To support this hypothesis, a phase II clinical trial in patients with recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC) showed that HNSCC patients with H-Ras mutations had a 55% objective response after receiving tipifarnib.335 Another phase II clinical trial in advanced refractory uroepithelial cancer patients with H-Ras mutations also found that response was observed in 5 out of the 12 evaluated patients after treatment with tipifarnib.336 For other tumours, FTIs in combination with other treatments can improve treatment efficacy to some degree. This evidence concerns the gene HRAS and neoplasm.