Patients with metastatic melanoma treated with ipilimumab or ipilimumab plus nivolumab have a significantly higher likelihood of being hospitalized and higher ER visits compared with patients treated with other immunotherapies, according to a study (Abstract 137) presented at the American Society of Clinical Oncology (ASCO)-SITC Clinical Immuno-Oncology Symposium (February 28 – March 2, 2019; San Francisco, CA).
A wealth of research has shown the survival benefits of immunotherapies compared with chemotherapy for patients with metastatic melanoma. However, data is limited concerning the comparative health resource utilization among different immunotherapies.
Frank Xiaoqing Liu, PhD, Merck & Co, and colleagues designed a study to examine the real-world health resource utilization across PD-1 inhibitors (pembrolizumab or nivolumab), a CTLA-4 inhibitor (ipilimumab), and a combination of immunotherapies (ipilimumab plus nivolumab). The retrospective observational study selected adult patients with at least two US payer claims for metastatic melanoma and at least one claim for metastasis between January 2012 and June 2017. All patients had pharmacy and medical claims as well as at least 6 months pre-index enrollment.
Health resource utilization was calculated per patient per month and by percentages across PD-1 therapy, ipilimumab, and ipilimumab plus nivolumab from index date until the first occurrence of change in regimen, end of continuous enrollment, or end of study period.
Researchers noted that on average, patients in the PD-1 cohort (n = 255) were older than those in the ipilimumab cohort (n = 555) and the ipilimumab plus nivolumab cohort (n = 88). Patients in the PD-1 cohort also exhibited less brain metastases than those in the other two cohorts.
During first-line therapy, fewer patients in the PD-1 cohort had any hospitalization (25.9% vs 39.8% and 45.5%, respectively), fewer hospital admissions per patient per month (mean, 0.06 vs 0.10 and 0.14, respectively), and fewer ER visits per patient per month (mean, 0.09 vs 0.13 and 0.18, respectively). Thirty-day hospitalization readmissions (13.7% vs 19.1% and 18.2%, respectively) and ER visits (40.0% vs 47.0% and 50.0%, respectively) were lower for patients in the PD-1 cohort, though not statistically significant.
Additionally, Dr Liu and colleagues noted that after adjusting for baseline characteristics, patients treated with ipilimumab and ipilimumab plus nivolumab were more likely to have a hospitalization compared with patients treated with PD-1 therapy.
While these data suggest that first-line treatment of metastatic melanoma with PD-1 therapy results in less health care resource utilization, researchers concluded that further studies are warranted to confirm these findings.—Zachary Bessette