Biweekly TAS-102 Dosing Reduces Toxicity While Maintaining Effectiveness in Colorectal Cancer Treatment

Recent research has demonstrated that administering TAS-102, a chemotherapy drug also known as Lonsurf, on a biweekly schedule can effectively treat metastatic colorectal cancer with fewer side effects. A study published in The Oncologist and led by Dr. Christopher G. Cann from Fox Chase Cancer Center examined 61 patients who received the drug on days 1-5 and then again on days 15-19 within a 28-day cycle, deviating from the standard dosing regimen.

Typically, TAS-102 is given twice daily for five days in a row, followed by a 14-day rest period, a schedule that often causes significant bone marrow suppression. This side effect can lead to dose reductions, treatment delays, and the use of supportive medications like G-CSF, which itself may cause complications such as bone pain.

The study found that the biweekly dosing schedule maintained the drug's efficacy in controlling cancer progression while significantly reducing the incidence of bone marrow suppression and treatment delays. Importantly, none of the patients on this schedule required G-CSF or developed neutropenic fever, a potentially life-threatening condition.

Dr. Cann emphasized that this alternative dosing approach may be particularly beneficial for older patients or those experiencing toxicity from standard schedules. The reduced toxicity profile also enables easier combination with other chemotherapeutics.

While these findings are promising, further prospective and multicenter studies are necessary to confirm the benefits and potentially adopt this dosing strategy more widely.

Source: https://medicalxpress.com/news/2025-06-biweekly-dose-tas-toxicity-effective.html