Ipilimumab Doubled 5-Year Survival in Advanced Melanoma

March 4, 2015

Advanced melanoma patients who received front-line ipilimumab/dacarbazine had double the 5-year survival rate compared with those on dacarbazine alone.

Patients with advanced melanoma who received front-line treatment with ipilimumab/dacarbazine had double the 5-year survival rate compared with patients treated with dacarbazine alone, according to the results of a survival analysis published in the Journal of Clinical Oncology.

“This is the first milestone analysis of 5-year survival for patients with advanced melanoma who received ipilimumab in a randomized, controlled phase III trial, which was conducted to confirm prior reports of long-term survival in a proportion of patients from nonrandomized phase II studies,” wrote researchers led by Michele Maio, MD, PhD, Hospital of Siena, Siena, Italy. “Because the data are derived from a randomized, controlled phase III trial, they provide one of the strongest pieces of evidence for a long-term survival benefit with ipilimumab and also lend support to the results of prior analyses in nonrandomized studies.”

The survival analysis used data from the phase III CA184-024 trial that randomized patients with advanced melanoma to ipilimumab 10 mg/kg plus dacarbazine or placebo plus dacarbazine at weeks 1, 4, 7, and 10 followed by dacarbazine alone every 3 weeks. After 24 weeks of treatment, patients with stable disease or better could receive maintenance treatment every 12 weeks with either ipilimumab or placebo.

The median overall survival was 11.2 months for ipilimumab/dacarbazine compared with 9.1 months for placebo/dacarbazine (hazard ratio [HR] = 0.69; 95% CI, 0.57-0.84). At a follow-up of 5 years, 18.2% of patients assigned ipilimumab/dacarbazine were alive compared with 8.8% of patients assigned to the placebo/dacarbazine group (P = .0002).

“In this study, it is interesting to note that a plateau in the survival curve was observed in both groups, indicating that a proportion of patients have long-term survival independent of treatment,” the researchers wrote. “However, ipilimumab treatment results in approximately 10% more patients who achieve long-term survival.”

Of patients who survived 5 years, three patients (7.5%) in the ipilimumab/dacarbazine group achieved a complete response compared with no patients in the dacarbazine alone group. Additionally, 42.5% of patients assigned ipilimumab/dacarbazine had partial response compared with 35% in the dacarbazine alone group.

“This analysis demonstrates that a proportion of treatment-naive patients with advanced melanoma can achieve durable, long-term survival with ipilimumab therapy,” Maio and colleagues concluded.