The results of the phase I/II study into immuno-monitoring in Crohn’s disease (CATS1) with TxCell’s leading product candidate Ovasave(R)., performed on 20 patients, were presented at the seventh European Crohn’s and Colitis Organization meeting, in Barcelona, held February 16 -18.
The CATS1 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 CATS1 study included patients with severe chronic active Crohn’s disease, who had failed current treatments, including multiple biologics. An immuno-monitoring study of CATS1 patients was performed in order to evaluate the potential impact of Ovasave(R) on the patient’s immune system. Results indicate that the Ovasave(R) treatment impacted the immune system specifically in patients responding to Ovasave(R) with a decrease in blood pro-inflammatory monocytes subpopulations and with an inhibition of the immune response to Ovasave(R)-specific antigen. The correlation between patient’s clinical improvement and antigen-specific immuno-suppression is supportive of the mechanism of action of Ovasave(R), composed of antigen-specific Treg cells.
“The antigen-specificity of the Treg cells in Ovasave(R) represents an important component of their therapeutic potential,” said Arnaud Foussat, chief scientific officer at TxCell. “Our immuno-monitoring results indicate that antigen-specific immune suppression was obtained in patients responding to the treatment.”
“In addition to the positive clinical results of the phase I/II, the immuno-monitoring data adds important information to the mechanism of action of Ovasave(R),” added François Meyer, chief executive officer at TxCell. “The confirmation of this antigen-specific suppressive activity in the planned phase II clinical trial in the same refractory patient population could become an important marker to assess the patient’s biologic response to treatment.”
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 refractory 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 10^6, 10^7, 10^8 and 10^9 cells.