Trifluridine/Tipiracil (TAS-102) With or Without Thalidomide for the Treatment of Metastatic Colorectal Cancer

In the past decade, the use of targeted drugs has greatly improved the overall survival of patients with mCRC. However, there are currently few effective drugs available clinically. Trifluridine/Tipiracil (TAS-102) is a novel cytotoxic antitumor drug taken orally with minor adverse reactions, consisting of trifluridine and tipyrimidine hydrochloride. Tas-102 has been approved for the treatment of patients with metastatic colorectal cancer (mCRC) who have been previously treated with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy; an anti-VEGF biological therapy; and if RAS wild type, an anti-EGFR therapy. Multiple studies have shown that TAS-102 prolongs median OS and PFS in mCRC patients compared with placebo. Thalidomide is a sedative that was developed in the late 1950s and eventually marketed and prescribed in several countries to pregnant women to alleviate nausea in the late 1950s and early 1960s. The drug, however, caused severe birth defects in more than 10,000 children worldwide and was forced to withdraw from the international market. Further studies found that the S-optical isomer of thalidomide can inhibit neutrophil chemotaxis, produce anti-inflammatory activity, stimulate immune system activation, regulate immunity, anti-angiogenesis, and inhibit the adhesion of cancer cells to stroma, so as to change the microenvironment of the body, and achieve anti-tumor effect. Thalidomide has both anti-angiogenesis and antiemetic effects, and its combined use with TAS-102 may reduce the gastrointestinal reactions associated with TAS-102, while enhancing antitumor efficacy and reducing the side effects of chemotherapy, and its cost is significantly lower than that of bevacizumab, which has higher pharmacoeconomics and greater clinical research application value.