A University of Chicago Consortium Phase II Trial of SB-715992 in Advanced Renal Cell Cancer

Background Advanced renal cell cancer (RCC) continues to have a poor overall prognosis despite new FDA-approved therapies. Although taxane-based therapies are generally ineffective in RCC, research into the role of the von Hippel–Lindau protein has shown an association with microtubule dynamics. Mitotic kinesins are a class of molecular motors that also interact with microtubules and are required for proper mitotic function. SB-715992 is a new agent that inhibits the function of a mitotic kinesin known as kinesin spindle protein and leads to cell death. Patients and Methods Twenty patients with previously treated advanced RCC were enrolled on this phase II trial of SB-715992, with response rate as a primary endpoint. Results No patients responded with complete or partial remission. Six patients had stable disease, and 1 patient continues on therapy after 12 cycles. Common toxicities included anemia (80%), elevated creatinine (70%), lymphopenia (45%), fatigue (50%), hyperglycemia (50%), and dyspnea (45%). Reported grade 3/4 toxicities included dyspnea, fatigue, neutropenia with skin infection, dizziness, hyperuricemia, and hypertension. Conclusion This dose and schedule of SB-715992 does not appear to have a significant cytotoxic effect for patients with previously treated advanced RCC.