expected to close by the end of 2025, subject to the satisfaction of the Conditions, which include (i) the approval by Mural Shareholders of the Scheme Meeting Resolution and the Required EGM Resolutions; and (ii) the sanction of the Scheme by the High Court.

The Scheme Document, which will contain, among other things, further information about the Acquisition, notices convening the Scheme Meeting and the Extraordinary General Meeting (the “EGM”), the expected timetable for completion of the Acquisition and action to be taken by Mural Shareholders, will be published as soon as practicable following this Announcement. The Scheme Document will be included within the Proxy Statement to be filed by Mural with the U.S. Securities and Exchange Commission (the “SEC”) and sent to Mural shareholders as of the record date(s) to be established for voting at the Scheme Meeting and EGM in respect of the Acquisition.

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION IN WHOLE OR IN PART IN, DIRECTLY OR INDIRECTLY, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OR REGULATIONS OF THAT JURISDICTION

THIS ANNOUNCEMENT IS BEING MADE PURSUANT TO RULE 2.7 OF THE IRISH TAKEOVER RULES

About XOMA Royalty and Sub

XOMA Royalty Corporation is a biotechnology royalty aggregator playing a distinctive role in helping biotech companies achieve their goal of improving human health. XOMA Royalty acquires the potential future economics associated with pre-commercial and commercial therapeutic candidates that have been licensed to pharmaceutical or biotechnology companies. When XOMA Royalty acquires the future economics, the seller receives non-dilutive, non-recourse funding they can use to advance their internal drug candidate(s) or for general corporate purposes. XOMA Royalty has an extensive and growing portfolio of assets (asset defined as the right to receive potential future economics associated with the advancement of an underlying therapeutic candidate).

XOMA Royalty has its corporate headquarters in Emeryville, California. For more information, visit XOMA Royalty’s website at www.xoma.com.

XRA 5 Corp. is a Delaware corporation established for the sole purpose of implementing the Acquisition. As of the date of this Announcement, the entire issued and outstanding shares of capital stock of Sub are directly owned by XOMA Royalty.

Mural Oncology plc is a biotechnology company focused on using its protein engineering platform to develop cytokine-based immunotherapies for the treatment of cancer with the goal of delivering meaningful and clinical benefits to people living with cancer.

On March 25, 2025, Mural announced that, based on the interim analysis of results, its Phase 3 ARTISTRY-7 trial of nemvaleukin alfa (“nemvaleukin”) in combination with pembrolizumab did not achieve its primary endpoint of a statistically significant improvement in overall survival versus investigator’s choice chemotherapy. Mural also announced that ARTISTRY-7 would not continue to final analysis and Mural would cease development of nemvaleukin for platinum resistant ovarian cancer. On April 15, 2025, Mural announced that following review of data from its Phase 2 ARTISTRY-6 trial of nemvaleukin in mucosal and cutaneous melanoma and the previously announced results from the ARTISTRY-7 trial, Mural was discontinuing all clinical development of nemvaleukin and planned to immediately commence an exploration of strategic alternatives focused on maximizing shareholder value.

Mural has its registered office in Dublin, Ireland, and its primary facilities in Waltham, Mass. For more information, visit Mural’s website at www.muraloncology.com.

This summary should be read in conjunction with, and is subject to, the full text of the following Announcement and its appendices.

The Conditions to the Acquisition are set out in Appendix I of this Announcement and the Acquisition is subject to further terms to be set out in the Scheme Document. Certain terms used in this Announcement are defined in Appendix II of this Announcement. Appendix III of this Announcement contains certain sources of information and bases of calculation contained in this Announcement. Appendix IV of this Announcement contains a copy of the Transaction Agreement.

Lucid Capital Markets, LLC (Financial Adviser to Mural)

570 Lexington Ave, 40th Floor

Statements required by the Irish Takeover Rules

The Sub board of directors and XOMA Royalty’s board of directors accept responsibility for the information contained in this Announcement other than that relating to Mural, the Mural Group and the Mural Directors and members of their immediate families, related trusts and persons connected with them. To the best of the knowledge and belief of the Sub board of directors and XOMA Royalty board of directors (who, in each case, have taken all reasonable care to ensure that this is the case), the information contained in this Announcement for which they accept responsibility is in accordance with the facts and does not omit anything likely to affect the import of such information.

