Company: DAWN
Filing Date: 2025-11-13
Form Type: SC TO-C
Source: 0001104659-25-110815
Chunk: 7

Company: Day One Biopharmaceuticals, Inc.
Filing Date: 2025-11-13
Form: SC TO-C
Chunk 7
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 of the form of Tender and Support Agreement,
which is attached as Exhibit 10.1 hereto and is incorporated by reference herein.

Contingent Value Rights Agreement

At or prior to the time at which Merger Sub irrevocably accepts for
purchase all Target Shares validly tendered (and not validly withdrawn) pursuant to the Offer, Parent and the Rights Agent will enter
into the CVR Agreement. The CVRs are contractual rights only and not transferable except under certain limited circumstances, will not
be certificated or evidenced by any instrument and will not be registered with the SEC or listed for trading. The CVRs will not have any
voting or dividend rights and will not represent any equity or ownership interest in Parent, Merger Sub or Target or any of their affiliates.

Each CVR represents a right to receive the following cash payments,
without interest and subject to reduction for any applicable tax withholding (the “Milestone Payments”) if the following milestones
(the “Milestones”) are achieved:

| · | $1.00 per CVR, payable upon the U.S. Food and Drug Administration (the “FDA”) granting “breakthrough therapy”  
 designation in the United States for emiltatug ledadotin (XMT-1660) (“Emi-Le”) on or before December 31, 2027; |

| · | $1.25 per CVR, payable upon receipt by Parent or any of its affiliates (including the surviving corporation) of the $8.0 million milestone    
 payment payable upon achievement of a specified development milestone set forth in that certain Research Collaboration and License Agreement, 
 dated as of February 2, 2022, by and between the Target and Janssen Biotech, Inc., on or before December 31, 2026;                            |

| · | $4.00 per CVR, payable upon occurrence of the first dosing of the first participant in a Registrational Clinical Trial (as defined 
 in the CVR Agreement) of Emi-Le for adenoid cystic carcinoma type 1 (“ACC-1”) on or before December 31, 2027;                      |

| · | $9.00 per CVR, payable upon the occurrence of Regulatory Approval (as defined in the CVR Agreement) by the FDA for Emi-Le indicated 
 for use in ACC-1 on or before December 31, 2030;                                                                                    |

| · | $2.00 per CVR, payable