PHY906 in Colorectal Cancer

Colorectal cancer is the second deadliest cancer in the U.S. The FDA has currently approved the chemotherapeutics 5-fluorouracil (5-FU), capecitabine, CPT-11 (irinotecan), oxaliplatin, cetuximab, and bevacizumab for treating this cancer. Diarrhea, nausea, and vomiting have been identified as common side effects among patients who receive some of these chemotherapies.

When used in conjunction with several of the FDA-approved chemotherapies, preclinical results reveal that PHY906 enhances the antitumor activities of CPT-11 (Figure 1), 5-FU, capecitabine, CPT-11/5-FU/LV, oxaliplatin, and oxaliplatin/5-FU/LV. Furthermore, PHY906 reduces the toxicities of these chemotherapeutic agents in mouse models (Figures 2, 3, and 4).

A phase I/II trial of PHY906 with CPT-11 or CPT-11 + cetuximab will be initiated in the U.S. in Q3/Q4 2005. A phase I/II trial of PHY906 with CPT-11/5-FU/LV or CPT-11 alone closed in 2003.

Figure 1. PHY906 Enhances Anticancer Activities of

Chemotherapeutic Agents

Colon 38-bearing BDF-1 female mice were treated intraperitoneally with CPT-11. While there was no statistical effect of PHY906 alone on tumor growth, there was a statistical trend that PHY906 could enhance the effectiveness and synergize with the effects of CPT-11 (P< 0.001).