Anti-tumor efficacy of the novel KIT inhibitor IDRX-42 (formerly M4205) in patient- and cell line-derived xenograft models of gastrointestinal stromal tumor (GIST).

IDRX-42 showed significant antitumor activity in patient- and cell line-derived GIST xenograft models. The novel kinase inhibitor induced volumetric responses, decreased mitotic activity and had antiproliferative effects. In models with KIT exon 13 mutation IDRX-42 induced characteristic myxoid degeneration.