ChemoCentryx Raises $33 Million in Private Financing

June 17, 2004; San Carlos, Calif. — ChemoCentryx, Inc. today announced that it has closed a private financing round raising gross proceeds of $33 million. HBM BioVentures and Alta Partners acted as significant new investors in the round. Additional participants included new investors GIMV and Hanseatic, as well as returning investors Techne Corporation, OrbiMed Advisors, HealthCap, and Pictet.

"ChemoCentryx has a mature pipeline of clinical stage programs with an impressive preclinical portfolio," said Gary T. Shearman, Ph.D., U.S. Investment Advisor for HBM BioVentures. "We feel ChemoCentryx is a strong investment based on their core expertise in chemokines, drug discovery and development capabilities, validation by high quality partners and strong leadership. This company has a proven ability to strategically manage resources to achieve maximum return, as demonstrated by their product development accomplishments to date."

Proceeds from the financing will be used to support the development of ChemoCentryx's portfolio of small molecule preclinical and clinical-stage compounds, each targeting specific receptors in the chemokine system. ChemoCentryx recently completed Phase I clinical studies of its lead, unpartnered anti-inflammatory compound, Traficet-EN^™, for Inflammatory Bowel Disease (IBD). This product is anticipated to move into Phase II studies in the second half of 2004. ChemoCentryx is also advancing novel oral medicines for cancer, psoriasis, atherosclerosis and transplant rejection. The company plans to advance one product into clinical testing every twelve to eighteen months.

"We are very pleased to have such strong backing from a group of top-tier investors, including support from the East and West Coast, as well as Europe," said Thomas J. Schall, Ph.D.,

President and CEO of ChemoCentryx. "Over the past year, ChemoCentryx has met all its major milestones - initiating clinical studies for our Traficet-EN^™ product and signing a major partnership with Forest Labs. Delivering on our promises on both the science and business side allowed us to complete this financing with world-class investors on favorable terms. We look forward to sharing updates on our continued growth and clinical accomplishments."

"Chemokine-targeted drugs are emerging as an exciting new class of treatments for numerous major unmet medical needs and ChemoCentryx has an unparalleled position in this field," said Ed Hurwitz of Alta Partners. "The company's world-class research capabilities, strong corporate and academic endorsements and its emerging pipeline of potential blockbuster drugs attracted us to this investment. Over the next few years, we expect further clinical progress on several of the company's drug candidates to make ChemoCentryx one of the most attractive late-stage biopharmaceutical companies in the industry."

ChemoCentryx is building a balanced pipeline of small molecule, orally available compounds for internal development and for co-development with partners. The company's chemokine-based therapeutics correct or modify inappropriate immune system response by binding to the precise chemokine receptor associated with the processes underlying a given condition. Earlier this year, ChemoCentryx announced the formation of a co-development collaboration with Forest Laboratories for the company's oral CCR1 receptor antagonist for the treatment of inflammatory diseases such as rheumatoid arthritis and multiple sclerosis. In addition, the company's partner, Tularik (an AMGEN subsidiary), is conducting Phase II clinical studies for T487, a CXCR3 antagonist for psoriasis that originated from ChemoCentryx research.

About HBM BioVentures Ltd
HBM BioVentures is a leading investment company in the biotech and medical technology sectors. It offers investors access to a broadly diversified portfolio of private and public companies with high value creation potential. HBM BioVentures is appreciated as a complement to traditional pharmaceutical and biotech investments. With net assets of more than USD 700 million, HBM BioVentures is a market leader in its sectors. HBM BioVentures is domiciled in Baar, Switzerland.

About Alta Partners
Alta Partners was founded in 1996 by four of the senior partners of Burr, Egan, Deleage & Co. (BEDCO), a pioneering venture capital firm formed in 1979 that focused on early-stage investing in life sciences, information technology, and communications. Alta Partners currently manages seven funds aggregating approximately $1.5 billion in committed capital, investing in life sciences and information technology. For more information please visit us online at www.altapartners.com

About ChemoCentryx
ChemoCentryx, Inc. discovers, develops and commercializes novel small molecule medicines for autoimmune diseases, inflammatory disorders, cancer and infectious disease. ChemoCentryx has advanced Traficet-EN^™, the company's orally active drug for inflammatory bowel disease, into Phase I clinical trials. Other programs include emerging drug candidates for cancer and cardiopulmonary inflammation. ChemoCentryx's first lead compound, an oral treatment for psoriasis, entered into Phase II clinical study initiated by the company's partner, Tularik. In addition, an orally active development candidate for rheumatoid arthritis and multiple sclerosis is the subject of the company's collaboration with Forest Laboratories. Leveraging its leadership in chemokine-based drug discovery, ChemoCentryx focuses on new classes of orally active small molecules to selectively inhibit activity of the chemokine system, the "master regulator" of immune response. Based in San Carlos, California, ChemoCentryx is privately held. For more information on the company, visit www.chemocentryx.com.

Any statements in this press release about ChemoCentryx's expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and are forward-looking statements. These statements are often, but not always, made through the use of words or phrases such as "believe," "will," "expect," "anticipate," "estimate," "intend," "plan," and "would." Forward-looking statements are not guarantees of performance. They involve known and unknown risks, uncertainties and assumptions that may cause actual results, levels of activity, performance or achievements to differ materially from any results, levels of activity, performance or achievements expressed or implied by any forward-looking statement. Some of the risks, uncertainties and assumptions that could cause actual results to differ materially from estimates or projections contained in the forward-looking statements include but are not limited to (i) the timing, success and cost of preclinical research and clinical studies, (ii) the timing, acceptability and review periods for regulatory filings, (iii) the availability of corporate partners, (iv) uncertainties relating to patent protection and intellectual property rights of third parties, (v) the impact of competitive products and technological changes, (vi) the availability of capital and the cost of capital, (vii) other vagaries in the biotechnology industry and (viii) other risks. ChemoCentryx undertakes no obligation to update or revise any forward-looking statements.