The combination of the novel drug TH-302 with the standard drug gemcitabine has shown early signs of delaying the worsening of cancer in patients with advanced pancreatic cancer, a Mayo Clinic-led study has found. This was evaluated using a measure termed progression-free survival (PFS). According to the results of a multi-center Phase II clinical trial, patients receiving the combination of gemcitabine and TH-302 demonstrated a progression-free survival of 5.6 months compared to 3.6 months in those patients who received gemcitabine alone.
The two-month delay in worsening of the cancer is considered significant given that the average survival of patients with advanced pancreatic cancer is only six to seven months.
Lead researcher Mitesh Borad, M.D., of Mayo Clinic in Arizona, will present the results of the Phase II study on Monday, April 2, at the American Association for Cancer Research (AACR) Annual Meeting.
The scientific basis of using TH-302 is to target low-oxygen (hypoxic) areas in cancers that are a common source of drug resistance to conventional chemotherapy drugs. Promising results of the combination of TH-302 and gemcitabine in pancreatic cancer animal models preceded this clinical trial in patients.
The Phase II clinical trial included 214 patients from June 2010 to June 2011 at 45 centers. Patients were randomized to receive standard therapy with gemcitabine or gemcitabine in combination with one of two doses of TH-302.
“The results of the trial support ongoing study of TH-302 in pancreatic cancer,” says Dr.Borad.
The study was funded by Threshold Pharmaceuticals, the manufacturer of TH-302.