Dr. Grothey on Dosing Strategies With Regorafenib in CRC

Axel Grothey, MD, medical oncologist and director of Gastrointestinal Cancer Research at West Cancer Center and Research Institute, discusses dosing strategies with regorafenib (Stivarga) in colorectal cancer (CRC).

The dosing regimen of 160 mg of oral regorafenib given daily in a 3-weeks-on/1-week-off schedule was approved by the FDA in 2012, says Grothey. However, toxicity remains a concern with this strategy, Grothey explains. Because the main toxicities associated with regorafenib tend to appear within the first few weeks of treatment, the longer a patient can remain on treatment, the more tolerable the agent may become. As such, starting patients on 80 mg of regorafenib and dose escalating up to 160 mg may allow patients to tolerate regorafenib more easily, Grothey says.

Additionally, findings from the phase 2 ReDOS trial, demonstrated that this dose-escalation approach might be more effective than starting patients on 160 mg of regorafenib, says Grothey. However, many patients cannot tolerate regorafenib above 120 mg, Grothey adds. Although trying to maximize dosing to 160 mg is warranted, regorafenib is a cytostatic agent that provides additional benefit the longer a patient is treated, Grothey explains. Therefore, if a patient can sustain 120 mg of regorafenib for a prolonged period of time, maximizing the dose to 160 mg may not be necessary, concludes Grothey.