Another phase Ib clinical trial has evaluated the efficacy of the combination of imatinib and ipilimumab in 12 metastatic/unresectable GIST patients [230], and found that only 1 gastric GIST patient with KIT/PDGFRA-WT genotype benefited from such combination therapy whom showed PR [230]. The gene discussed is PDGFRA; the disease is gastrointestinal stromal tumor.