Ipilimumab: Phase III data

In a double-blind, placebo-controlled, international Phase III trial (Study 020) in 676 major histocompatibility complex class I A 0201 ( HLA-A 0201)-positive patients with previously-treated, unresectable stage III or IV metastatic melanoma, ipilimumab plus a gp100 peptide vaccine (n=403) met the primary endpoint of significantly improving OS vs. gp100 alone (n=136) (10 vs. 6.4 months, p=0.0004). Ipilimumab alone (n=137) also significantly improved OS, a secondary endpoint, vs. gp100 alone (10.1 months, p=0.0026). There was no significant difference in OS between ipilimumab groups (p=0.76).

Additionally, ipilimumab plus gp100 produced 1 complete response (CR), 22 partial responses (PR) and 58 cases of stable disease (SD) compared to 0 CRs, 2 PRs and 13 cases of SD for gp100 alone. Ipilimumab alone produced 2 CRs, 13 PRs and 24 cases of SD. Additionally, 44-46% and 22-24% of patients treated with ipilimumab were alive at 1 and 2 years, respectively, vs. 25% and 14% of patients treated with gp100 alone. In 32 patients who progressed following an initial response to the induction course of therapy, re-induction with ipilimumab produced a disease control rate of 65-75% vs. 0% for re-induction with gp100. ...