(CCXI) CCX168, C5a Receptor Inhibitor, Granted Orphan-Drug Designation

MOUNTAIN VIEW, Calif., Nov. 20, 2014  — ChemoCentryx, Inc., (Nasdaq:CCXI), a clinical-stage biopharmaceutical company focused on autoimmune diseases, inflammatory disorders and cancer, reported today that the U.S. Food and Drug Administration (FDA) has granted orphan-drug designation for CCX168, an orally administered inhibitor targeting the receptor for the complement protein known as C5a (C5aR). The designation is for the treatment of atypical Hemolytic Uremic Syndrome (aHUS). Atypical hemolytic uremic syndrome is a rare, life-threatening, progressive disease, frequently with a genetic component, that primarily affects kidney function.

“Given the life-threatening nature of aHUS, we are very pleased with the granting of orphan-drug designation for CCX168 in this disease,” said Thomas J. Schall, Ph.D., President and Chief Executive Officer, ChemoCentryx. “We are committed to supporting the community of patients with aHUS and look forward to starting our clinical studies in this disease in the coming weeks.”

ChemoCentryx has generated positive preclinical data that suggest an important role of C5a receptor inhibition in reducing micro vasculature thrombosis formation in aHUS. The Company plans to initiate a Phase II proof-of-concept study in patients with aHUS by the end of 2014.

About Orphan-Drug Designation

Orphan-Drug Designation by the FDA is granted to novel drugs that treat a rare disease or condition affecting fewer than 200,000 patients in the U.S. The designation provides the drug developer with a seven year period of U.S. marketing exclusivity upon marketing approval for the designated indication, as well as with tax credits for clinical research costs, the ability to apply for annual grant funding, clinical research trial design assistance and the waiver of prescription drug user fees.

About atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome, or aHUS, a life threatening disease that causes chronic blood vessel damage, thrombosis or clotting within blood vessels, hemolysis or red blood cell rupture, and sudden, progressive organ failure, such as kidney failure. The disease is caused by genetic defects in factors that control the activation of the complement system. Current treatment options are still quite limited and prognosis and quality of life are extremely poor.

About ChemoCentryx

ChemoCentryx, Inc. is a clinical-stage biopharmaceutical company focused on discovering, developing and commercializing orally-administered therapeutics that target the chemokine and chemoattractant systems in order to treat autoimmune diseases, inflammatory disorders and cancer. The chemokine system is a biological network that regulates inflammation via a collection of secreted chemokine molecules, or ligands, and their specific cell surface receptors. Based on its proprietary drug discovery and drug development platform, ChemoCentryx has generated multiple clinical and preclinical-stage programs, each targeting distinct chemokine and chemoattractant receptors with different small molecule compounds. CCX140, a CCR2 inhibitor, has been shown to be safe and well tolerated while demonstrating clinical activity on glycemic indices in a Phase II clinical trial in type 2 diabetics, and is now in Phase II clinical development for the treatment of diabetic nephropathy. CCX168, a C5aR inhibitor, is in Phase II development for the treatment of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). CCX168 appears to be safe, well tolerated and successful in allowing both reduction and elimination of high-dose corticosteroids, part of standard of care for AAV patients, without compromising efficacy or safety during a 12-week treatment period. Vercirnon (also known as Traficet-EN or CCX282) is a specific CCR9 inhibitor for the treatment of inflammatory bowel disease. Other clinical programs include CCX872, a next generation CCR2 inhibitor currently in Phase I clinical development, CCX507, a next generation CCR9 inhibitor, which has successfully completed Phase I development and CCX354, a CCR1 inhibitor which successfully completed a Phase II clinical trial for the treatment of rheumatoid arthritis. ChemoCentryx also has several programs in advanced preclinical development.

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” or “continue” or the negative of these terms or other comparable terminology are intended to identify forward-looking statements. These statements include statements regarding whether CCX168 will obtain regulatory approval or the speed with which such approval might be obtained. 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 Quarterly Report on Form 10-Q filed with the SEC November 6, 2014 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.

Source: ChemoCentryx (CCXI-G)

CONTACT: Susan M. Kanaya
         Senior Vice President, Finance and
         Chief Financial Officer or
         Markus J. Cappel, Ph.D.
         Chief Business Officer
         650.210.2900
         investor@chemocentryx.com

         Media:
         Denise Powell
         510.703.9491
         denise@redhousecomms.com

         Investors:
         Angeli Kolhatkar
         Burns McClellan
         212.213.0006
         akolhatkar@burnsmc.com