TAS-102 in Metastatic Colorectal Cancer

TAS-102 is an oral investigational compound being evaluated as a treatment for patients with refractory metastatic colorectal cancer (CRC). It is an antimetabolite that is similar to 5-fluorouracil (5-FU), states Howard S. Hochster, MD. In the phase III RECOURSE trial, TAS-102 demonstrated an improvement in survival in heavily pre-treated patients with metastatic colorectal cancer compared with placebo. The drug by itself has a 12-minute half-life and is administered twice daily, 10 days a month.

In February 2015, the FDA accepted a new drug application for TAS-102, based on the RECOURSE trial. For patients treated with TAS-102, the median OS was 7.1 months compared with 5.3 months with placebo (HR = 0.68; P <.0001). The median PFS in the TAS-102 arm was 2 months versus 1.7 months with placebo (HR = 0.48; P <.0001).

The agent is effective in cell lines that are refractory to 5-FU, notes Richard L. Goldberg, MD. Its toxicity profile appears to be more predictable over its main competitor, capecitabine. Toxicities of TAS-102 mainly include mild hematologic toxicity, such as delayed bone marrow recovery.

The drug is likely to move into earlier settings in combination with other agents, predicts Fadi Braiteh, MD. There will be a learning curve in clinical practice, Braiteh adds, but clinical trials will help answer questions as to the drug’s efficacy earlier in the disease course.