Summary of Significant Transactions

Acquisition of Ouro Medicines and collaboration with Gilead Sciences, Inc. (“Gilead”)

Framework Agreement with Gilead

On March 23, 2026, Gilead announced that it had entered into a definitive agreement to acquire all of the outstanding equity interests of Ouro Medicines Inc. (“Ouro” or “Ouro Medicines”) for a total upfront cash consideration of $1.675 billion, subject to customary adjustments, and up to $500 million in contingent milestone payments (the “Acquisition”). In connection with the Acquisition, we have entered into a Framework Agreement with Gilead, which comprises the following components:

1. relief under the Option, License and Collaboration Agreement dated July 14, 2019 between Gilead and us (the “OLCA”), to enable us to deploy at least $500 million of our available cash independently from Gilead and outside the scope of the OLCA and the Ouro transaction, including up to $150 million for share buybacks (the “OLCA Waiver”) – for more information on the OLCA please refer to the Annual Report 2025;

2. a binding term sheet granting us licenses to certain intellectual property rights relating to Ouro’s research programs, including Ouro’s lead program of gamgertamig for development purposes, and to the BCMAxCD19xCD3 T cell engager program and other preclinical programs for development and commercialization purposes (the “Licensing Term Sheet”); and

3. a binding term sheet pursuant to which we would acquire substantially all Ouro’s operational assets in connection with the Acquisition, including facilities and personnel, such that we would obtain an operating business (the “Asset Acquisition Term Sheet”).

The acquisition by Gilead was completed on June 3, 2026 and the Framework Agreement came into effect at the same date, followed by the aquisition by us on June 4, 2026.

Financial details of the Framework Agreement

Under the Framework Agreement, our share of the total consideration for the Acquisition amounts to 50% of the upfront consideration of $1.675 billion and 50% of any contingent milestone payments, which also includes the consideration under the Asset Acquisition Term Sheet.

Under the Licensing Term Sheet, we are required to fund our share of payments owed to Keymed Biosciences Chengdu Co., Ltd (“Keymed”) under the head license agreement between Keymed and Ouro (the “Keymed Agreement”), comprising 25% of the milestone payments and 50% of the royalty payments that become due to Keymed with respect to gamgertamig products. Based on Ouro’s original transaction with Keymed, Keymed owns the right to develop the program in Greater China and is entitled to total development and commercial milestones of up to $610 million and tiered royalties of 7% – 14% on net sales of gamgertamig.

We will also bear all costs of development prior to registrational studies for gamgertamig pursuant to agreed-upon research plans and budgets, including Ouro’s current clinical trials, while costs of registration-enabling clinical development would be shared equally between the parties, with execution leadership divided by indication.

We are eligible for up to $100 million in milestone payments upon Gilead’s initiation of the first registrational trials for gamgertamig in certain other indications.

Gilead will be responsible for commercialization, including all related costs, globally outside of Keymed’s territories. Upon commercialization, Gilead will pay us tiered royalties between 20 – 23% on net sales of gamgertamig.

In addition, we in-licensed a preclinical portfolio of three additional autoimmune focused programs originally from Ouro, on which Gilead has the option to opt into a 50/50 profit split post clinical proof-of-concept for $75 million per program.

The OLCA Waiver allows us to spend $500 million of cash (and any additional cash generated from that amount) to acquire or develop research programs independently from Gilead and not subject to Gilead’s rights under the OLCA. In addition, we can elect to use up to $150 million of that $500 million for potential share repurchases, dividend payments and other distributions of our capital stock, subject to certain limitations.

Acquisition of Ouro Medicines Inc.

On June 4, 2026, through our acquisition of 100% of the shares of Ouro Medicines Inc. renamed as Lakefront Biotherapeutics West LLC, we have acquired substantially all of Ouro Medicines’ team including 25 FTEs and operational assets in connection with Gilead’s acquisition of Ouro Medicines and will collaborate with Gilead on the development of gamgertamig (an investigational BCMAxCD3 bispecific T-cell engager for the treatment of autoantibodies driven immune-mediated disease).

The main reason for this acquisition is to invest in differentiated science and accelerate the development of therapies that address significant unmet need. Combined with existing expertise in immunology and cell therapy, this approach supports our ambition to shift treatment paradigms from chronic disease management toward the potential for durable immune reset.

The acquisition of Ouro Medicines Inc. (now renamed Lakefront Biotherapeutics West LLC) is further described in the notes to our interim consolidated financial statements.

Conversion of convertible loan to Coultreon Biopharma BV into shares

In April 2025, we participated in Onco3R’s start-up capital via a convertible loan facility of €20 million, which would convert during the next equity financing round. Onco3R Therapeutics BV was renamed to Coultreon Biopharma BV (“Coultreon”). This convertible loan facility was presented in the line “Convertible loan” in our statement of financial position and was measured at fair value through profit or loss.

In April 2026, Coultreon announced the closing of an oversubscribed $125 million Series A financing round. The financing will support the clinical development of Coultreon’s lead immunology program, COL-5671 (formerly O3R-5671), a highly selective SIK3 inhibitor in Phase 1, with potential to demonstrate clinical proof-of-concept in 2027. COL-5671 was initially developed by Lakefront and ownership was fully transferred to Coultreon in April 2025, when Lakefront provided seed financing to the company with a convertible note investment that converted into equity ownership in Coultreon in connection with Series A financing. As of June 30, 2026, Lakefront holds 29.12% of Coultreon’s currently issued and outstanding shares.

Share Repurchase Program

At the Extraordinary Shareholder Meeting held on April 28, 2026 (the “2026 EGM”), it was resolved to authorize the Board of Directors, without prior authorization of the Shareholders’ Meeting, in accordance with Belgian law and within the limits provided, to acquire a maximum of ten per cent (10%) of the number of shares existing at the end of the 2026 EGM, for a consideration equivalent to the closing price of Lakefront’s share on Euronext Brussels, on the day immediately preceding the acquisition, plus a maximum of fifteen percent (15%) or minus a maximum of fifteen percent (15%). This authorization is valid for five years from the date of the publication in the Annexes to the Belgian State Gazette of the minutes of the 2026 EGM.

On June 9, 2026, we announced the launch of a share repurchase program (the “Program”), under which we may repurchase ordinary shares for an aggregate amount of up to €50 million. Repurchases under the Program may be made no later than December 31, 2026. The Program is entered into via a discretionary mandate with Morgan Stanley & Co International PLC.

As of June 30, 2026, we were holding 241,904 of our own ordinary shares, for a total purchase value of €6,078,112.05 at an average price of €25.13 per share (of which €2,869,971.03 was paid in cash and €3,208,141.02 still to be paid on June 30, 2026). The outstanding amount (unpaid) represents a financial liability that was presented as part of the trade and other liabilities line in our consolidated statement of financial position. The purchase value is disclosed on the line “Own shares” in our consolidated statement of changes in equity.