The company has also announced an update of the data from the Phase II trial of palifosfamide used as a single agent in advanced sarcoma.
The Phase I trial of palifosfamide in combination with doxorubicin was fully enrolled with 13 metastatic patients, of whom eight were still receiving therapy. The combination was well tolerated with no dose-limiting toxicities reported during a total of 51 cycles of treatment. Of 12 evaluable patients, three had partial responses. Of the eight patients with soft tissue sarcoma (STS), two had partial responses and the remaining six patients were progression free with a median duration of follow-up of 15 weeks and were still on therapy.
The update from the Phase II trial investigating palifosfamide as a single agent against advanced STS revealed three-month progression free rates of 45% overall and 55% in ifosfamide-naive patients. The six-month progression free rate was 23% at six months. These data show that palifosfamide is highly active in STS.
In both studies, none of the 19 patients who have been treated with the novel palifosfamide-T experienced renal toxicity nor bladder toxicity or encephalopathy commonly associated with ifosfamide treatment. As a result of the data generated in these studies, the company has initiated a Phase II randomized controlled trial comparing palifosfamide plus doxorubicin vs. doxorubicin in the front- and second-line treatment setting of STS.
Sant Chawla, lead investigator for the studies, said: “The study results for palifosfamide are highly encouraging. The data indicate palifosfamide is active both as a single agent and in combination and bode very well for the randomized Phase II trial.”