CCXI ChemoCentryx Inc

Filed by ChemoCentryx, Inc. pursuant to Rule 14a-12

Under the Securities Exchange Act of 1934

Subject Company: ChemoCentryx, Inc.

Commission File No. of Subject Company: 001-35420

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(RULE 14a-101)

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant  ☒                    Filed by a Party other than the Registrant  ☐

Check the appropriate box:

ChemoCentryx, Inc.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

[The following “frequently asked questions” document was shared with employees of ChemoCentryx, Inc. on August 9, 2022.]

ChemoCentryx Community,

As part of our commitment to continue providing you relevant information in response to your questions, we have attached a second FAQ in our series of conversations and communications about the transaction. We know that you still have some questions, and we will continue to provide you timely information as soon as it is available.

Thank you for your patience and understanding throughout this process. We appreciate and understand your desire for more information. While we are not able to answer every question at this time, we will attempt to answer as many as we can, and we are committed to transparency and communication during the process. For now, it is very important that we all remain focused on runningour business and serving our patients and their families.

General Information

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Impact to Employees

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Business Operations

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Please note that the above is a summary of responses to specific questions and, as always, ChemoCentryx, Amgen and each of their respective affiliates reserve the right to amend or terminate any compensation or benefit plans in accordance with their terms and applicable law, and any summary of any such plan or the merger agreement is qualified in its entirety by the terms of the underlying document. In the event of any conflict between this communication and the underlying document, the underlying document will govern. In addition, your employment is, and continues to be, at will.

Additional Information

This communication may be deemed solicitation material in respect of the proposed acquisition of ChemoCentryx by Amgen. ChemoCentryx expects to file with the Securities and Exchange Commission (the “SEC”) a proxy statement and other relevant documents with respect to a special meeting of the stockholders of ChemoCentryx to approve the proposed merger. INVESTORS OF CHEMOCENTRYX ARE URGED TO READ THE DEFINITIVE PROXY STATEMENT AND OTHER RELEVANT MATERIALS CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT CHEMOCENTRYX, AMGEN AND THE PROPOSED MERGER. Investors may obtain a free copy of these materials (when they are available) and other documents filed by ChemoCentryx with the SEC at the SEC’s website at www.sec.gov, at ChemoCentryx’s website at https://chemocentryx.com or by sending a written request to ChemoCentryx at 835 Industrial Road, Suite 600, San Carlos, CA 94070, Attention: Legal.

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Participants in the Solicitation

ChemoCentryx and its directors, executive officers and certain other members of management and employees may be deemed to be participants in soliciting proxies from its stockholders in connection with the proposed merger. Information regarding the persons who may, under the rules of the SEC, be considered to be participants in the solicitation of ChemoCentryx’s stockholders in connection with the proposed merger will be set forth in ChemoCentryx’s definitive proxy statement for its special stockholders meeting. Additional information regarding these individuals and any direct or indirect interests they may have in the proposed merger will be set forth in the definitive proxy statement when and if it is filed with the SEC in connection with the proposed merger.

Forward-Looking Statements

This communication contains forward-looking statements. These forward-looking statements generally include statements that are predictive in nature and depend on or refer to future events or conditions, and include words such as “expect,” “anticipate,” “outlook,” “could,” “target,” “project,” “intend,” “plan,” “believe,” “seek,” “estimate,” “should,” “may,” “assume” and “continue” as well as variations of such words and similar expressions. By their nature, forward-looking statements involve risks and uncertainty because they relate to events and depend on circumstances that will occur in the future, and there are many factors that could cause actual results and developments to differ materially from those expressed or implied by these forward-looking statements. Forward-looking statements include, among other things, statements about the potential benefits of the proposed acquisition of ChemoCentryx by Amgen (the “proposed transaction”); the prospective performance and outlook of ChemoCentryx’s business, performance and opportunities; any potential strategic benefits, synergies or opportunities expected as a result of the proposed transaction; the ability of the parties to complete the proposed transaction and the expected timing of completion of the proposed transaction; as well as any assumptions underlying any of the foregoing.