The Mural Directors accept responsibility for the information contained in this Announcement relating to Mural, the Mural Group and the Mural Directors and members of their immediate families, related trusts and persons connected with them. To the best of the knowledge and belief of the Mural Directors (who, in each case, have taken all reasonable care to ensure such is the case), the information contained in this Announcement for which they accept responsibility is in accordance with the facts and does not omit anything likely to affect the import of such information.

Lucid, which is authorized and regulated by the SEC and the Financial Industry Regulatory Authority (“FINRA”) in the United States, is acting as financial adviser exclusively for Mural and for no one else in connection with the subject matter of this Announcement and will not regard any other person as its client in relation to the matters in this Announcement and will not be responsible to anyone other than Mural for providing the protections afforded to clients of Lucid or its affiliates, nor for providing advice in relation to any matter referred to in this Announcement. Neither Lucid nor any of its subsidiaries, affiliates or branches owes or accepts any duty, liability or responsibility whatsoever (whether direct, indirect, consequential, whether in contract, in tort, under statute or otherwise) to any person who is not a client of Lucid in relation to the matters in this Announcement, any statement or other matter or arrangement referred to herein or otherwise.

Davy Corporate Finance, which is authorized and regulated in Ireland by the Central Bank of Ireland, is acting exclusively for XOMA Royalty and no one else in connection with the matters referred to in this Announcement and will not be responsible to anyone other than XOMA Royalty for providing the protections afforded to clients of Davy Corporate Finance or for providing advice in connection with the matters referred to in this Announcement.

Wilmer Cutler Pickering Hale and Dorr LLP and Arthur Cox LLP are acting as legal advisers on U.S. and Irish law matters respectively to Mural, and Gibson, Dunn & Crutcher LLP and Mason Hayes & Curran LLP are acting as legal advisers on U.S. and Irish law matters respectively to XOMA Royalty and Sub.

No Offer or Solicitation

This Announcement is for information purposes only and is not intended to, and does not, constitute or form part of any recommendation or offer, invitation or the solicitation of an offer to purchase, otherwise acquire, subscribe for, sell or otherwise dispose of, any securities or the solicitation of any proxy, vote or approval in any jurisdiction, whether pursuant to this Announcement or otherwise. The distribution of this Announcement in jurisdictions outside Ireland or the United States may be restricted by law and therefore persons into whose possession this Announcement comes should inform themselves about, and observe, such restrictions. Any failure to comply with the restrictions may constitute a violation of the securities law of any such jurisdiction.

The Acquisition will be made solely by means of the Scheme Document (or, if applicable, the Takeover Offer Documents), which will contain the full terms and conditions of the Acquisition, including details of how Mural Shareholders may vote in respect of the Acquisition. Any decision in respect of, or other response to, the Acquisition, should be made only on the basis of the information contained in the Scheme Document (or, if applicable, the Takeover Offer Documents).

This Announcement does not constitute a prospectus or a prospectus equivalent document.

Important Additional Information will be Filed with the SEC

In connection with the Acquisition, Mural intends to file with the SEC a Proxy Statement relating to the Scheme Meeting and the EGM (which will include the Scheme Document). The definitive Proxy Statement will be sent to Mural Shareholders as of the record date(s) to be established for voting at the Scheme Meeting and EGM. This Announcement is not a substitute for the Proxy Statement or any other document that Mural may file with the SEC or send to its shareholders in connection with the Acquisition. BEFORE MAKING ANY VOTING DECISION, HOLDERS OF MURAL SHARES ARE URGED TO READ THE PROXY STATEMENT (INCLUDING THE SCHEME DOCUMENT) ANY AMENDMENTS OR SUPPLEMENTS THERETO AND OTHER RELEVANT DOCUMENTS FILED OR TO BE FILED WITH THE SEC IN CONNECTION WITH THE ACQUISITION, INCLUDING ANY DOCUMENTS INCORPORATED BY REFERENCE THEREIN, CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE ACQUISITION, THE PARTIES TO THE SCHEME AND RELATED MATTERS.

Any vote in respect of the Scheme Meeting Resolution or the EGM Resolutions to approve the Acquisition, the Scheme or related matters, or other responses in relation to the Acquisition, should be made only on the basis of the information contained in the Proxy Statement (including the Scheme Document).

The Proxy Statement, if and when filed, as well as Mural’s other public filings with the SEC, may be obtained without charge at the SEC’s website at www.sec.gov and at Mural’s website https://ir.muraloncology.com/.

