UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.     )

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KINIKSA PHARMACEUTICALS, LTD.
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(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be Held on May 29, 2019. KINIKSA PHARMACEUTICALS, LTD. You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of KINIKSA PHARMACEUTICALS, LTD. CLARENDON HOUSE 2 CHURCH STREET HAMILTON HM11, BERMUDA the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. proxy materials and voting instructions. E75948-P23578 See the reverse side of this notice to obtain Meeting Information Meeting Type:Annual Meeting For holders as of:April 12, 2019 Date: May 29, 2019Time: 7:30 AM, Atlantic Time Location: Fairmont Southampton Hotel 101 South Shore Road Southampton SN02, Bermuda

Before You Vote How to Access the Proxy Materials Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the by the arrow XXXX XXXX XXXX XXXX (located on the following page) in the subject line. How To Vote Please Choose One of the Following Voting Methods marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions. E75949-P23578 Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession of proof of ownership of the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. Proxy Materials Available to VIEW or RECEIVE: NOTICE AND PROXY STATEMENTANNUAL REPORT How to View Online: following page) and visit: www.proxyvote .com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*: sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 15, 2019 to facilitate timely delivery.

The Board of Directors recommends you vote FOR the following proposals: 1. Election of Class I Directors Nominees: 2. The appointment of PricewaterhouseCoopers LLP as the Company’s auditor until the close of the Company’s next Annual Meeting of Shareholders, the delegation to the Company’s Board of Directors, through its Audit Committee, of the authority to set the auditor’s remuneration for such period, and the ratification of the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2019. 1a. Sanj K. Patel 1b. Thomas R. Malley 1c. Richard S. Levy Election of Class II Directors Nominees: NOTE: Such other business as may properly come before the meeting or any continuation, adjournment or postponement thereof. 1d. Stephen R. Biggar 1e. Barry D. Quart Election of Class III Directors Nominees: 1f. Felix J. Baker 1g. Tracey L. McCain 1h. Kimberly J. Popovits E75950-P23578 Voting Items

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