Among patients with stage IIIC disease, the 2-year survival rate was 70% in those who received immunotherapy and 59% in those who did not (P < .01). The median overall survival in this group was 32.8 months with immunotherapy and 28 months without it (P < .01).
Among patients with stage IIIA disease, the 2-year survival rate was 94% with immunotherapy and 91% without it (P = .03).
There was a trend toward a 2-year survival benefit with immunotherapy in patients with stage IIIB disease and in all 4,094 stage III patients, but the differences were not significant. The 2-year survival rate was 84% with immunotherapy and 81% without it among patients with stage IIIB disease (P = .35). The survival rates were 83% and 80%, respectively, in all stage III patients (P = .051).
This was an early analysis, noted investigatorof Loma Linda (Calif.) University. Ipilimumab was approved as adjuvant therapy for stage III melanoma patients in 2015, the year patients from this analysis were diagnosed.
“There’s really only 2 full years of survival data,” Dr. Moyers said. “I think given time, we will see a benefit amongst all the substages.”
In the meantime, “I would definitely not use this data to say whether or not [immunotherapy] should be given,” Dr. Moyers said.
The researchers were just using the database – which captures 52% of U.S. melanoma cases – to see if “real-world data mimics the clinical trial data,” Dr. Moyers said.
Overall, the findings support “adjuvant immunotherapy in the real-world setting,” he said.
The researchers also looked at treatment patterns in 2015-2016 across 8,160 patients with stage III melanoma, 4,094 of whom were included in the aforementioned survival analysis. There were 2,260 patients (27.7%) who received immunotherapy after surgery during that time period.
Uptake of adjuvant immunotherapy “was low to start, but those patients did better than ones who did not get” it, said AACR presidentof the University of California, Los Angeles, who was not involved in the study.
Immunotherapy recipients were younger, on average (54.8 years vs. 62.4 years). Patients with Charlson comorbidity scores above zero and those on Medicare were less likely to receive immunotherapy (18.4% Medicare vs. over 30% with other payers). There also were trends of decreased use with lower income and lower high school graduation rates.
The finding “highlights the negative impact of socioeconomic [factors] on access to proven therapy,” Dr. Ribas said.
As for low use among Medicare patients, uptake of new treatments, in general, “seems to be faster with private insurance,” he noted.
The study excluded patients who received systemic therapies other than immunotherapy, as well as those who received immunotherapy before surgery. Among study limitations, the specific immunotherapies patients received was unknown.
There was no external funding for this study. Dr. Moyers reported travel compensation from Astellas Pharmaceuticals in 2018. Dr. Ribas disclosed relationships with Amgen, Chugai, Merck, Sanofi, Tango, Arcus, Bioncotech, Compugen, CytomX, FLX Bio, ImaginAb, Isoplexis, Merus, Rgenix, and PACT.
SOURCE: Moyers J et al. AACR 2020,