ChemoCentryx Reports Pharmacokinetic and Pharmacodynamic Results from Ongoing Phase I Trial of Orally Administered PD-L1 Inhibitor, CCX559, at American Association for Cancer Research (AACR) Annual Meeting 2022

-- Human pharmacokinetics (PK) reveal CCX559 exposure tracking with projections, with good oral availability and expected half-life --

-- Pharmacodynamic (PD) results show CCX559 exhibits immune stimulatory properties in cancer patients --

SAN CARLOS, Calif., April 13, 2022 (GLOBE NEWSWIRE) -- ChemoCentryx, Inc., (Nasdaq: CCXI), today announced the presentation of preclinical data and initial pharmacokinetic (PK) and pharmacodynamic (PD) data from the ongoing Phase I clinical study of CCX559 during a poster session at the American Association for Cancer Research (AACR) Annual Meeting 2022.

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.

Preclinical characterization has demonstrated that CCX559 is a potent inhibitor of PD-L1 that blocks binding to PD-1 and CD80 and prevents PD-L1 inhibition of T cell activation. 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 this Phase I basket study, CCX559 is taken orally once per day at specified dose levels, starting at 30 mg and ranging to date to 120 mg.

In the AACR poster titled, CCX559, an orally administered small molecule PD-L1 inhibitor for the treatment of solid tumors: Initial Pharmacokinetic and Pharmacodynamic Results from the in Progress First-In-Human Trial (abstract #4147), ChemoCentryx reported initial data available to date from patients enrolled in the first three dose cohorts in the ongoing Phase I study. Patients received CCX559 once daily at doses of 30 mg, 60 mg and 120 mg. All patients receiving 120 mg of CCX559 (n=9) were included in the PK evaluation reported in the poster. PD data for seven of the 120 mg patients (i.e., those whose data were available at time of submission) were also presented.

• PK evaluation shows human CCX559 exposure is in line with preclinical projections. The mean exposure at 120 mg CCX559 in patients is comparable to exposures with anti-tumor activity in preclinical models and sufficient for PD-L1 target coverage, the half-life of the drug (enabling predicted once daily dosing) was also in line with projections.
• PD activity results from the first cycle of treatment indicate that CCX559 is immunomodulatory. CD4 and CD8 T cell proliferation increased in all dose groups; soluble PD-L1 levels in plasma were significantly increased in the 120 mg patients by the end of the first cycle of dosing; and plasma IFNγ, CXCL9, CXCL10 were increased in the majority of patients assessed at 120 mg.
• The PD activity of CCX559 is consistent with approved antibody inhibitors of PD-L1, in the extent and kinetics of the observed Th1 responses.
  

ChemoCentryx expects to present additional findings from this ongoing Phase I study at major oncology conferences through 2022. During the second half of 2022, 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). 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, whether the Company's drug candidates, including CCX559, will have better drug properties than approved medicines, such as better penetration into solid tumors, reduced immunogenicity, lack of Fc-mediated side effects and convenience of oral administration, or will be shown to be safe and effective in ongoing or future clinical trials. 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.

Contacts

Investors:
Bill Slattery, Jr.
Vice President, Investor Relations
& Corporate Communications
650.210.2970
[email protected]

Media:
Stephanie Tomei
408.234.1279
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