Dasatinib: an anti-tumour agent via Src inhibition

Dasatinib (BMS-354825, Sprycel®) is an oral, multitargeted inhibitor of receptor tyrosine kinases (RTKs), including BCR-ABL fusion protein, stem cell factor receptor (c-KIT), platelet-derived growth factor receptor (PDGFR), and Src family kinases (SFKs). Several early- and late-phase clinical trials for chronic myelogeneous leukaemia (CML) have demonstrated the direct inhibition of BCR-ABL fusion protein and SFKs, which led to dasatinib approval by the Food and Drug Administration (FDA) and the European Union for the treatment of imatinib-resistant or -intolerant CML, and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Phase III dose-optimization study was performed to compare different regimens, stating that dasatinib 100 mg once daily is now the recommended schedule for patients with chronic CML, and 140 mg once daily for patients with accelerated phase or myeloid or lymphoid blast phase CML, and for patients with Ph+ ALL until progression. Because of the myriad of critical roles of SFKs in biological processes, SFKs inhibition could induce numerous biological responses. Ongoing clinical trials evaluate dasatinib in the treatment of several solid tumours, including gastrointestinal stromal tumours (GIST), prostate cancer, malignant pleural mesothelioma, sarcomas, NSCLC, colorectal cancer, glioblastoma and other haematologic malignancies as multiple myeloma. Ongoing pre-clinical studies assess the therapeutic potential of dasatinib in other solid tumours, including melanoma, head and neck cancer, breast cancer and ovarian cancer. Dasatinib is generally well tolerated. Myelosuppression is the common adverse event which is, however, reversible by dose reduction, discontinuation, or interruption. Thrombocytopenia is more significant than neutropenia and associated to gastrointestinal bleeding and CNS haemorrhage. The most common non-haematologic adverse events include gastrointestinal symptoms (diarrhoea, nausea, vomiting, abdominal pain and anorexia), headache, peripheral edema, and pleural effusion. In respect of these encouraging studies investigating dasatinib in the treatment of patients with GIST, prostate cancer, multiple myeloma and sarcomas, ongoing phase III clinical trials warrant the drug evaluation as recommended agent for the treatment of these diseases, also in association with chemotherapy or other targeted therapies.