LAUSR

e21006Background: IPI (anti-CTLA4) is approved for treatment of advanced MEL in adults, and more information on efficacy and safety of IPI in younger patients (pts) is needed. Methods: Pts from study CA184-178 (NCT01696045) age 12 to <18 yrs with previously treated or untreated, unresectable stage III or IV malignant MEL received up to 4 doses of IPI at 3 or 10 mg/kg Q3W. Key exclusion criteria were ocular MEL, active brain metastases, or autoimmune disease. Primary endpoints were 1-yr overall survival (OS) and safety. Results: From April 2013 to June 2016, 12 pts received either IPI 3 mg/kg (n=4) or 10 mg/kg (n=8); 2 did not meet study criteria and were not treated. For the 3 and 10 mg/kg groups, median age was 13 yrs and 15 yrs, 50% and 63% were male, 25% and 13% had elevated baseline lactate dehydrogenase, and 75% and 50% had prior systemic therapy, respectively. Median number of IPI doses received was 4.0 (range: 2–4) for 3 mg/kg and 3.0 (range: 1–4) for 10 mg/kg. At 1 yr, 3/4 pts on 3 mg/kg and 5/8 p...