BACKGROUND: The use of sunitinib at conventional doses (50 mg/d, 6-week cycles: 4 weeks of treatment, then 2 weeks of no treatment) in Asian patients with metastatic renal cell carcinoma (mRCC) is associated with high real-world toxicities.
PATIENTS AND METHODS: Patients with mRCC treated with sunitinib between 2005 and 2012 at 4 centers representing a near-national cohort (n = 160) in Singapore were evaluated. One hundred twenty-seven consecutive patients in 1 center were treated with a novel attenuated-dose sunitinib regimen (37.5 mg/d, 6-week cycle: 4 weeks of treatment, then 2 weeks of no treatment) with outcomes captured in a prospective registry. Efficacy and safety outcomes of these patients were compared against those who received sunitinib at conventional dosing (n = 33) at all 4 centers. Statistical modeling was adjusted for baseline prognostic criteria and therapy line where possible.
RESULTS: Overall survival from treatment initiation (OSinitiation), overall survival from the first documented metastasis (OStotal), and progression-free survival (PFS) were similar for patients who received first-line sunitinib for conventional relative to attenuated dose regimens (OSinitiation: 18.3 vs. 16.5 months, respectively; P = .54; OStotal: 27.4 vs. 21.8 months, respectively; P = .45; PFS: 6.7 vs. 7.9 months, respectively; P = .64), similar to real-world outcomes in Western studies. A marked lower rate of severe toxicities, dose delays, and reductions were observed with the attenuated dose regimen, with 75/127 (59%), rather than 28/33 (85%) for the conventional dose arm who experienced Grade ≥ 3 toxicities (P = .0088); 31/127 (24%) rather than 19/33 (58%) who experienced dose delays (P = .0004); and 44/127 (35%) rather than 23/33 (70%) who experienced dose reduction (P = .0005) during their course of treatment.
CONCLUSION: An attenuated dose regimen of sunitinib yielded comparable real-world efficacy outcomes, with considerable reduction in toxicities as documented in a prospective registry.
Written by:
Tan HS, Li H, Hong YW, Toh CK, Wong A, Lopes G, Tay MH, Chan A, Yao X, Tang T, Ng QS, Kanesvaran R, Chau NM, Tan MH. Are you the author?
Department of Medical Oncology, National Cancer Centre Singapore, Singapore; Department of Health Services Research, Singapore General Hospital, Singapore; Oncology Pharmacy, National Cancer Centre Singapore, Singapore; Department of Pharmacy, National University of Singapore, Singapore; Department of Haematology-Oncology, National University Health System, Singapore; Johns Hopkins International Medical Centre, Singapore; Onco-Care Cancer Centre, Gleneagles Hospital, Singapore; Tianjin Cancer Hospital, Tianjin Medical University, Tianjin, China; Institute of Bioengineering and Nanotechnology, Singapore.
Reference: Clin Genitourin Cancer. 2014 Nov 18. pii: S1558-7673(14)00255-9.
doi: 10.1016/j.clgc.2014.11.004
PubMed Abstract
PMID: 25541325