TxCell presents final positive results of the phase I/II clinical trial with antigen-specific Treg cells in Crohn’s disease

TxCell SA, a biotechnology company developing Treg cell-based immunotherapies for the treatment of severe chronic inflammatory diseases with high unmet medical needs, announces today the presentation of final positive results of the phase I/II study in Crohn’s disease (CATS-1) with its leading product candidate, OvaSave(R). The results of this study, performed on 20 patients, were announced at the United European Gastroenterology Week (UEGW) in Stockholm, held October 22 to 26. The CATS-1 study was a first in man, open label, multicenter phase I/II study in France to evaluate the tolerability and efficacy of OvaSave(R), an antigen-specific regulatory T cell-based immunotherapy. The CATS-1 study was for patients with severe chronic active Crohn’s disease, who had failed current treatments, including multiple biologics. Crohn’s disease is a chronic, often disabling disorder with a significant unmet medical need as existing treatments still do not provide satisfactory relief to patients.

The results presented at the United European Gastroenterology Week show that OvaSave(R) is well tolerated. The results also showed a positive efficacy signal, with 40 per cent of the patients positively responding five weeks after treatment in the overall population group. This positive effect was particularly relevant in the best dose group with 75 per cent of patients responding and 38 per cent remitting five weeks after treatment.
The present evidence has led TxCell to plan the continuation of the clinical development of OvaSave(R) for the treatment of Crohn’s disease with a controlled phase II study.

“The results indicate the potential of our antigen-specific Treg cell approach for the management of multiple chronic inflammatory diseases,” said François Meyer, chief executive officer of TxCell. “160,000 people are affected by severe Crohn’s disease in Europe and US*. Confirmation of these positive results will provide a new hope for patients in a refractory state of the disease.”

“The open label evidence on the tolerance profile and the dose-related significant clinical effect are very encouraging,” said Miguel Forte, chief medical officer of TxCell. “This will be the basis for the next steps in the clinical development plan of OvaSave(R) in Crohn’s disease. The company will initiate a phase II study in the same patient population.”

* According to PharMetrics Analysis, September 2008.

About the phase I/II clinical trial
The concluded 12 week, multicenter, open label, uncontrolled and dose-escalation phase I/II study was designed to evaluate the safety and efficacy of OvaSave(R) therapy in patients with severe and relapsing Crohn’s disease. The product was injected intravenously as a single administration to patients with chronic active Crohn’s disease. Six sites in France enrolled patients distributed into four different groups with doses of 106, 107, 108 and 109 cells.

About OvaSave(R)

OvaSave(R), an antigen-specific Treg cell-based immunotherapy, is TxCell’s leading product candidate for the treatment of inflammatory bowel diseases like Crohn’s disease. The antigen-specific Treg cells utilized in Ovasave(R) are isolated from whole blood of the patient and activated by ovalbumin. The cloned Treg cells are expanded ex vivo before i.v. reinjection into that same patient. The injected Treg cells home to the site of inflammation and are activated locally by the specific food antigen, ovalbumin.

About TxCell

TxCell SA, a spin-off of Inserm (France’s National Institute for Health and Medical Research) located in the technology park of Sophia Antipolis, near Nice in France, is developing cell-based immunotherapies for the treatment of severe chronic inflammatory diseases with high medical need using its unique and proprietary technology platform based on the properties of antigen-specific regulatory T lymphocytes (Treg cells). The company’s lead product candidate is focusing on refractory Crohn’s disease and a second product candidate is in phase I/II clinical evaluation for refractory rheumatoid arthritis. Additional targets including multiple sclerosis are currently in preclinical stage.