This Amendment No. 5 (this “Amendment”) amends and supplements the
Solicitation/Recommendation Statement on Schedule 14D-9 filed by Zogenix, Inc., a Delaware corporation, with the United States Securities and Exchange Commission (the “SEC”) on
February 1, 2022 (as amended or supplemented from time to time, the “Schedule 14D-9”), relating to the tender offer (the “Offer”) by Zinc Merger Sub, Inc., a Delaware
corporation (“Purchaser”) and a wholly owned subsidiary of UCB S.A., a société anonyme formed under the laws of Belgium (“Parent”), to purchase all of the outstanding shares of common stock, par
value $0.001 per share, of the Company (the “Shares”), at a purchase price equal to (i) $26.00, net to the seller in cash, without interest and subject to any withholding of taxes required by applicable law, plus (ii) one non-transferable contingent value right per Share (each, a “CVR”), which CVR represents the right to receive a contingent payment of $2.00, net to the seller in cash, without interest and less any
applicable tax withholding, which amount will become payable, if at all, if a specified milestone is achieved on or prior to December 31, 2023, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated
February 1, 2022 (as amended or supplemented from time to time, the “Offer to Purchase”), and in the related Letter of Transmittal (which, together with the Offer to Purchase, as each may be amended or supplemented from time to
time, constitute the “Offer”). The Offer is described in a Tender Offer Statement on Schedule TO filed by Parent and Purchaser with the SEC on February 1, 2022 (as amended or supplemented from time to time, the
“Schedule TO”). The Offer to Purchase and Letter of Transmittal are filed as Exhibits (a)(1)(A) and (a)(1)(B), respectively, to the Schedule 14D-9 and are incorporated herein by reference.
Except to the extent specifically provided in this Amendment, the information set forth in the Schedule 14D-9
remains unchanged. Capitalized terms used, but not otherwise defined, in this Amendment shall have the meanings ascribed to them in the Schedule 14D-9. This Amendment is being filed to reflect certain updates
as reflected below.
Item 2. Identity and Background of Filing Person.
Item 2 of the Schedule 14D-9 is hereby amended and supplemented as follows:
The eighth paragraph under the heading entitled “Item 2. Identity and Background of Filing Person—Tender Offer” on page 3 of the Schedule 14D-9 is amended and supplemented by replacing “one minute after 11:59 p.m., eastern time, on March 1, 2022” with “5:00 p.m., eastern time, on March 4, 2022”.
Item 4. The Solicitation or Recommendation.
Item 4 of the Schedule 14D-9 is hereby amended and supplemented as follows:
The section entitled “Item 4. The Solicitation or Recommendation—Background and Reasons for the Company Board’s
Recommendation—Background of the Offer” of the Schedule 14D-9 is amended and supplemented by inserting the following paragraph at the end of the section on page 23 before the subheading “Reasons
for the Recommendation of the Company Board”:
On February 28, 2022, as agreed between the Company and Parent, Purchaser extended the
expiration of the Offer. The Offer was previously scheduled to expire at one minute after 11:59 p.m., eastern time, on March 1, 2022. The expiration time of the Offer has been extended to 5:00 p.m., eastern time, on March 4, 2022, unless
further extended.
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