A new chemotherapy combination for colorectal cancer

This study examined the effectiveness and safety of a new chemotherapy combination including oxaliplatin, irinotecan, and S-1 for the treatment of metastatic colorectal cancer.

For several years, standard chemotherapy for metastatic colorectal cancer (a cancer which has spread to other organs) included a combination of drugs referred to as FOLFOXIRI. This combination includes three chemotherapy agents; 5-fluorouracil, oxaliplatin, and irinotecan. While the FOLFOXIRI combination was shown to be the more effective than other chemotherapy regimens, many patients experience cancer progression despite treatment, and survival among metastatic patients remains low.

A new chemotherapy agent, called S-1, has recently been developed. S-1 is similar to 5-fluorouracil, but with two theoretical advantage; it also contains an inhibitor of the protein that breaks down the drug, and it is taken orally instead of by intravenous infusions. While previous studies have demonstrated that S-1 is as effective as 5-fluorouracil, the effect of S-1 in combination with other chemotherapy agents is largely unknown. A new triplet regimen called TIROX combines oxaliplatin and irinotecan with S-1, and is currently under investigation.

This study included 42 patients diagnosed with colon or rectal cancer. TIROX was delivered in 3-week cycles, and up to 12 treatment cycles were delivered to each patient.

A measurable response, or shrinkage of the tumor, was seen in 67.4% of the patients treated with TIROX. The average progression-free survival time, or the amount of time before the cancer continued to grow, was 10 months. On average, overall survival time was 19.2 months. The most common side effect, seen in 45.2% of patients, was neutropenia (low levels of white blood cells).

This study concluded that TIROX is a safe and effective chemotherapy regimen for patients with inoperable or metastatic colorectal cancer.

This small, early phase, study only assessed response to TIROX, but did not perform a controlled comparison between TIROX and other chemotherapy regimens.

Consult with your physician regarding the effectively of new chemotherapy regimens such as TIROX.