Point Therapeutics has reported positive interim results for their ongoing Phase II study of talabostat in combination with rituximab, a monoclonal antibody, in patients with advanced chronic lymphocytic leukemia (CLL).
This single-arm trial evaluates talabostat in combination with rituximab in up to 54 evaluable patients with advanced CLL who have failed fludarabine and/or rituximab. Thus far, 36 patients have entered the study and 31 meet criteria for evaluability (at least six days of talabostat with a post-baseline assessment by the investigator). 66.7 percent of the patients in the study are Rai Stage IV, the most advanced CLL patient population. Investigators have reported clinical responses in seven of 31 evaluable patients for an overall response rate of 22.5 percent. One of the seven responses is awaiting follow-up assessment to confirm the response. Five of the seven responses were observed in patients who had previously not responded to or had relapsed following prior treatment with rituximab -- suggesting that the addition of talabostat is providing additive activity. Three of these five patients had not only failed fludarabine and rituximab, but had also failed prior alemtuzumab treatment -- the only approved agent in fludarabine failures.