Safety of ipilimumab in patients (pts) with untreated, advanced melanoma alive beyond 2 years: Results from a phase III study.

8512 Background: Ipilimumab (IPI), a fully human monoclonal antibody, blocks cytotoxic T-lymphocyte antigen-4 to potentiate an antitumor T-cell response. In a phase 3 study (CA184-024) of previously untreated pts with stage III or IV melanoma, IPI + dacarbazine (DTIC) significantly improved overall survival (OS) vs. DTIC alone (Robert et al. NEJM 2011). We now report safety data of IPI in pts from this study alive > 2 yrs from study initiation. Methods: Pts with untreated advanced melanoma, were randomized to IPI (10 mg/kg) + DTIC (850 mg/m2) or placebo + DTIC (850 mg/m2) given at Wks 1, 4, 7, 10 followed by DTIC q 3 wks through Wk 22. Eligible pts (stable disease or better) received IPI or placebo q 12 wks as maintenance. In the population of subjects alive >2 yrs, the appearance of immune-related adverse events (irAEs) occurring after 2 yrs was evaluated. Within this group was a subset of subjects still receiving IPI dosing after 2 yrs; safety for these pts was evaluated to assess the impact of prolonge...