ChemoCentryx Inc., a clinical-stage biopharmaceutical company focused on discovering, developing and commercialising orally-administered therapeutics that target the chemokine system, presented data from the company's phase II clinical trial of Traficet-EN (CCX282-B), an orally-active anti-inflammatory agent that targets the chemokine receptor CCR9.

Clinical results demonstrate that Traficet-EN is well tolerated and shows clinical activity in the treatment of patients with active Crohn's disease. These data were presented in an oral session, "Advances in Crohn's disease," at the Digestive Disease Week (DDW) 2007 by Satish Keshav, MD, Gastroenterologist at the John Radcliffe Hospital, Oxford, and a clinical investigator for the study.

"Traficet-EN demonstrated promising evidence of efficacy in the treatment of Crohn's disease patients, particularly among patients with elevated CDAI and CRP measurements at baseline. These results, achieved after only four weeks of treatment, justify broader study of Traficet-EN," said Dr Keshav. "Traficet-EN's potential to control Crohn's disease with a safe and effective oral capsule represents a paradigm shift in the treatment of this condition and a truly meaningful improvement in patient care."

Patients enrolled in the phase II clinical trial were randomised to receive a once-daily 250 mg capsule of Traficet-EN or placebo for 28 days. Both Crohn's Disease Activity Index (CDAI) scores and C-reactive protein (CRP) levels were measured at baseline and on study days 8, 15 and 29. Among a defined subgroup of 39 patients identified as having more active disease, with CDAI scores of greater than or equal to 250 and CRP of greater than 7.5 mg/L at baseline, Traficet-EN demonstrated clinical benefit. Fifty-eight percent of patients in the Traficet-EN group experienced a 70 point or greater drop in CDAI scores compared to 31 percent of those who received placebo.

"We are very pleased to have seen clear signs of clinical activity in this four week study of Traficet-EN. Patients with active disease reported significant improvement in their condition when treated with Traficet-EN compared to those in the control group," said Pirow Bekker, MD, vice president, Medical and Clinical Affairs of ChemoCentryx, Inc. "In addition, the results from this group of patients in our phase II trial are in line with the latest research from key opinion leaders. Current research has shown that CDAI scores of 250 and above, combined with elevated CRP serum levels at baseline, help to identify patients with actual Crohn's disease and may thereby reduce the high placebo response rate frequently observed in Crohn's disease clinical trials. We are currently using these parameters as enrolment criteria in our ongoing long-term clinical study, known as Protect-1, which will evaluate Traficet-EN's ability to induce response or remission, as well as at the drug's potential as maintenance therapy."

The oral presentation of Phase II data, titled "CCX282-B, an orally active inhibitor of chemokine receptor CCR9, shows anti-inflammatory and clinical activity in the treatment of Crohn's Disease" was provided today by Dr Keshav as part of the Advances in Crohn's Disease session. Data from the phase II trial were also selected for presentation during the "Best of UEGW" session sponsored by the American Gastroenterological Association (AGA) yesterday afternoon. The phase II randomised double-blind, placebo-controlled clinical trial was designed to evaluate Traficet-EN's safety and tolerability among patients with moderate-to-severe Crohn's disease.

Traficet-EN was well-tolerated by patients participating in the phase II study and the incidence of adverse events reported was generally similar in both the placebo and Traficet-EN groups.

ChemoCentryx is currently evaluating Traficet-EN in a large multi-national clinical trial. PROTECT-1 or the Prospective Randomised Oral Therapy Evaluation in Crohn's disease Trial is a randomised, double-blind, placebo-controlled study to evaluate the safety and efficacy of Traficet-EN in patients with moderate-to-severe Crohn's disease.