Introduction
This Amendment No. 5 (this “Amendment”) amends and supplements the Rule 13e-3 Transaction
Statement on Schedule 13E-3 (as amended or supplemented from time to time, the “Statement”) initially filed on September 15, 2020 with the Securities and Exchange Commission (the
“SEC”) by Akcea Therapeutics, Inc., a Delaware corporation (“Akcea” or the “Company”), the issuer of the common stock that is the subject of the Rule 13e-3 transaction described below, and relates to the cash tender offer by Avalanche Merger Sub, Inc., a Delaware corporation (“Purchaser”) and a wholly owned subsidiary of Ionis
Pharmaceuticals, Inc., a Delaware corporation (“Ionis”), to purchase all of the issued and outstanding shares of common stock, par value $0.001 per share, of Akcea at a price per Share equal to $18.15, net to the seller of
such Shares in cash, without interest, subject to any withholding of taxes required by applicable law (the “Offer”). The Offer is being made pursuant to the Agreement and Plan of Merger, dated as of August 30, 2020
(together with any amendments or supplements thereto, the “Merger Agreement”), among the Company, Ionis and Purchaser. The Merger Agreement provides that, among other things, following the consummation of the Offer and
subject to the terms and conditions of the Merger Agreement, Purchaser will merge with and into the Company pursuant to Section 251(h) of the General Corporation Law of the State of Delaware (the “DGCL”), with the
Company being the surviving corporation (the “Merger”). The terms of the Offer, and the conditions to which it is subject, are set forth in the combined Tender Offer Statement and Rule
13e-3 Transaction Statement filed under cover of Schedule TO by Purchaser and Ionis on September 14, 2020 (as amended or supplemented from time to time, the “Schedule TO”), which
contains as exhibits an Offer to Purchase dated September 14, 2020 (the “Offer to Purchase”), and the related Letter of Transmittal (the “Letter of Transmittal,” which together with the Offer to
Purchase, as each of them may be amended or supplemented from time to time, contain the terms of the Offer). In response to the Offer, the Company filed a Solicitation/Recommendation Statement on Schedule
14D-9 on September 14, 2020 (as amended or supplemented from time to time, the “Schedule 14D-9”).
The information in the Statement is incorporated into this Amendment by reference to all of the applicable items in the Statement, except that such
information is hereby amended and supplemented to the extent provided in this Amendment. All information contained in this Schedule 13E-3 concerning the Company, Ionis and Purchaser has been provided by such
person and not by any other person. All capitalized terms used in this Schedule 13E-3 without definition have the meanings ascribed to them in the Schedule 14D-9.
The information contained in the Schedule 14D-9 and the Offer to Purchase, including all schedules, annexes and
exhibits thereto, copies of which are attached as exhibits hereto, is expressly incorporated by reference to the extent such information is required in response to the items of this Schedule 13E-3, and is
supplemented by the information specifically provided herein. The responses to each item in this Schedule 13E-3 are qualified in their entirety by the information contained in the Schedule 14D-9 and the Offer to Purchase.
Item 15. Additional Information
Item 15 of the Statement is hereby amended and supplemented to include the following:
“At one minute after 11:59 p.m., Eastern Time, on October 9, 2020, the Offer expired. American Stock Transfer & Trust Company, LLC, in its
capacity as depository for the Offer (the “Depository”), advised that, as of the expiration of the Offer, a total of 21,201,937 Shares (excluding (i) Shares beneficially owned and tendered by Excluded Holders (as defined
in the Schedule 14D-9) and (ii) Shares with respect to which Notices of Guaranteed Delivery were delivered) were tendered and not validly withdrawn pursuant to the Offer, representing approximately 85.5%
of the Shares outstanding as of the expiration of the Offer, excluding the Shares beneficially owned by the Excluded Holders. In addition, the Depository advised that Notices of Guaranteed Delivery have been delivered with respect to 919,068
additional Shares, representing approximately 3.7% of the Shares outstanding as of the expiration of the Offer, excluding the Shares beneficially owned by the Excluded Holders.
As of the expiration of the Offer, the number of Shares tendered and not validly withdrawn pursuant to the Offer satisfied the Minimum Condition, and all
other conditions to the Offer were satisfied or waived. Immediately after the expiration of the Offer, Purchaser irrevocably accepted for payment, and will promptly pay for, all Shares tendered and not validly withdrawn pursuant to Offer.
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