Sunitinib (SU) plus extended courses of irradiated allogeneic lymphocytes (IAL) for patients with metastatic renal cell carcinoma (RCC).

Abstract

464 Background: Treatment of patients with RCC using IAL from a haploidentical donor (sibling/parent), without prior conditioning of the recipient, induced tumor regressions in 3/13 patients with minimal toxicity (Strair J Clin Onc 2003:3785). Responses were not detected until after 2-3 courses, consistent with an immunologic mechanism. We hypothesize that combining the angiogenesis inhibitor SU with IAL will improve outcomes given the potential immune stimulatory benefit of VEGF inhibition and the benefit from preventing clinical progression prior to the development of an immune response in patients with rapid disease progression. Single agent SU has a median PFS of 11mos and response rate of 31%. Methods: Eligible pts with measurable metastatic clear cell RCC, no prior systemic therapy, adequate organ function, no CNS met, and a suitable donor (≥2/6 HLA A, B, DR match, CMV-, HIV-, HepB/C-) received SU 50mg/day in a 4 wk on/2wk off schedule with IAL administration commencing at the start of cycle number 2 of SU. IAL was given once every 8-16 weeks. The primary objective of the study is to determine the PFS of the combination of SU and IAL in 35 patients for 80% power to detect an increase in median PFS from 11 to 18 months. Results: A pre-planned futility analysis was performed. To date 9 pts (7M/2F), median age 63 (range 49-74) have been treated with 29 cycles of DLI. Median number of DLI/pt 2(1-7). 5 pts discontinued DLI due to disease progression, 4 due to loss of donor availability. Median time to disease progression was 41 weeks (range 12-180 weeks), with 4 pts on study for >80 weeks. Response rate (CR+PR): 44% (1/9 CR, 3/9 PR, 2/9 SD, 3/9 PD). DLI was well tolerated with G2 fever in 1pt and G1 fever in 5 pts as the only DLI related AEs. SU related AE lead to SU dose reduction in 8/9 pts. Conclusions: Co-administration of SU and IAL is feasible and safe with no significant IAL related toxicity. Further study accrual is required to determine if SU plus IAL is superior to single agent SU. Clinical trial information: NCT00853125.