These statements are not guarantees of future performance and they involve certain risks, uncertainties and assumptions that are difficult to predict. We caution you that actual outcomes and results may differ materially from what is expressed, implied or forecasted by our forward-looking statements.There can be no guarantee that the proposed transaction will be completed, or that it will be completed as currently proposed, or at any particular time. Neither can there be any guarantee that Amgen or ChemoCentryx will achieve any particular future financial results, or that Amgen will be able to realize any of the potential strategic benefits, synergies or opportunities as a result of the proposed acquisition. In particular, our expectations could be affected by, among other things: the risk that the proposed transaction may not be completed in a timely manner or at all; the possibility that competing offers or acquisition proposals for ChemoCentryx will be made; the possibility that required regulatory, stockholder or other approvals or other conditions to the consummation of proposed transaction may not be satisfied on a timely basis or at all (and the risk that such approvals may result in the imposition of conditions that could adversely affect Amgen or ChemoCentryx or the expected benefits of the proposed transaction); regulatory actions or delays or government regulation generally, including potential regulatory actions or delays relating to the completion of the potential transaction; the occurrence of any event, change or other circumstance that could give rise to the right of Amgen

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or ChemoCentryx to terminate the definitive merger agreement governing the terms and conditions of the proposed transaction; effects of the announcement, pendency or consummation of the proposed transaction on ChemoCentryx’s ability to retain and hire key personnel, its ability to maintain relationships with its customers, suppliers and others with whom it does business, its business generally or its stock price; risks related to the diversion of management’s attention from ongoing business operations and opportunities; the risk that stockholder litigation in connection with the proposed transaction may result in significant costs of defense, indemnification and liability; the potential that the strategic benefits, synergies or opportunities expected from the proposed transaction may not be realized or may take longer to realize than expected; the successful integration of ChemoCentryx into Amgen subsequent to the closing of the proposed transaction and the timing, difficulty and cost of such integration; the possibility that the proposed transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events; and other risks and factors referred to from time to time in Amgen’s and ChemoCentryx’s filings with the Securities and Exchange Commission, including Amgen’s Annual Report on Form 10-K for the year ended December 31, 2021 and subsequent Quarterly Reports on Form 10-Q and ChemoCentryx’s Annual Report on Form 10-K for the year ended December 31, 2021 and subsequent Quarterly Reports on Form 10-Q, including those related to the uncertainties inherent in the research and development of new and existing healthcare products, including clinical and regulatory developments and additional analysis of existing clinical data; our ability to obtain or maintain proprietary intellectual property protection; safety, quality or manufacturing issues or delays; changes in expected or existing competition; and domestic and global trends toward health care cost containment, including government, payor and general public pricing and reimbursement pressures. The effects of the COVID-19 pandemic may give rise to risks that are currently unknown or amplify the risks associated with many of these factors. ChemoCentryx is providing the information in this communication as of this date and does not undertake any obligation to update any forward-looking statements as a result of new information, future events or otherwise.

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Additional Information and Where to Find It

This communication may be deemed solicitation material in respect of the proposed acquisition of ChemoCentryx by Amgen. ChemoCentryx expects to file with the SEC a proxy statement and other relevant documents with respect to a special meeting of the stockholders of ChemoCentryx to approve the proposed Merger. Investors of ChemoCentryx are urged to read the definitive proxy statement and other relevant materials carefully and in their entirety when they become available because they will contain important information about ChemoCentryx, Amgen and the proposed Merger. Investors may obtain a free copy of these materials (when they are available) and other documents filed by ChemoCentryx with the SEC at the SEC’s website at www.sec.gov, at ChemoCentryx’s website at https://chemocentryx.com or by sending a written request to ChemoCentryx at 835 Industrial Road, Suite 600, San Carlos, CA 94070, Attention: Legal.

Participants in the Solicitation

ChemoCentryx and its directors, executive officers and certain other members of management and employees may be deemed to be participants in soliciting proxies from its stockholders in connection with the proposed Merger. Information regarding the persons who may, under the rules of the SEC, be considered to be participants in the solicitation of ChemoCentryx’s stockholders in connection with the proposed Merger will be set forth in ChemoCentryx’s definitive proxy statement for its special stockholders meeting. Additional information regarding these individuals and any direct or indirect interests they may have in the proposed Merger will be set forth in the definitive proxy statement when and if it is filed with the SEC in connection with the proposed Merger.

