There is no universally agreed upon second line treatment for metastatic pancreatic cancer. On August 20 in the British Journal of Cancer, the results of an interesting international Phase II clinic trial using nanoliposomal irinotecan for the treatment of earlier pre-treated metastatic pancreatic cancer were published. The researchers included Dr. Margaret Tempero, who is on our Pancreatica Science Board.
The study included 40 patients with metastatic pancreatic cancer who were now considered refractory to earlier treatment with gemcitabine, and who were then given the drug agent PEP02, also known as MM-398 (or Irinotecan Sufosulcrate) as developed by the biotech companies PharmaEngine and Merrimack. This is a nanoliposome, which indicates that the drug molecule is contained in a spherical coating of a lipid or fatty-like substance.
The essential aim of this study was to ascertain the 3-month survival rate. The researchers observed 3 patients who demonstrated an objective tumor response. Over at least two treatment cycles 17 other patients showed evidence of stable disease. 10 patients (of 32) with elevated CA19-9 levels, showed a greater than fifty percent decrease in these levels. The median progression-free duration was 2.4 months. The overall 3-month survival rate was 75%. And the median overall survival was 5.2 months.
The researchers note that the more common side-effects of this treatment were asthenia, abdominal discomfort, neutropenia and diarrhea.
The authors conclude that at this stage of study the apparent activity of liposomal irinotecan coupled with a relatively tolerable side-effect profile make it a promising candidate for second-line consideration. Currently Phase III trials are underway.
Dale O’Brien, MD