Amendment: SEC Form SCHEDULE 13D/A filed by iTeos Therapeutics Inc.

Item 4 of the Schedule 13D is amended by adding the following: Merger Agreement and Related Transactions: On July 18, 2025, the Issuer entered into an Agreement and Plan of Merger (the "Merger Agreement") with Concentra and Concentra Merger Sub VIII, Inc., a Delaware corporation and a wholly owned subsidiary of Concentra ("Merger Sub"). The Merger Agreement provides for, among other things: (i) the acquisition of all of the Issuer's outstanding shares of common stock, par value $0.001 per share (the "Common Stock"), by Concentra through a tender offer (the "Offer"), for a price per share of the Common Stock of (A) $10.047 in cash, subject to applicable tax withholding and without interest, plus (B) one contingent value right (a "CVR") and (ii) the merger of Merger Sub with and into the Issuer (the "Merger") with the Issuer surviving the Merger. Closing of the Offer is subject to certain conditions, including that the number of shares of Common Stock validly tendered equals at least one share more than 50% of all shares of Common Stock then issued and outstanding as of the expiration of the Offer, the Closing Net Cash (as defined in the Merger Agreement) shall be no less than $475 million, and other customary conditions. The foregoing description of the Merger Agreement and related transactions does not purport to be complete and is qualified in its entirety by reference to the full text of the Merger Agreement, which is attached as Exhibit 2.1 to the Current Report on Form 8-K filed by the Issuer with the Securities and Exchange Commission on July 21, 2025. Guaranty: Concurrently with the execution of the Merger Agreement and the CVR Agreement (as defined below), and as a condition and inducement to the Issuer's willingness to enter into the Merger Agreement, Tang Capital Partners, LP, a Delaware limited partnership, has delivered to the Issuer a duly executed limited guaranty, dated as of the date of the Merger Agreement (the "Limited Guaranty"), in favor of the Issuer, in respect of certain of Concentra's and Merger Sub's (including as the surviving corporation of the Merger) obligations arising under, or in connection with, the Merger Agreement and CVR Agreement. Certain obligations under the Limited Guaranty are subject to: (i) a cap of $465.0 million, which includes certain enforcement costs, under the Merger Agreement; and (ii) a cap of an amount equivalent to the CVR Proceeds (as defined in the CVR Agreement), plus certain enforcement costs up to the CVR Expense Cap (as defined below), under the CVR Agreement. Contingent Value Rights Agreement: At or prior to the time at which Concentra first irrevocably accepts for purchase the shares of Common Stock tendered in the Offer, Concentra and Merger Sub expect to enter into a Contingent Value Rights Agreement (the "CVR Agreement") with a rights agent ("Rights Agent") and a representative, agent and attorney-in-fact of the holders of CVRs. Each CVR will represent a contractual right to receive contingent cash payments equal to: (i) 100% of the amount by which Closing Net Cash (as finally determined pursuant to the Merger Agreement) exceeds $475 million, adjusted downward for any claims or downward or upward, as applicable, for any changes in amounts accrued in the Closing Net Cash that, in each case, are not accounted for in such Closing Net Cash; and (ii) 80% of the Net Proceeds (as defined in the CVR Agreement), if any, from any sale, transfer, license or other disposition (each, a "Disposition") by Concentra or any of its affiliates, including the Issuer after the Merger, of all or any part of the Issuer's and its subsidiaries' (a) product candidates known as (i) EOS-984, a small molecule in oncology inhibiting ENT1; and (ii) EOS-215, an anti-TREM2 (anti-Triggering Receptor Expressed on Myeloid Cells 2) antibody, including, in each case, any form or formulation, and any improvement or enhancement, of any such product candidate; (b) preclinical obesity program targeting ENT1, including EOS-518 and EOS-855, and any product candidate contained in or arising from, such program; (c) program developing a small molecule inhibiting PTPNI1/2, and any product candidate contained in or arising from, such program; and (d) any product or product candidate covered by the claims of a patent, patent application, provisional patent application or similar instrument owned by the Issuer or a subsidiary of the Issuer as of the Merger Closing Date (the "CVR Products") that occurs within the period beginning on the Merger Closing Date and ending on the six (6) month anniversary following the Merger Closing Date (the "Disposition Period"), provided the proceeds from such Disposition are paid to or received by Concentra or any of its affiliates prior to the eight (8) year anniversary following the end of the Disposition Period. In the event that no Dispositions occur by the six (6) month anniversary of the Merger Closing Date, holders of the CVRs will not receive any payment pursuant to the CVR Agreement with respect to a Disposition. Concentra shall, and shall cause the Issuer after the Merger to, use commercially reasonable efforts to spend up to $350,000 (the "CVR Expense Cap") to, among other things, during the Disposition Period: (i) enter into one or more Disposition Agreements (as defined in the CVR Agreement) as soon as practicable following the Effective Time; (ii) retain an employee or consultant of Concentra or Merger Sub for the purpose of maintaining and preserving the CVR Products and seeking, negotiating and executing Disposition Agreements; (iii) maintain the CVRs (including fees and expenses related to the Rights Agent and the Representative (as defined in the CVR Agreement)); (iv) maintain and prosecute the intellectual property relating to the CVR Products set forth on Schedule 1 to the CVR Agreement; and (v) continue the CMC Activities (as defined in the Merger Agreement) of the CVR Products to the extent the costs associated with such CMC Activities were included in the Closing Net Cash Schedule. The foregoing description of the CVR Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the CVR Agreement, which is attached as Exhibit 10.1 to the July 21, 2025 Form 8-K.

Exhibit 1: Joint Filing Agreement by and among the Reporting Persons (filed as Exhibit 1 of the 13D filed on June 12, 2025 by the Reporting Persons with respect to the Common Stock of the Issuer). Exhibit 2: Schedule A: Transactions during the past 60 days (filed as Exhibit 2 of the 13D filed on June 12, 2025 by the Reporting Persons with respect to the Common Stock of the Issuer). Exhibit 3: Agreement and Plan of Merger, dated as of July 18, 2025, by and among iTeos Therapeutics, Inc., Concentra Biosciences, LLC, and Concentra Merger Sub VIII, Inc. (filed as Exhibit 2.1 of the Issuer's Current Report filed on Form 8-K on July 21, 2025).