Comparing the safety and effectiveness of regorafenib versus TAS-102 for the treatment of patients with unresponsive metastatic colorectal cancer.

This study evaluated the effectiveness and safety of regorafenib (Stivarga) versus TAS-102 (Lonsurf; trifluridine-tipiracil) for the treatment of patients with unresponsive metastatic colorectal cancer (mCRC). The data showed that both treatments were safe and lead to similar survival outcomes for primary and secondary treatment of patients with unresponsive mCRC.

Colorectal cancer (CRC) is one of the most common types of cancer worldwide. Some patients do not report symptoms with the initial tumor. These patients are often only diagnosed when the cancer has spread to other areas (metastatic CRC). The standard treatment for these patients is chemotherapy combined with targeted therapy. A high number of patients with mCRC are unresponsive to standard treatments (refractory). Treatment options for refractory mCRC are limited.

Regorafenib is a targeted therapy. It targets cancer cells by stopping their growth and also stops the production of new blood vessels in tumors which often occurs in mCRC. This can help to slow the spread of cancer. Prior studies suggested that regorafenib improves treatment outcomes in older patients. TAS-102 is a combination of 2 chemotherapy drugs that stop cancer cells from dividing. This stops tumor growth and spread. Previous studies showed that TAS-102 was safe and improved survival in patients with mCRC. However, there are few studies evaluating the effectiveness and safety of regorafenib versus TAS-102 for the treatment of patients with unresponsive mCRC.

This study involved 140 patients with unresponsive mCRC. 64 patients received regorafenib and 76 patients received TAS-102 as the first treatment. After progression, 24 (37%) patients in the regorafenib group switched to second treatment with TAS-102. In the TAS-102 group, 29 (45%) patients switched to second treatment with regorafenib after progression.

8 (12.5%) patients achieved disease control (tumor does not grow or spread) in the regorafenib group compared to 17 (22.4%) patients in the TAS-102 group.

For the first treatment, the average survival without cancer progression was similar between the 2 groups – 2.5 months with regorafenib and 3 months with TAS-102. The average overall survival was also similar between the 2 groups- 6.8 months with regorafenib and 7.6 months with TAS-102.

For the second treatment, the average survival without cancer progression was 2.6 months in the regorafenib group who switched to second treatment with TAS-102, compared to 2 months in the TAS-102 group who switched to second treatment with regorafenib.

The average overall survival was 4.5 months in the regorafenib group who switched to second treatment with TAS-102, compared to 5.1 months in the TAS-102 group who switched to second treatment with regorafenib.

The most common side effects of regorafenib were fatigue, diarrhea and redness, swelling, and pain on the palm of the hand and sole of the foot. The most common side effects of TAS-102 were low white blood cell counts and diarrhea.

This study concluded that both treatments were safe and lead to similar survival outcomes for primary and secondary treatment of patients with unresponsive mCRC.

This study looked back in time at medical records. The sample size was small and only included patients from 3 institutions.