US patients with advanced colorectal cancer have gained a new treatment option with the approval of Taiho Onology’s dual therapy Lonsurf (formerly TAS-102).

The pill - combining an anticancer drug called trifluridine, able to interfere with DNA function, with tipiracil hydrochloride, which maintains blood concentration of the former - has been green-lighted by the US Food and Drug Administration for patients whose disease has progressed despite treatment with standard therapies.

Approval came on the back of data from the Phase III RECOURSE trial, which showed a significant improvement in overall survival in patients taking Lonsurf compared to placebo, and a reduction in the risk of death of 32%.

On the downside, the drug did cause severe and life-threatening myelosuppression (a severe decrease in blood cell and platelet production), consisting of anaemia (18%), neutropenia (38%), thrombocytopenia (5%), and febrile neutropenia (3.8%), while one patient died from neutropenic infection. As such, the FDA has recommended that blood counts are recorded at certain stages of treatment. 

Colorectal cancer is the third most common type of cancer and is the second leading cause of cancer-related deaths in the US. While there have been significant advances in the detection and treatment of the disease, “there are many patients who still need additional options,” noted Richard Pazdur, director of the Office of Haematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research.

Lonsurf is already approved in Japan, and is also currently being reviewed by regulators in Europe.