Mural Shareholders will also be able to obtain, without charge, a copy of the Proxy Statement (including the Scheme Document) and other relevant documents (when available) by directing a written request to Mural, Attn: Chief Legal Officer, Mural Oncology plc, Ten Earlsfort Terrace, D02 T380, Dublin 2, Ireland or by phone to 00 353 920 1000 or by contacting Investor Relations, via email at ir@muraloncology.com.

Participants in the Solicitation

Mural and certain of its directors, executive officers and employees may be deemed to be participants in the solicitation of proxies from Mural Shareholders in connection with the Acquisition and any other matters to be voted on at the Scheme Meeting or the EGM. Information about the directors and executive officers of Mural, including a description of their direct or indirect interests, by security holdings or otherwise, is set forth in Mural’s definitive proxy statement on Schedule 14A for its 2025 annual general meeting of shareholders, dated and filed with the SEC on April 28, 2025. Other information regarding the persons who may, under the rules of the SEC, be deemed to be participants in the solicitation of Mural Shareholders, including a description of their direct or indirect interests, by security holdings or otherwise, will be set forth in the Proxy Statement (which will contain the Scheme Document) related to the Acquisition and other relevant materials to be filed with the SEC in connection with the Acquisition. You may obtain free copies of these documents using the sources indicated above.

Cautionary Note Regarding Forward-Looking Statements

Statements contained in this Announcement regarding matters that are not historical facts are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 with respect to Mural, XOMA Royalty or Sub. Forward-looking statements are intended to be identified by words such as “anticipate”, “target”, “expect”, “estimate”, “intend”, “plan”, “believe”, “will”, “may”, “would”, “could” or “should” or other words of similar meaning or the negative thereof. Forward-looking statements include but are not limited to statements regarding Mural, XOMA Royalty and Sub’s intention to consummate the Acquisition, the approval of the Acquisition by Mural Shareholders, the payment of any Additional Price Per Share to Mural Shareholders, and the expected timing of the closing of the Acquisition.

These forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the actual results to be materially different from those expressed or implied by such forward-looking statements. Risks and uncertainties that may cause actual results to differ from expectations include: uncertainties as to the timing and completion of the Scheme Meeting and EGM; uncertainties as to the approval by Mural Shareholders of the Scheme Meeting Resolution or the Required EGM Resolutions; the possibility that closing conditions for the Acquisition may not be satisfied or waived, including the failure to receive sanction of the Scheme by the High Court; risks that ongoing costs to Mural will result in Mural’s Closing Net Cash on the Closing Net Cash Date not exceeding the Estimated Closing Net Cash, which will mean that no Additional Price Per Share is paid to Mural Shareholders; the other risks and uncertainties pertaining to Mural’s business, including those described in Mural’s most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q filed with the SEC, as well as Mural’s subsequent filings with the SEC, including the Proxy Statement; and the other risks and uncertainties pertaining to XOMA Royalty’s business, including those described in more detail in XOMA Royalty’s most recent filing on Form 10-Q and other filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. All subsequent oral or written forward-looking statements attributable to Mural, XOMA Royalty or Sub or any persons acting on their behalf are expressly qualified in their entirety by the cautionary statement above.

None of Mural, XOMA Royalty or Sub undertake any obligation to update or revise the forward-looking statements contained in this Announcement, whether as a result of new information, future events or otherwise, except to the extent legally required.

Disclosure Requirements of the Irish Takeover Rules

Under Rule 8.3(b) of the Irish Takeover Rules, any person who is, or becomes, “interested” (directly or indirectly) in 1% or more of any class of “relevant securities” of Mural must disclose all “dealings” in such “relevant securities” during the “offer period”. The disclosure of a “dealing” in “relevant securities” by a person to whom Rule 8.3(b) applies must be made by no later than 3:30 pm (U.S. Eastern Time) on the “business day” following the date of the relevant “dealing”. A dealing disclosure must contain the details specified in Rule 8.6(b) of the Irish Takeover Rules, including details of the dealing concerned and of the person’s interests and short positions in any “relevant securities” of Mural.

All “dealings” in “relevant securities” of Mural by a bidder, or by any party Acting in Concert with a bidder, must also be disclosed by no later than 12:00 noon (U.S. Eastern Time) on the “business day” following the date of the relevant “dealing”.

If two or more persons co-operate on the basis of an agreement, either express or tacit, either oral or written, to acquire an “interest” in “relevant securities” of Mural, they will be deemed to be a single person for the purpose of Rule 8.3(a) and (b) of the Irish Takeover Rules.

