CCXI ChemoCentryx Inc

ChemoCentryx, Inc., (Nasdaq: CCXI), today announced two upcoming poster presentations for CCX559, the Company’s investigational, highly potent, orally administered PD-L1 checkpoint inhibitor, at the Society for Immunotherapy of Cancer (SITC) 37th Annual Meeting, held November 8-12, 2022, in Boston, MA.

ChemoCentryx Poster Presentations at SITC 37th Annual Meeting (November 8-12, 2022):

Results From an Ongoing Open-Label, Multicenter, Phase 1 Trial of CCX559, an Orally Administered Small Molecule PD-L1 Inhibitor, in Patients with Advanced Solid Tumors

Abstract Number: 769Location: Hall CPresentation Time: November 10, 2022, 11:40 a.m. – 1:10 p.m. ETPoster Viewing Time: November 10, 2022, 9:00 a.m. – 9:00 p.m. ET

The Small Molecule PD-L1 Inhibitor CCX559 Preferentially Accumulates in Tumors, Resulting in Depletion of Cell-Surface PD-L1 in a Murine Preclinical Model

Abstract Number: 499Location: Hall CPresentation Time: November 10, 2022, 11:40 a.m. – 1:10 p.m. ETPoster Viewing Time: November 10, 2022, 9:00 a.m. – 9:00 p.m. ET

About CCX559

CCX559 is a highly potent orally administered small molecule PD-L1 checkpoint inhibitor. Preclinical characterization has demonstrated that CCX559 blocks binding to PD-1 and CD80, and prevents PD-L1 inhibition of T cell activation. CCX559, when orally administered in animal models, demonstrated anti-tumor efficacy, including the ability to induce complete responses.

The PD-L1/PD-1 interaction is one of the major immune checkpoints that limits the ability of effector T cells to destroy cancer cells. As a potential next generation therapy, an orally administered small molecule inhibitor of PD-L1 could have advantageous properties compared to approved monoclonal antibodies, such as better penetration into solid tumors, reduced immunogenicity, lack of Fc-mediated side effects and convenience of oral administration.

During 2021, ChemoCentryx initiated a first-in-human Phase I dose escalation study to evaluate the safety, tolerability, PK, and PD of CCX559 in patients with various types of advanced cancer. In early 2023, the Company plans to advance CCX559 into a Phase Ib/II clinical trial to measure anti-tumor effects of CCX559 more directly.

About ChemoCentryx

ChemoCentryx is a biopharmaceutical company commercializing and developing new medications for inflammatory and autoimmune diseases and cancer. ChemoCentryx targets the chemokine and chemoattractant systems to discover, develop and commercialize orally administered therapies. In the United States, ChemoCentryx markets TAVNEOS® (avacopan), the first approved orally administered inhibitor of the complement 5a receptor as an adjunctive treatment for adult patients with severe active ANCA-associated vasculitis. TAVNEOS is also in late-stage clinical development for the treatment of severe hidradenitis suppurativa (HS) and C3 glomerulopathy (C3G).

ChemoCentryx is also developing CCX559, a highly potent orally administered small molecule PD-L1 checkpoint inhibitor, for the treatment of patients with solid tumors. A Phase I dose escalation study for CCX559 is ongoing and ChemoCentryx plans to advance to a Phase Ib/II study in early 2023.

Additionally, ChemoCentryx has early-stage drug candidates that target chemoattractant receptors in other inflammatory and autoimmune diseases and in cancer. For more information about the Company visit www.ChemoCentryx.com.

TAVNEOS® is a registered trademark of ChemoCentryx, Inc. For more information, please see the Full Prescribing Information and Medication Guide, available at TAVNEOS.com.

Forward-Looking Statements

ChemoCentryx cautions that statements included in this press release that are not a description of historical facts are forward-looking statements. Words such as "may," "could," "will," "would," "should," "expect," "plan," "anticipate," "believe," "estimate," "intend," "predict," "seek," "contemplate," "potential," "continue" or "project" or the negative of these terms or other comparable terminology are intended to identify forward-looking statements. These statements include the Company's statements regarding the achievement of anticipated goals and milestones. The inclusion of forward-looking statements should not be regarded as a representation by ChemoCentryx that any of its plans will be achieved. Actual results may differ from those set forth in this release due to the risks and uncertainties inherent in the ChemoCentryx business and other risks described in the Company's filings with the Securities and Exchange Commission ("SEC"). Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and ChemoCentryx undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof. Further information regarding these and other risks is included under the heading "Risk Factors" in ChemoCentryx's periodic reports filed with the SEC, including ChemoCentryx's Annual Report on Form 10-K filed with the SEC on March 1, 2022, and its other reports which are available from the SEC's website (www.sec.gov) and on ChemoCentryx's website (www.chemocentryx.com) under the heading "Investors." All forward-looking statements are qualified in their entirety by this cautionary statement. This caution is made under the safe harbor provisions of Section 21E of the Private Securities Litigation Reform Act of 1995.

ChemoCentryx Contacts

Investors:Bill Slattery, Jr.Vice President, Investor Relations& Corporate Communications650.210.2970bslattery@chemocentryx.com

Media:Alex StrausInvestor Relations & Corporate Communications Managerastraus@chemocentryx.com