Form 8-K

8-K — Rallybio Corp

Accession: 0001193125-26-202601

Filed: 2026-05-04

Period: 2026-05-03

CIK: 0001739410

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Termination of a Material Definitive Agreement

Item: Financial Statements and Exhibits

Documents

8-K — d19625d8k.htm (Primary)

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8-K

8-K (Primary)

Filename: d19625d8k.htm · Sequence: 1

8-K

Rallybio Corp NASDAQ false 0001739410 0001739410 2026-05-03 2026-05-03

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(D)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): May 3, 2026

RALLYBIO CORPORATION

(Exact name of Registrant as Specified in its Charter)

Delaware

001-40693

85-1083789

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

234 Church Street

New Haven, Connecticut 06410

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (203) 859-3820

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading

Symbol(s)

Name of each exchange

on which registered

Common Stock, par value $0.0001 per share

RLYB

NASDAQ Capital Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.02.

Termination of a Material Definitive Agreement.

As previously disclosed, on March 1, 2026, Rallybio Corporation (“Rallybio”) entered into an Agreement and Plan of Merger and Reorganization (the “Merger Agreement”) with Candid Therapeutics, Inc. (“Candid”), and Farmington Merger Sub, Inc., a wholly-owned subsidiary of Rallybio (“Merger Sub”). For a description of the Merger Agreement, please refer to Item 1.01 of Rallybio’s Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on March 2, 2026 (the “March 2026 8-K”), which description is incorporated herein by reference. Such description is qualified in its entirety by reference to the full text of the Merger Agreement, which is attached as Exhibit 2.1 to the March 2026 8-K, which is incorporated herein by reference.

On May 3, 2026, Candid terminated the Merger Agreement concurrently with entering into a Permitted Alternative Agreement (as defined in the Merger Agreement) with UCB S.A. (“UCB”). As a result of the termination of the Merger Agreement, Rallybio is entitled to receive a $50,000,000 Parent Termination Fee (as defined in the Merger Agreement). In connection with such termination, on May 1, 2026, Rallybio, Candid and UCB entered into a waiver to the Merger Agreement (the “Waiver”), pursuant to which (a) Rallybio (i) waived certain of its rights under the Merger Agreement and the Company Stockholder Support Agreement (as defined in the Merger Agreement) related to the Company Determination Notice and Company Notice Period; (ii) agreed that the payment by Candid of the Parent Termination Fee and the reimbursement of certain expenses could be paid on the first business day after the termination of the Merger Agreement; and (iii) subject to Rallybio receiving such fee and expense reimbursement, agreed to release all claims against Candid, UCB and their respective affiliates in respect of the Merger Agreement, the Contemplated Transactions (as defined in the Merger Agreement) or the termination of the Merger Agreement or the Company Stockholder Support Agreement, and (b) Candid and UCB, on behalf of themselves and their respective affiliates, agreed to release Parent and its affiliates from all claims in respect of the Merger Agreement, the Contemplated Transactions or the termination of the Merger Agreement or the Parent Stockholder Support Agreement (as defined in the Merger Agreement). Rallybio intends to withdraw its registration statement on Form S-4 initially filed with the SEC on March 17, 2026 and amended on April 24, 2026.

The summary of the Waiver set forth under this Item 1.02 is qualified in its entirety by reference to the complete terms and conditions of the Waiver, which is filed as Exhibit 2.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Item 9.01.

Financial Statements and Exhibits.

(d)

Exhibits.

Exhibit

Number

Exhibit Description

2.1

Waiver, dated as of May 1, 2026, by and among Rallybio Corporation, Candid Therapeutics, Inc. and UCB S.A.

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

RALLYBIO CORPORATION

Date: May 4, 2026

By:

/s/ Jonathan I. Lieber

Name:

Jonathan I. Lieber

Title:

Chief Financial Officer and Treasurer

EX-2.1

Filename: d19625dex21.htm · Sequence: 2

EX-2.1

Exhibit 2.1

Confidential

WAIVER

This Waiver (this

“Waiver”), dated as of May 1, 2026, to the Agreement (as defined below) is executed and delivered by Rallybio Corporation, a Delaware corporation (“Parent”), Candid Therapeutics, Inc., a

Delaware corporation (the “Company”) and UCB S.A. (“UCB”). Capitalized terms used but not otherwise defined in this Waiver shall have the same meanings ascribed to such terms in the Agreement (as

defined below).

