Response to Extracorporeal Photopheresis in Patients with Cutaneous T-Cell Lymphoma: A Retrospective Medical Chart Review
Authors: Girardi Michael , Johnson Amy G , Carlson Kacie , Huang Xingyue , Corman Shelby , Edmundson Patrick , Kale Hrishikesh P , Rusibamayila Nifasha , Foss Francine M. 
Published: November 2021

Abstract
INTRODUCTION
Extracorporeal photopheresis (ECP) is an immunomodulatory therapy that has been used in the treatment of cutaneous T-cell lymphoma (CTCL) for over 30 years. Clinical trials of newer agents for the treatment of CTCL have shown response rates of approximately 30% in heterogeneous patient populations. The objective of this study was to assess the effectiveness of ECP in the treatment of CTCL patients in real-world clinical practice.
METHODS
This is an interim analysis of a retrospective medical chart review study conducted at clinical sites in the United States, in which treating physicians were responsible for patient selection and data collection via structured case report forms. Patients with a confirmed diagnosis of CTCL who initiated ECP between January 1, 2017 and February 28, 2019 were included in the study. In addition, patients must have initiated ECP at age ≥18 years with no ECP treatment received within the year prior to data collection, have received at least 3 months of ECP treatment, and have response data available in the patient chart. Data collected included patient demographics, clinical characteristics, and treatments received prior to and concomitantly with ECP. Clinical outcomes were collected every 3 months during treatment for up to 18 months, and included the body surface area (BSA) affected, appearance of new skin lesions, and the physician-rated Clinical Global Impression-Improvement (CGI-I) scores. Response to ECP was defined as &gt;50% reduction in BSA affected at any point during the follow-up period, consisting of the time from ECP initiation through the time of data collection. Data analysis was descriptive in nature.
RESULTS
Four clinical sites participated in the study and enrolled a total of 26 patients for the interim analysis. Patients were predominantly female (53.8%) and White (88.5%). Mean age at CTCL diagnosis was 68.4 years, and the majority patients were diagnosed with Sézary syndrome (57.5%) or mycosis fungoides (30.8%). Nearly half of patients (46.1%) had stage IV disease at diagnosis (IVA, 26.9%; IVB, 19.2%) and half of patients (50.0%) had lymph node involvement at diagnosis. Median BSA involvement with plaques/patches at diagnosis was 80% (interquartile range [IQR], 20% to 90%). Six patients (23.1%) achieved &gt;50% reduction in BSA affected, and among those, median time to response was 6.0 months (IQR, 2.9 to 15.0 months). New skin lesions appeared in 5 patients (19.2%). Among those with available data, the percentage of patients rated as minimally improved, much improved, or very much improved on the CGI-I was 57.7% at 3 months (N=26), 50.0% at 6 months (N=18), and 60.0% at 9 months (N=15) after ECP initiation.
CONCLUSIONS
This retrospective observational study describes patient characteristics and clinical outcomes among CTCL-diagnosed patients initiating therapy with ECP. Despite the population treated with ECP in real-world practice being older and having more advanced-stage disease compared to recent clinical trials, response rate was comparable.

Disclosures
Girardi: Transimmune: Patents & Royalties: Inventor/IP; Helsinn: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Research Funding; Soligenix: Research Funding; Mallinckrodt Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Stradefy Biosciences Inc: Patents & Royalties: Inventor/IP; Actelion: Membership on an entity's Board of Directors or advisory committees, Research Funding. Huang: Mallinckrodt Pharmaceuticals: Current Employment. Corman: Mallinckrodt Pharmaceuticals: Consultancy. Edmundson: Mallinckrodt Pharmaceuticals: Consultancy. Kale: Mallinckrodt Pharmaceuticals: Consultancy. Rusibamayila: Mallinckrodt Pharmaceuticals: Consultancy. Foss: Kura: Honoraria; Daiichi Sankyo: Honoraria; Seattle Genetics: Honoraria, Speakers Bureau; Acrotech: Honoraria, Speakers Bureau; Mallinckrodt: Honoraria; Kyowa: Honoraria.