Management of metastatic melanoma in Texas: disparities in the utilization of immunotherapy following the regulatory approval of immune checkpoint inhibitors

Abstract

Background: The utilization of modern-immunotherapies, notably immune checkpoint inhibitors (ICIs), has increased markedly in patients with metastatic melanoma over the past decade and are recommended as standard treatment. Given their increasing adoption in routine care for melanoma, understanding patient access to immunotherapy and patterns of its use in Texas is crucial as it remains one of the few states without Medicaid expansion and with high rates of the uninsured population. The objectives of this study were to examine the trend in the utilization of immunotherapy and to determine factors associated with immunotherapy utilization among patients with metastatic melanoma in the era of ICIs in Texas.

Methods: A retrospective cohort study was conducted using the Texas Cancer Registry (TCR) database. The cohort comprised of adult (≥ 18 years) patients with metastatic melanoma diagnosed between June 2011 and December 2018. The trend in immunotherapy utilization was assessed by determining the proportion of patients receiving immunotherapy each year. The Average Annual Percent Change (AAPC) in immunotherapy utilization was assessed using joinpoint regression, while multivariable logistic regression was used to determine the association between patient characteristics and immunotherapy receipt.

Results: A total of 1,795 adult patients with metastatic melanoma were identified from the TCR. Immunotherapy utilization was higher among younger patients, those with no comorbidities, and patients with private insurance. Multivariable analysis showed that the likelihood of receipt of immunotherapy decreased with older age [(adjusted Odds Ratio (aOR), 0.92; 95% CI, 0.89- 0.93, p = 0.001], living in high poverty neighborhood (aOR, 0.52; 95% CI, 0.44 - 0.66, p < 0.0001), having Medicaid (aOR, 0.58; 95% CI, 0.44 - 0.73, p = 0.02), being uninsured (aOR, 0.49; 95% CI, 0.31 - 0.64, p = 0.01), and having comorbidities (CCI score 1: aOR, 0.48; 95% CI, 0.34 - 0.71, p = 0.003; CCI score ≥ 2: aOR, 0.32; 95% CI, 0.16 - 0.56, p < 0.0001).

Conclusions and relevance: This cohort study identified sociodemographic and socioeconomic disparities in access to immunotherapy in Texas, highlighting the need for policies such as Medicaid expansion that would increase equitable access to this innovative therapy.

Keywords: Access; Disparity; Immune Checkpoint Inhibitors; Immunotherapy; Melanoma; Texas; Utilization.

Fig. 1

Patient selection flowchart

Fig. 2

Temporal trends in immunotherapy utilization for patients with metastatic melanoma. A Overall immunotherapy utilization (B) Immunotherapy utilization by age category (C) Immunotherapy utilization by sex (D) Immunotherapy utilization by race (E) Immunotherapy utilization by insurance type (F) Immunotherapy utilization by comorbidity index. Figure 2f: There were no patients with 2 or more comorbidities in 2017–2018, and with comorbidity score of 1 in 2018

Fig. 3

Forest plot showing association between patient sociodemographic and clinical characteristics, and immunotherapy utilization. OR, odds ratio; CI, confidence interval; ref = reference. Time to treatment initiation means the time from diagnosis to receipt of the first treatment course