WHEREAS, that certain Agreement and Plan of Merger and Reorganization (the “Agreement”), dated as of

March 1, 2026, was entered into by and among Parent, Farmington Merger Sub, Inc., a Delaware corporation and wholly-owned subsidiary of Parent, and the Company;

WHEREAS, the Company has notified Parent that it has received Acquisition Proposals from UCB (collectively, as may be modified, the “UCB

Proposals”); and

WHEREAS, the Company has requested that Parent waive (i) the Company Determination Notice, the Company Notice Period,

and the related rights set forth in Section 5.2(e)(i) of the Agreement with respect to each of the UCB Proposals; (ii) the requirement that the Parent Termination Fee be paid concurrently with the termination of the Merger Agreement as set

forth in Section 9.3(c)(ii); and (iii) the restrictions in Section 1.7 of the Company Stockholder Support Agreement.

NOW, THEREFORE,

pursuant to Section 10.3(b) of the Agreement, Parent hereby (a) waives, as applicable, the Company Determination Notice, the Company Notice Period, and all associated rights of Parent under Section 5.2(e) of the Agreement with respect

to each of the UCB Proposals and (b) agrees and acknowledges that the Company shall not be deemed to be in breach of Section 5.2(e) of the Agreement with respect to the UCB Proposals, including for purposes of exercising the

Company’s termination right pursuant to Section 9.1(h) of the Agreement.

NOW, THEREFORE, pursuant to Section 10.3(b) of the Agreement,

Parent hereby (a) waives the requirement under Section 9.3(c)(ii) of the Agreement that the Parent Termination Fee be paid concurrently with the termination of the Agreement in connection with the entry into any Permitted Alternative

Agreement entered into with UCB (but, for the avoidance of doubt, Parent does not waive the Company’s obligation to pay a Parent Termination Fee under Section 9.3(c)(ii) of the Agreement), and (b) agrees that the Company shall

deliver (x) the Parent Termination Fee of $50,000,000 plus (y) $375,000, which amount shall be deemed to satisfy the Company’s obligations to bear fees and expenses paid or to be paid to a financial printer or the SEC pursuant to

Section 9.3(a)(i) of the Agreement (the “Reimbursement”) by wire transfer of same-day funds in accordance with Section 9.3 of the Agreement as early as practicable on

May 4, 2026 and in no event later than the close of business on such date; provided that, if the Company terminates the Agreement on a Business Day, the Parent Termination Fee and the Reimbursement shall be delivered by wire transfer of same-day funds in accordance with Section 9.3 of the Agreement as early as practicable on the date of such termination.

NOW, THEREFORE, pursuant to Section 4.4 of the Company Stockholder Support Agreement, Parent hereby

(a) waives, as applicable, the provisions of Section 1.7 of the Company Stockholder Support Agreement, to the extent they may apply with respect to the UCB Proposals or any solicitation of votes, consents or approvals from any Company

Signatory in respect of the UCB Proposal or any Permitted Alternative Agreement entered into with UCB, and (b) agrees not to exercise any of its rights under Section 1.4 of the Company Stockholder Support Agreement unless and until the

Company shall have notified Parent that it has terminated negotiations in respect of the UCB Proposals.

NOW, THEREFORE, Parent hereby agrees that, upon

(and subject only to) payment of the Parent Termination Fee by or on behalf of the Company in connection with the entry into any Permitted Alternative Agreement with UCB, neither Parent nor any of its Affiliates shall have any further claim against

the Company, UCB or any of their respective Affiliates in respect of the Agreement, the Contemplated Transactions or the termination thereof or Company Stockholder Support Agreement in connection therewith, and that none of the Company, UCB or any

of their respective Affiliates shall have any liability or obligation thereunder or in connection therewith.

NOW, THEREFORE, the Company and UCB

severally and not jointly agree that, upon the termination of the Agreement by the Company in connection with the entry into any Permitted Alternative Agreement with UCB, neither the Company nor UCB nor any of their respective Affiliates shall have

any further claim against Parent or any of its Affiliates in respect of the Agreement, the Contemplated Transactions or the termination thereof or Parent Stockholder Support Agreement in connection therewith, and that none of Parent or any of its

Affiliates shall have any liability or obligation thereunder or in connection therewith.

Except as expressly provided herein, the provisions of the

Agreement shall not be affected hereby and shall remain in full force and effect. The provisions of Section 10 of the Agreement (as applicable) shall govern this Waiver.

(Signature Pages Follow)

IN WITNESS WHEREOF, the parties hereto have executed this Waiver as of the date first above written.

RALLYBIO CORPORATION

By:

/s/ Stephen Uden

Name: Stephen Uden

Title: CEO

CANDID THERAPEUTICS, INC.

By:

/s/ Ken Song

Name: Ken Song

Title: CEO

UCB S.A.

By:

/s/ Loic Hameon

Name: Loic Hameon

Title: SVP BD, M&A and Alliance & Integration Management

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