Dr. Raghav on Selecting Between TAS-102 and Regorafenib in CRC

Kanwal Raghav, MBBS, MD, an associate professor in the Department of Gastrointestinal Medical Oncology, of the Division of Cancer Medicine at The University of Texas MD Anderson Cancer Center, discusses the process for selecting between treatment with trifluridine and tipiracil (Lonsurf; TAS-102) vs regorafenib (Stivarga) in patients with colorectal cancer (CRC).

In September 2012, the FDA approved regorafenib to treat patients with metastatic CRC whose disease has progressed after prior therapy. Three years later, in September 2015, the regulatory agency gave the green light to TAS-102 for use in adult patients with metastatic CRC who previously received fluoropyrimidine-, oxaliplatin- , and irinotecan-based chemotherapy, an anti-VEGF biologic product, and an anti-EGFR monoclonal antibody, if RAS wild-type.

Although there is not a true rationale for selecting between the agents as the trials evaluating TAS-102 and regorafenib were done in similar patient populations, regorafenib tends to be used earlier than TAS-102 in the current setting, Raghav says. However, this does not account for other ongoing clinical trials examining the agents in combination regimens, Raghav adds.

Data evaluating the efficacy of TAS-102 in patients who were pretreated with regorafenib have read out, although regorafenib has not been evaluated in patients pretreated with TAS-102, according to Raghav. Moreover, most patients who are eligible for these agents have just concluded treatment with a large amount of 5-fluorouracil–based systemic chemotherapy regimens. Due to this, many patients already have cytopenia, Raghav notes.

Although regorafenib does have its own toxicities, they notably differ from those associated with TAS-102, Raghav explains. As TAS-102 can induce bone marrow suppression as a potential dose-limiting toxicity, a regorafenib bridging therapy can help bone marrow recover before moving on to treatment with TAS-102, Raghav concludes.