Sunitinib treatment for patients with advanced clear-cell renal-cell carcinoma after progression on sorafenib.
BACKGROUND
Sorafenib and sunitinib are tyrosine kinase inhibitors with largely overlapping specificities, approved for the treatment of metastatic renal-cell carcinoma (RCC). It was unclear whether the similarities of the two drugs would lead to complete cross-resistance, or whether sequential application would be efficacious.


METHODS
Patients with metastatic RCC and progression on sorafenib treatment were treated with repeated cycles of sunitinib, 50 mg for 4 weeks, followed by a 2-week break. Response (Response Evaluation Criteria in Solid Tumors, RECIST) was assessed every second cycle.


RESULTS
A total of 22 patients with progression on sorafenib were accrued. Initially, sorafenib treatment was efficacious in all patients, with 7 showing partial response (PR) and 15 stable disease (SD), and subsequent disease progression. With 4 PRs (18%) and 12 SD (55%) a disease control rate of 73% was achieved. The median progression-free survival (PFS) on sunitinib was 21.5 weeks; median overall survival (OS) was not reached. Estimated 1-year PFS and OS were 31 and 60%, respectively. There was no apparent relationship between response to sorafenib and outcome on sunitinib.


CONCLUSIONS
In our cohort of patients with RCC and progression after initial efficacy of sorafenib, the efficacy data of second-line sunitinib were close to published results of first-line treatment, suggesting limited clinically relevant cross-resistance.
Zimmermann
Kaja
K
Department of Medicine III (Hematology, Oncology and Transfusion Medicine), Charité, Campus Benjamin Franklin, Berlin, Germany. kaja.zimmermann@charite.de
Schmittel
Alexander
A
Steiner
Ursula
U
Asemissen
Anne Marie
AM
Knoedler
Maren
M
Thiel
Eckhard
E
Miller
Kurt
K
Keilholz
Ulrich
U