Clinical Development of Regorafenib Combinations in Pediatric Rhabdomyosarcoma

Dieter Zopf, Principal Scientist at Bayer AG, Research and Development, Pharmaceuticals, Oncology, discusses the clinical development of regorafenib (Stivarga) combinations in pediatric rhabdomyosarcoma.

Physician experience and phase III data have shown that vincristine plus irinotecan is more effective than monotherapy approaches. In an ongoing trial investigating the optimal combination with regorafenib in pediatric rhabdomyosarcoma, researchers are using mode of action analysis in order to better understand whether there is a molecular basis for the combination of regorafenib plus irinotecan. Moreover, investigators are testing different schedules. The combination was tolerated in a mouse model, but toxicity has also been noted in the clinic.

The trial consists of 2 arms; one arm is giving the irinotecan plus vincristine together with regorafenib, and the other arm is giving chemotherapy followed by regorafenib one week later. The latter seems to be better tolerated, says Zopf. Researchers are hoping to see antitumor effects that will support subsequent clinical development of the combination.