A Phase II Trial of Saracatinib, an Inhibitor of src Kinases, in Previously-Treated Advanced Non–Small-Cell Lung Cancer: The Princess Margaret Hospital Phase II Consortium

BackgroundThe src family of kinases may play a role in the malignant phenotype through effects on migration, motility, adhesion and proliferation. The activity of saracatinib, an orally available inhibitor of src kinases, was evaluated in patients with advanced, platinum-pretreated NSCLC.Patients and MethodsEligible patients with advanced NSCLC of any histologic subtype and who had obtained a best response to prior platinum-based chemotherapy of at least stable disease received saracatanib 175 mg orally daily in a 28 day cycle. The primary end point was the proportion of patients progression-free after 4 cycles (16 weeks) of therapy; 8 such patients of 32 evaluable were required to deem the therapy active. Immunohistochemistry for src expression was performed on archival tissue from enrolled patients.ResultsThirty-seven patients received a median of 2 cycles (range, 1–14) each. Six of 31 evaluable patients were progression-free at 16 weeks. Two partial responses were observed, lasting 3.7 and 14.6 months; 1 responder had an EGFR exon 19 deletion. An additional 4 patients had stable disease for at least 4 cycles. The median progression-free and overall survival times were 1.8 and 7.6 months. No correlation between src protein expression and outcome was observed.ConclusionsThere may be a subset of saracatinib-responsive NSCLC that is currently molecularly undefined. Further studies of this agent in a population preselected for target mutations that potentially relevant to src pathways, such as EGFR, should be considered.