%) on sunitinib and 141 patients (39%) on IFN-α. Dose reductions occurred in 194 patients (52%) on sunitinib and 98 patients (27%) on IFN-α. Patients were treated until disease progression or withdrawal from the study. The primary efficacy endpoint was progression free survival (PFS). A planned interim analysis showed a statistically significant advantage for SUTENT over IFN-α, in this study, the median PFS for the sunitinib-treated group was 47.3 weeks compared with 22.0 weeks for the IFN-α-treated group; the hazard ratio was 0.415 (95% CI: 0.320-0.539, p-value <0.001). Other endpoints included objective response rate (ORR), overall survival (OS) and safety. Core radiology assessment was discontinued after the primary endpoint had been met. At the final analysis, the ORR as determined by the investigators' assessment was 46% (95% CI: 41 - 51) for the sunitinib arm and 12.0% (95% CI: 9 - 16) for the IFN-α arm (p<0.001).
Sunitinib treatment was associated with longer survival compared to IFN-α. The median OS was 114.6 weeks for the sunitinib arm (95% CI: 100.1 - 142.9 weeks) and 94.9 weeks for the IFN-α arm (95% CI: 77.7 - 117.0 weeks) with a hazard ratio of 0.821 (95% CI: 0.673 - 1.001; p=0.0510 by unstratified log-rank).
The overall PFS and OS, observed in the ITT population, as determined by the core radiology laboratory assessment, are summarized in the table below:
Summary of Efficacy Endpoints (ITT population)
Summary of Progression-Free Survival
Sunitinib
(N=375)
IFN-α
(N=375)
Subject did not progress or die [n (%)]
161 (42.9)
176 (46.9)
Subject observed to have progressed or died [n (%)]
214 (57.1)
199 (53.1)
PFS (weeks)
Quartile (95% CI)
25%
22.7 (18.0 to 34.0)
10.0 (7.3 to 10.3)
50%
48.3 (46.4 to 58.3)
22.1 (17.1 to 24.0)
75%
84.3 (72.9 to 95.1)
58.1 (45.6 to 82.1)
Unstratified Analysis
Hazard Ratio (sunitinib vs IFN-α)
0.5268
95% CI for Hazard Ratio
(0.4316 to 0.6430)
p-valuea
<0.0001
a From a 2-sided log-rank test.
Summary of Overall Survival
Sunitinib
(N = 375)
IFN-α
(N = 375)
Subject not known to have died [n (%)]
185 (49.3)
175 (46.7)
Subject observed to have died [n (%)]
190 (50.7)
200 (53.3)
OS (weeks)
Quartile (95% CI)
25%
56.6 (48.7 to 68.4)
41.7 (32.6 to 51.6)
50%
114.6 (100.1 to 142.9)
94.9 (77.7 to 117.0)
75%
NA (NA to NA)
NA (NA to NA)
Unstratified Analysis
Hazard Ratio (sunitinib vs IFN-α)
0.8209
95% CI for Hazard Ratio
(0.6730 to 1.0013)
p-value a
0.0510
a From a 2-sided log-rank test.
NA: Not Available (Not Reached)
Cytokine-Refractory metastatic renal cell carcinoma (MRCC).
A phase 2 study of sunitinib was conducted in patients who were refractory to prior cytokine therapy with interleukin-2 or IFN-α. Sixty
