Use of Extracorporeal Photopheresis (ECP) in the Treatment of Patients with Cutaneous T-Cell Lymphoma (CTCL), 2010-2015

Introduction: Extracorporeal photopheresis (ECP) is an immunotherapeutic procedure approved in the US for the treatment of skin manifestations of cutaneous T-cell lymphoma (CTCL); in Europe, ECP is also used for the treatment of additional conditions such as graft versus host disease (GvHD), organ transplant rejection, and selected autoimmune diseases. Developments in immune system/cell biology and publications of real-world ECP data have advanced the understanding of the effects of ECP as a cell-based immunomodulator. The National Comprehensive Cancer Network (NCCN) CTCL Treatment Guidelines as well as the European Organization for Research and Treatment of Cancer (EORTC) recommend ECP as systemic therapy, which can be used in combination with interferon and/or a retinoid. The objective of this study was to analyze real-world use of ECP in the treatment of patients with CTCL in the US between 2010 and 2015.

Methods: A retrospective analysis was conducted using the Truven Health MarketScan^® Commercial and Medicare Supplemental claims databases (2010-2015). Patients with CTCL undergoing systemic treatment, with 9 months continuous enrollment (3 months prior to and 6 months after the initiation of systemic treatment), were included. Patient demographics and clinical characteristics by type of systemic therapy (ECP vs non-ECP) were evaluated, as well as most prevalent comorbid conditions. ECP use, frequency, and duration, as well as proportions of patients using ECP as mono- or combination therapy, were described. Propensity score matching and multivariate regression analyses were conducted to compare key outcomes such as length of stay (LOS), hospitalization cost, and total cost associated with use of ECP while controlling for covariates.

Results: Of the 2092 patients with CTCL who were receiving systemic treatment (12.6% of the total number of patients with CTCL [N=16,574]), 1106 patients were included who met the continuous enrollment criterion (mean age: 57.4 years; males: 57.1%). The top comorbid conditions were psoriasis (21.8%), organ transplant (12.2%), GvHD (7.5%), and scleroderma (2.5%). Of the 1106 eligible patients, 117 patients (10.6%) received ECP, with an average treatment duration of 13.6 months. ECP was used as monotherapy in 76 patients (65.0%) and combination in 41 patients (35%), mostly with interferon and/or a retinoid. Compared with non-ECP-treated patients (n=989), ECP-treated patients (n=117) had a significantly higher Charlson Comorbidity Index (CCI) score (2.6 vs 2.2, P <0.05), rate of organ transplant (49.6% vs 7.8%, P <0.05) and occurrence of GvHD (41.9% vs 3.4%, P <0.05). Generalized linear models (GLMs) were used to compare key outcomes (all-cause and CTCL-related LOS, hospitalization cost, and total cost) during the follow-up period, based on the pool of ECP-treated patients and propensity score matched non-ECP-treated patients. Results of GLMs indicated that ECP was associated with numerically lower all-cause and CTCL-related total LOS, all-cause hospitalization cost, and all-cause total cost while controlling for covariates.

Conclusions: Results from this US claims-based analysis of recent data demonstrated that ECP was used as a systemic treatment in 10.5% of patients with CTCL, with an average duration of 13.6 months. ECP was used twice as often as monotherapy compared with combination uses. CTCL patients treated with ECP appeared to have increased clinical complexity, with higher CCI scores, rates of organ transplant, and occurrence of GvHD. However, patients treated with ECP had lower all-cause LOS as well as numerically reduced hospitalization and total costs.