A real-world analysis showed that adjuvant immunotherapy in patients with stage III melanoma improved survival, but that only approximately 33% of eligible patients received such adjuvant therapy after ipilimumab (Yervoy) was approved by the FDA for this indication.
Early data from this analysis, which were presented at the virtual 2020 AACR annual meeting, showed a trend toward improved survival in all patients with stage III melanoma 2 years after the approval of ipilimumab for this indication, and a significant improvement in survival in patients with stage IIIC melanoma who received this type of therapy.
The median overall survival was 32 months for patients who received adjuvant immunotherapy versus 28 months for those who did not receive this treatment.
“Patients with stage III melanoma tend to have poor prognosis even after curative intent surgery,” said lead investigator Justin T. Moyers, MD, Fellow, Hematology and Medical Oncology, Loma Linda University, CA.
“This first early analysis of the National Cancer Database in the era of adjuvant immune checkpoint inhibitor therapy shows that adjuvant immunotherapy in resected stage IIIC melanoma yielded a superior survival advantage. Based on our findings, immunotherapy after resected stage III melanoma appears to reveal a trend for real-world 24-month survival advantage compared with no therapy, supporting the role of adjuvant immunotherapy in the real-world setting.”
Gap in Access to Care
In addition, this study also found a gap in access to adjuvant immunotherapy.
“There was a trend towards a decrease in the receipt of immunotherapy for those with lower income and a lower high school graduation rate, but this was not statistically significant,” Dr Moyers said.
“The study was conducted from 2015 to 2016, the first year that an immune checkpoint inhibitor was approved for this indication. In the study, slightly more than one-third of patients did get an immune checkpoint inhibitor, and these patients did better than those who did not,” said AACR President Antoni Ribas, MD, PhD, FAACR, Director, Tumor Immunology Program, UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA.
“Patients covered by Medicare and those who had higher comorbidity scores were less likely to get adjuvant immunotherapy, and there was a trend toward those with lower income and lower rates of high school graduation being less likely to receive it,” Dr Ribas added.
“People with lower socioeconomic status don’t get treatment with proven benefit. Together, these data highlight the negative impact of socioeconomic background on access to state-of-the-art therapy in clinical trials and in the real world,” he emphasized.
Adjuvant Ipilimumab Therapy
Ipilimumab was approved by the FDA in 2015 as adjuvant therapy after surgical resection for stage III melanoma. The researchers wanted to study the uptake of adjuvant immunotherapy after this approval, so they used the National Cancer Database to identify patients with stage III melanoma who were diagnosed in 2015 or 2016. The investigators also analyzed survival data for patients diagnosed in 2015 who had surgery at the primary site of disease.
After the exclusion criteria were applied, the study sample included 8160 patients with stage III melanoma who underwent resection. The mean patient age was 63 years. A total of 27.7% of patients received adjuvant immunotherapy between 2015 and 2017. Patients who received treatment with adjuvant immunotherapy were younger and had fewer comorbidities than those who did not receive this treatment.
The database did not specify the type of immunotherapy patients received, but inferences can be made based on the chronology of the approval of therapies, Dr Moyers pointed out.
The median overall survival was not reached in either group, but the 24-month survival trended toward the use of adjuvant immunotherapy (83% vs 80%, respectively). With longer follow-up, Dr Moyers and colleagues expect to see the survival curves diverge even more.
Adjuvant immunotherapy was of significant survival benefit for patients with stage IIIC melanoma at 24 months; 70% of patients who received adjuvant immunotherapy were alive versus 59% (P <.01) of patients in the group that did not receive adjuvant immunotherapy.
In a separate analysis of treatment patterns of 8160 patients, 2260 (28%) received adjuvant immunotherapy after surgery. Increased comorbidity scores, lower income, lower rate of high school graduation, and Medicare as the primary payer were all associated with a lower likelihood of receiving adjuvant immunotherapy.
The limitations of the study include a lack of disease-specific survival and data on recurrence or progression-free survival. Some demographic data are derived from the zip codes of where the patients lived at the time of their diagnosis. It is also possible that some patients whose disease progressed after surgery received immunotherapy later.