Perifosine (P), active as a single agent for renal cell carcinoma (RCC), now in phase I trials combined with tyrosine kinase inhibitors (TKI)

15622 Background: P is an oral alkylphosphocholine with effects on multiple pathways including Akt, MAPK and JNK. Akt/S6 is often activated in RCC and associated with resistance. In a phase I study of P, 3/6 RCC patients (pts) had stable disease (SD) lasting for 4, 6 and 14 months (m). RCC was further assessed in a broad phase 2 trial, and subsequently, two phase 1 trials combining P with TKIs have been initiated. This is an update of the phase II and first report of the phase I combination trials. Methods: From 3/05 to 5/06 241 pts, including 13 with RCC, were randomized to P, 50 mg daily or 1200 mg weekly. Subsequently the protocol was amended to P, 100 mg daily or 900 mg weekly, and enrollment continues. Pts with measurable disease who received at least 2 courses of P and at least one tumor measurement after initiation of P were considered evaluable for response using RECIST criteria. After demonstrating P activity in RCC, two phase 1 studies of P combined with either sorafenib (SOR) or sunitinib (SUT)...