A disclosure table, giving details of the companies in whose “relevant securities” dealing disclosures should be made, can be found on the Irish Takeover Panel’s website at www.irishtakeoverpanel.ie.

“Interests in securities” arise, in summary, when a person has long economic exposure, whether conditional or absolute, to changes in the price of securities. In particular, a person will be treated as having an “interest” by virtue of the ownership or control of securities, or by virtue of any option in respect of, or derivative referenced to, securities.

Terms in quotation marks in this section are defined in the Irish Takeover Rules, which can also be found on the Irish Takeover Panel’s website.

If you are in any doubt as to whether or not you are required to disclose a “dealing” under Rule 8, please consult the Irish Takeover Panel’s website at www.irishtakeoverpanel.ie or contact the Irish Takeover Panel on telephone number +353 1 678 9020.

No Profit Forecast or Merger Benefit Statement

No statement in this Announcement is intended to constitute a profit forecast or profit estimate for any period, nor should any statement be interpreted to mean that earnings or earnings per share of Mural will, for the current or future financial years or other periods, necessarily match or be greater or lesser than those for the relevant preceding financial periods. No statement in this Announcement constitutes an asset valuation or a quantified financial benefits statement within the meaning of the Irish Takeover Rules.

Right to Switch to a Takeover Offer

XOMA Royalty reserves the right to elect, subject to the terms of the Transaction Agreement, compliance with the Irish Takeover Rules and with the consent of the Irish Takeover Panel, to implement the Acquisition by way of a Takeover Offer for the entire issued and to be issued share capital of Mural (other than any Mural Shares beneficially owned by XOMA Royalty or its subsidiaries (if any)) as an alternative to the Scheme. In such an event, the Takeover Offer will be implemented on the same terms (subject to appropriate amendments, including without limitation an acceptance condition set at 80% of the shares to which such offer relates), so far as applicable, as those which would apply to the Scheme.

If XOMA Royalty exercises its right to implement the Acquisition by way of a Takeover Offer as an alternative to the Scheme, subject to the provisions of the Transaction Agreement and with the Irish Takeover Panel’s consent, such Takeover Offer would be made in compliance with applicable U.S. Law and regulations, including the tender offer rules under the Exchange Act. If a Takeover Offer is commenced, additional information regarding such Takeover Offer will be provided to Mural Shareholders at that time.

Publication on Website

In accordance with Rule 26.1 of the Irish Takeover Rules, a copy of this Announcement will be available on XOMA Royalty’s website at https://www.investors.xoma.com and Mural’s website at https://ir.muraloncology.com/ by no later than 12:00 noon (U.S. Eastern Time) on the business day following publication of this Announcement. Neither the content of the websites referred to in this Announcement nor the content of any other websites accessible from hyperlinks on such websites is incorporated into, or forms part of, this Announcement.

Requesting Hard Copy Information

Any Mural Shareholder may request a copy of this Announcement and / or any information incorporated by reference into this Announcement in hard copy form by directing a written request to Mural, Attn: Chief Legal Officer, Mural Oncology plc, Ten Earlsfort Terrace, D02 T380, Dublin 2, Ireland or by phone to 00 353 920 1000 or by contacting Investor Relations, via email at ir@muraloncology.com.

Any written requests must include the identity of the Mural Shareholder and any hard copy documents will be posted to the address of the Mural Shareholder provided in the written request. If you have received this Announcement in electronic form, a hard copy of this Announcement and / or any document or information incorporated by reference into this Announcement will not be provided unless such a request is made.

Certain figures included in this Announcement have been subjected to rounding adjustments. Accordingly, figures shown for the same category presented in different tables may vary slightly and figures shown as totals in certain tables may not be an arithmetic aggregation of the figures that precede them.

Overseas Shareholders

The laws of certain jurisdictions may affect the availability of the Acquisition to persons who are not resident in Ireland or the United States. Persons who are not resident in Ireland or the United States, or who are subject to laws of any jurisdiction other than Ireland or the United States, should inform themselves about, and observe, any applicable legal or regulatory requirements. Any failure to comply with any applicable legal or regulatory requirements may constitute a violation of the laws and/or regulations of any such jurisdiction. To the fullest extent permitted by applicable law, Mural, XOMA Royalty and Sub disclaim any responsibility and liability for the violation of such restrictions by any person.