Cautionary Statement Regarding Forward-Looking Statements

This communication contains forward-looking statements. These forward-looking statements generally include statements that are predictive in nature and depend on or refer to future events or conditions, and include words such as “expect,” “anticipate,” “outlook,” “could,” “target,” “project,” “intend,” “plan,” “believe,” “seek,” “estimate,” “should,” “may,” “assume” and “continue” as well as variations of such words and similar expressions. By their nature, forward-looking statements involve risks and uncertainty because they relate to events and depend on circumstances that will occur in the future, and there are many factors that could cause actual results and developments to differ materially from those expressed or implied by these forward-looking statements. Forward-looking statements include, among other things, statements about the potential benefits of the proposed acquisition of ChemoCentryx by Amgen (the “proposed transaction”); the prospective performance and outlook of ChemoCentryx’s business, performance and opportunities; any potential strategic benefits, synergies or opportunities expected as a result of the proposed transaction; the ability of the parties to complete the proposed transaction and the expected timing of completion of the proposed transaction; as well as any assumptions underlying any of the foregoing.

These statements are not guarantees of future performance and they involve certain risks, uncertainties and assumptions that are difficult to predict. We caution you that actual outcomes and results may differ materially from what is expressed, implied or forecasted by our forward-looking statements. There can be no guarantee that the proposed transaction will be completed, or that it will be completed as currently proposed, or at any particular time. Neither can there be any guarantee that Amgen or ChemoCentryx will achieve any particular future financial results, or that Amgen will be able to realize any of the potential strategic benefits, synergies or opportunities as a result of the proposed acquisition. In particular, our expectations could be affected by, among other things: the risk that the proposed transaction may not be completed in a timely manner or at all; the possibility that competing offers or acquisition proposals for ChemoCentryx will be made; the possibility that required regulatory, stockholder or other approvals or other conditions to the consummation of proposed transaction may not be satisfied on a timely basis or at all (and the risk that such approvals may result in the imposition of conditions that could adversely affect Amgen or ChemoCentryx or the expected benefits of the proposed transaction); regulatory actions or delays or government regulation generally, including potential regulatory actions or delays relating to the completion of the potential transaction; the occurrence of any event, change or other circumstance that could give rise to the right of Amgen or ChemoCentryx to terminate the definitive merger agreement governing the terms and conditions of the proposed transaction; effects of the announcement, pendency or consummation of the proposed transaction on ChemoCentryx’s ability to retain and hire key personnel, its ability to maintain relationships with its customers, suppliers and others with whom it does business, its business generally or its stock price; risks related to the

diversion of management’s attention from ongoing business operations and opportunities; the risk that stockholder litigation in connection with the proposed transaction may result in significant costs of defense, indemnification and liability; the potential that the strategic benefits, synergies or opportunities expected from the proposed transaction may not be realized or may take longer to realize than expected; the successful integration of ChemoCentryx into Amgen subsequent to the closing of the proposed transaction and the timing, difficulty and cost of such integration; the possibility that the proposed transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events; and other risks and factors referred to from time to time in Amgen’s and ChemoCentryx’s filings with the Securities and Exchange Commission, including Amgen’s Annual Report on Form 10-K for the year ended December 31, 2021 and subsequent Quarterly Reports on Form 10-Q and ChemoCentryx’s Annual Report on Form 10-K for the year ended December 31, 2021 and subsequent Quarterly Reports on Form 10-Q, including those related to the uncertainties inherent in the research and development of new and existing healthcare products, including clinical and regulatory developments and additional analysis of existing clinical data; our ability to obtain or maintain proprietary intellectual property protection; safety, quality or manufacturing issues or delays; changes in expected or existing competition; and domestic and global trends toward health care cost containment, including government, payor and general public pricing and reimbursement pressures. The effects of the COVID-19 pandemic may give rise to risks that are currently unknown or amplify the risks associated with many of these factors. ChemoCentryx is providing the information in this communication as of this date and does not undertake any obligation to update any forward-looking statements as a result of new information, future events or otherwise.