Ipilimumab in patients with melanoma brain metastases, a single-center experience in an expanded access program.

Abstract

e19027 Background: patients (pts) diagnosed with melanoma brain metastases (MBM) have a poor prognosis with conventional treatment options. Ipilimumab (IPI) is a CTLA-4 blocking monoclonal antibody with established activity in patients (pts) with pretreated advanced melanoma. Methods: observational study on the clinical outcome of melanoma pts with a prior diagnosis of MBM among pts treated with IPI (3 mg/kg q3wks x4, allowing for retreatment after a PFS of >24 wks) in an expanded access program at a single center. Results: among the 50 pts who initiated IPI treatment between April 2010 and May 2011, 16 pts had been diagnosed with MBM. Only 1 pt had a solitary MBM, all other pts had > 3 MBM. Baseline characteristics for pts with- and without MBM: M/F 8/8 vs. 20/14; mAge 44- vs. 50y; BRAF V600-mut/wt 10/6 vs 19/15; stage IV-M1c/-a&b 16/0 vs 31/3; WHO-PS 0-1/2 9/7 vs 30/4; LDH >ULN 10/6 vs 23/11; CRP >ULN 10/6 vs 20/14; ALC<1000/mm³ 3/13 vs 11/23. All pts were pretreated with DTIC; 3 pts with stereotactic (stRT), 7 pts with WBRT, and 2 pts with WBRT followed by a stRT boost; 4 pts had no prior therapy for MBM. 7/16 pts with- vs. 24/34 pts without MBM completed IPI-treatment; 3/16 pts with- vs 8/34 pts without MBM had IPI-retreatment. Adverse events were managed following established guidelines and were generally mild/reversible (<20% pts gr3-, none gr4/5) and similar in pts with- or without MBM at the exception of symptomatic radiation necrosis of the brain (RNB) observed in 3 pts (1x gr2, 2x gr3). Following surgery (1pt), and corticotherapy (3pts) all pts recovered their RNB related symptoms. Best objective tumor response (BOR) by RECIST outside the CNS in pts with- vs without MBM was 1PR vs. 1CR/2PR/4SD; according to the immune-related response criteria: 3PR vs. 1CR/2PR/7SD. After a median follow-up of 18 months, 32 pts have died (11/16 with- vs. 21/34 without MBM). The probability for OS was not significantly different for pts with- or without MBM (HR .76 [95%CI 0.36-1.59]; p: .475 by Log-Rank test). Conclusions: in our single-center experience with IPI for pts with advanced melanoma treated in an EAP, the probability for OS for patients with a prior history of MBM was not significantly different from pts without a prior history of MBM.