This Announcement has been prepared for the purpose of complying with the laws of Ireland and the Irish Takeover Rules and the information disclosed may not be the same as that which would have been disclosed if this Announcement had been prepared in accordance with the laws of jurisdictions outside of Ireland.

The Acquisition will not be made available, directly or indirectly, in any Restricted Jurisdiction, and the Acquisition will not be capable of acceptance from within a Restricted Jurisdiction. No person may vote in favor of the Acquisition by any use, means, instrumentality or facilities from within a Restricted Jurisdiction or any other jurisdiction if to do so would constitute a violation of the Laws of that jurisdiction.

The release, publication or distribution of this Announcement in or into certain jurisdictions may be restricted by the laws of those jurisdictions. Accordingly, copies of this Announcement and all other documents relating to the Acquisition are not being, and must not be, released, published, mailed or otherwise forwarded, distributed or sent in, into or from any Restricted Jurisdiction or any jurisdiction where to do so would violate the Laws of that jurisdiction. Persons receiving such documents (including, without limitation, nominees, trustees and custodians) should observe these restrictions. Failure to do so may constitute a violation of the securities laws of any such jurisdiction. If the Acquisition is implemented by way of a Takeover Offer (unless otherwise permitted by applicable Law or regulation), the Takeover Offer may not be made, directly or indirectly, in or into or by use of the mails or any other means or instrumentality or facilities (including, without limitation, facsimile, email or other electronic transmission, telex or telephone) of interstate or foreign commerce of, or any facility of a national, state or other securities exchange of any Restricted Jurisdiction and the Takeover Offer will not be capable of acceptance by any such use, means, instrumentality or facilities from within any Restricted Jurisdiction or any other jurisdiction if to do so would constitute a violation of the Laws of that jurisdiction.

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION IN WHOLE OR IN PART IN, DIRECTLY OR INDIRECTLY, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OR REGULATIONS OF THAT JURISDICTION

THIS ANNOUNCEMENT IS BEING MADE PURSUANT TO RULE 2.7 OF THE IRISH TAKEOVER RULES

Mural Oncology plc (Nasdaq: MURA) and XOMA Royalty Corporation (Nasdaq: XOMA) today announced they have entered into a definitive agreement pursuant to which Sub, a wholly-owned subsidiary of XOMA Royalty, has agreed to acquire the entire issued and to be issued share capital of Mural for between $2.035 and $2.24 in cash per share, subject to the satisfaction of the closing conditions set out in Appendix I of this Announcement. Following a strategic review process, the Mural Board determined the acquisition and cash offer by XOMA Royalty is in the best interests of all Mural Shareholders and have approved the Acquisition. The Acquisition has also been approved by the boards of directors of XOMA Royalty and Sub.

It is intended that the Acquisition will be implemented by means of a High Court sanctioned scheme of arrangement under Chapter 1 of Part 9 of the Irish Companies Act (or, if Sub elects, subject to the terms of the Transaction Agreement, compliance with the Irish Takeover Rules and with the consent of the Irish Takeover Panel) a Takeover Offer. The Acquisition is expected to close by the end of 2025, subject to the satisfaction of the Conditions, which include (i) the approval by Mural Shareholders of the Scheme Meeting Resolution and the Required EGM Resolutions; and (ii) the sanction of the Scheme by the High Court.

2. Transaction Details

Under the terms of the Acquisition and subject to certain conditions, at closing, each Mural Shareholder (i) would receive a base cash price of $2.035 per share (the “Base Price Per Share”), which has been calculated on the basis of Mural having approximately $36.2 million of Closing Net Cash on the Closing Net Cash Date (the “Estimated Closing Net Cash”), and (ii) may receive an additional cash amount of up to $0.205 per share (the “Additional Price Per Share”) which would be calculated on the basis of the amount by which Mural’s Closing Net Cash on the Closing Net Cash Date exceeds the Estimated Closing Net Cash as set out in more detail below and in accordance with the provisions of the transaction agreement entered into by and among Mural, Sub and XOMA Royalty in respect of the Acquisition (the “Transaction Agreement”), as appended at Appendix IV of this Announcement.

The Acquisition, excluding any amount that may be payable in respect of the Additional Price Per Share, values the entire issued and to be issued share capital of Mural at approximately $36.2 million.

