A Phase Ii Study Of Everolimus (E) And Sorafenib (S) In Patients (Pts) With Metastatic Differentiated Thyroid Cancer Who Have Progressed On Sorafenib Alone

6072 Background: Recently, S became the first drug FDA-approved in 40 years to treat progressive, RAI-refractory thyroid cancer. S inhibits VEFR, PDGFR, Kit and RET. With S, patients achieve a median PFS of 10.8 months. We observed that pts may progress in some sites while maintaining stability in others. We hypothesized that progression on S may depend on increased activity of the AKT/MTOR pathway. Therefore we conducted a Phase II study to see if the addition of everolimus (E), an oral mTOR inhibitor, to S would have activity in pts who had progressed on S alone. Methods: 35 pts with evidence of progression by RECIST criteria on S were enrolled. Pts were started on a dose of S 200mg/d lower than their previously tolerated dose, combined with E 5mg/d. Pts were followed for toxicity; if tolerated, the dose of E and then S were incrementally increased to a maximum daily dose of S 800mg/day and E 10mg/day. The primary endpoint was progression-free survival (PFS). Response was evaluated by RECIST every 8 wee...