Dr. Tanios Bekaii-Saab on Sequencing Questions in mCRC

Tanios Bekaii-Saab, MD, a professor of Medicine at Mayo Clinic, discusses sequencing regorafenib (Stivarga) and TAS-102 (Lonsurf) in metastatic colorectal cancer (mCRC).

The two agents were tested in very similar settings, but they have never been compared head to head.

Regorafenib was compared with placebo in a large study, where it showed superiority to placebo in all parameters. TAS-102 was also compared with placebo and also showed an improvement in all efficacy parameters.

However there is little guidance regarding sequencing these two agents, says Bekaii-Saab.

In the RECOURSE study, which looked TAS-102 versus placebo, about 20% of the patients were already exposed to regorafenib. Those patients seemed to do as well those who were not previously exposed to regorafenib.

Based on that it is clear that if regorafenib is given first, TAS-102 preserves its activity. Unfortunately, it is unclear if that is the case with regorafenib, says Bekaii-Saab.

There are some hints about where regorafenib work best, he says. The CONCUR study—which is an Asian study—looked at patients in which, of about 40% to 50% of them, did not have exposure to anti-VEGF or anti-EGFR therapies. What this study historically suggests compared with CORRECT—which was the initial regorafenib study—is that the deltas between regorafenib and placebo are bigger, says Bekaii-Saab.

This means that regorafenib seems to confirm a further benefit if moved up the line, he says.