Excluding any Additional Price Per Share which may be payable (as described in more detail below), the Acquisition represents a:

premium of approximately 13.1% to Mural’s closing share price of $1.80 on August 19, 2025, being the Business Day immediately before the date on which this Announcement has been released; and

premium of approximately 97.6% to Mural’s undisturbed closing share price of $1.03 on April 14, 2025 (being the last Business Day prior to the announcement of the commencement of the strategic review by the Mural Board on April 15, 2025).

The sources and bases of information contained in this Announcement to calculate the implied value of the Acquisition are set out in Appendix III.

Subject to satiscfaction of the Conditions, on closing of the Acquisition, Mural Shareholders would receive between $2.035 and $2.24 in cash per share, comprised of the Base Price Per Share of $2.035 and an Additional Price Per Share which may be payable of up to $0.205.

The Base Price Per Share has been determined by XOMA Royalty and Sub based on an estimated amount of Mural’s Closing Net Cash at the Closing Net Cash Date of approximately $36.2 million. Subject to satisfaction of the Conditions and closing of the Acquisition, Mural Shareholders would receive the Base Price Per Share regardless of whether the actual quantum of Mural’s Closing Net Cash on the Closing Net Cash Date exceeds, is equal to or is less than the Estimated Closing Net Cash.

The Additional Price Per Share would be calculated on the basis of the amount by which Mural’s Closing Net Cash as of the Closing Net Cash Date as determined between XOMA Royalty, Sub and Mural in accordance with the provisions of clause 2.4 of the Transaction Agreement exceeds the Estimated Closing Net Cash (the “Excess Cash”). The Additional Price Per Share is intended to return any Excess Cash to Mural Shareholders, subject to a cap of a maximum amount of $0.205 per share. As a result, the Additional Price Per Share will only be payable to Mural Shareholders on closing of the Acquisition if Mural’s Closing Net Cash on the Closing Net Cash Date exceeds the Estimated Closing Net Cash.

There is no certainty that Mural’s Closing Net Cash on the Closing Net Cash Date will exceed the Estimated Closing Net Cash and, if Mural’s Closing Net Cash on the Closing Net Cash Date does not exceed its Estimated Closing Net Cash, the amount of the Additional Price Per Share will be zero and each Mural Shareholder would receive only the Base Price Per Share.

Closing Net Cash, for this purpose, means, without duplication, (i) the sum of Mural’s cash and cash equivalents and marketable securities as of the Closing Net Cash Date, determined in accordance with U.S. GAAP, applied on a basis consistent with Mural’s application thereof in Mural’s consolidated financial statements plus (ii) the prepaid expenses, receivables and deposits of Mural set forth on Schedule 4 of the Transaction Agreement, minus (iii) the sum of Mural’s consolidated short-term and long-term contractual obligations and monetary liabilities (including Indebtedness) accrued or incurred by Mural as of the Closing Net Cash Date, minus (iv) the Transaction Expenses, minus (v) the Estimated Post-Closing Costs, minus (vi) $5.5 million, each in a manner consistent with Appendix 1 to the Mural Disclosure Schedule.

Closing Net Cash Date means immediately prior to the Effective Time on the Effective Date.

It is expected that confirmation of the Additional Price Per Share will be communicated to Mural Shareholders by separate announcement prior to the date of the Court Hearing.

The Additional Price Per Share calculated in accordance with the terms of the Transaction Agreement shall be rounded to four decimal places.

4. Background to and Reasons for the Acquisition

4.1. Background to the Strategic Review

Mural is a biotechnology company focused on using its protein engineering platform to develop cytokine-based immunotherapies for the treatment of cancer with the goal of delivering meaningful and clinical benefits to people living with cancer.

On March 25, 2025 Mural announced that, based on the interim analysis of results, its Phase 3 ARTISTRY-7 trial of nemvaleukin alfa (“nemvaleukin”) in combination with pembrolizumab did not achieve its primary endpoint of a statistically significant improvement in overall survival versus investigator’s choice chemotherapy. Mural also announced that ARTISTRY-7 would not continue to final analysis and Mural would cease development of nemvaleukin for platinum resistant ovarian cancer. On April 15, 2025, Mural announced that following review of data from its Phase 2 ARTISTRY-6 trial of nemvaleukin in mucosal and cutaneous melanoma and the previously announced results from the ARTISTRY-7 trial, it was discontinuing all clinical development of nemvaleukin and planned to immediately commence an exploration of strategic alternative focused on maximizing shareholder value (the “Strategic Review”).