Sunitinib in metastatic renal cell carcinoma (mRCC): Preliminary assessment of toxicity in an expanded access trial with subpopulation analysis

Abstract

5010 Background: Sunitinib is an oral, multitargeted tyrosine kinase inhibitor of VEGFRs and PDGFRs, approved multinationally for advanced RCC. The primary aim of this international, open-label trial was to provide sunitinib to mRCC pts who failed =1 prior systemic therapy and were ineligible for other sunitinib trials or had no access to sunitinib before regulatory approval in their country. Methods: Eligibility criteria were minimized to broaden the enrolment population. Pts who were 18 yrs of age or older with histologically-confirmed mRCC received oral sunitinib 50 mg/day in 6-wk cycles (4 wks on Tx, 2 wks off). Physical exam, safety and concomitant meds were assessed every 4 wks. Results: As of Sept 1, 2006, 4,000 pts were enrolled from 181 sites in 36 countries; 2,158 pts (median age, 59 [19- 85]; male/female, 74%/26%) were included in this analysis. Baseline demographics included 106 pts (5%) with non-clear cell histology; 173 pts (8%) with brain mets; 158 pts (7%) with prior antiangiogenic Tx; and 288 pts (13%) with ECOG PS =2. Median Tx duration was 128 days (range 1- 2444) with interruptions in 17% of pts and dose reductions in 30%; 672 pts (31%) discontinued, of which 80 pts (12%) discontinued due to AEs. The median Tx duration was similar to the overall population regardless of age or site of metastatic disease at baseline (brain, bone, lung, liver, lymph nodes or other), but was longer in pts with ECOG PS 0/1 (154 days, range 1–2,444) than with ECOG PS =2 (83 days, range 1–449). The most common treatment-related AEs were diarrhea (39% any grade, 3% grade 3/4), fatigue (35%, 7%) and nausea (33%, 2%), the incidences of which were similar in pts regardless of age or site of baseline metastatic disease; overall, they occurred more frequently in pts with ECOG PS 0/1 vs. ECOG PS =2 (42% vs. 21%, 38% vs. 23%; and 34% vs. 25%, respectively), but differences in grade 3/4 severity were not observed. Median overall survival has not been reached; 19% of pts have died, the lowest incidence among pts with ECOG PS 0/1 (15%) and highest in pts with ECOG PS =2 (43%) and brain mets (34%). Conclusions: Preliminary observations suggest that sunitinib is associated with acceptable tolerability in an expanded access trial regardless of age or site of baseline metastatic disease. [Table: see text]