ADVENTRX Pharmaceuticals has announced positive results from preclinical studies using a multidrug treatment regimen including ANX-510 (CoFactor) at the American Association for Cancer Research (AACR) Annual Meeting.
Treatment with a regimen including CoFactor with 5-fluorouracil (5-FU) and capecitabine (Xeloda(R)), an oral prodrug of 5-FU, demonstrated superior inhibition of tumor growth and longer survival, with lower systemic toxicity compared with treatment groups containing leucovorin or capecitabine alone in a colorectal tumor model. An abstract entitled "Antitumor activity and safety of a hybrid treatment regimen of 5,10-methylenetetrahydrofolate, 5-fluorouracil, and capecitabine in a colorectal tumor xenograft model" was presented yesterday by the study's lead author Mark Cantwell, Ph.D., the Company's vice president of research and development.
"We believe CoFactor has the potential to improve fluoropyrimidine chemotherapies and reduce toxicity in multiple treatment regimens," said Evan M. Levine, ADVENTRX chief executive officer. "Based on these and other data, we are continuing to evaluate various treatment combinations to identify additional commercial opportunities and expand the value of CoFactor."
Tumor-bearing mice treated with CoFactor, 5-FU and capecitabine had the greatest inhibition of tumor growth compared to the other drug regimens tested in this study, including capecitabine alone and a matched treatment regimen of leucovorin (LV), 5-FU, and capecitabine. The mean tumor volume of the CoFactor, 5-FU and capecitabine-treated mice (288.5 mm3 +/- 32.6, mean +/- SEM) was statistically significantly less (p < 0.05) than mice treated with either capecitabine alone (461.0 mm3 +/- 50.4) or mice treated with LV, 5-FU and capecitabine (447.8 mm3 +/- 46.5). Consistent with superior inhibition of tumor growth, treatment with CoFactor, 5-FU and capecitabine also prolonged survival compared to the other treatment regimens. The median survival of CoFactor, 5-FU and capecitabine treated mice (60 days) was statistically significantly longer (p < 0.05) than capecitabine alone (38 days) and LV, 5-FU and capecitabine (39 days). Importantly, the increased tumor inhibition and survival benefits of treatment with CoFactor, 5-FU and capecitabine did not come at the cost of added toxicity. Treatment with CoFactor, 5-FU and capecitabine caused less severe weight loss than all other drug treatments, including capecitabine alone. These results suggest a hybrid treatment regimen, consisting of a CoFactor and 5-FU treatment backbone coupled with capecitabine, might confer improvements in antitumor activity and survival without corresponding increases in systemic toxicity in patients with colorectal cancer. The Company plans to pursue further testing of this CoFactor treatment regimen.