Study of Crenolanib for the Treatment of Patients With Advanced GIST With the D842-related Mutations and Deletions in the PDGFRA Gene

Crenolanib (CP-868,596) is an orally bioavailable, selective inhibitor of PDGFR receptor tyrosine kinase with IC50s of 0.4 ng/mL and 0.8 ng/mL for PDGFRα and PDGFRβ, respectively. In preclinical models of cell lines with the D842V mutation in the PDGFRA gene, crenolanib (CP-868,596) blocked phosphorylation of PDGFRα at nanomolar concentrations, suggesting that it may provide a clinical benefit to patients with D842V mutant GIST. In addition, crenolanib was also active in inhibiting phosphorylation of cell lines with two point mutations (double mutants) PDGFRA V561D + D842V and PDGFRA T674I + D842V.