Comparison of the CELLEX™ and UVAR‐XTS™ closed‐system extracorporeal photopheresis devices in the treatment of chronic graft‐versus‐host disease

Extracorporeal Photopheresis (ECP) is a cellular immunotherapy frequently used for steroid‐refractory graft‐versus‐host disease (GVHD). Chronic GVHD (cGVHD), response to ECP is associated with survival benefit. The UVAR‐XTS^TM system and the more recently developed CELLEX^TM device (both Therakos^TM) are the mainstay for ECP‐delivery in the UK and US. No comparison of treatment outcomes has been reported. We retrospectively compared cGVHD response and steroid reduction and withdrawal in patients treated exclusively over 12 months with either the XTS (n = 51) or CELLEX (n = 50). Our hypothesis was that there would be no difference in clinical outcome or steroid changes in the 2 matched cohorts. We also compared infection incidence, infection‐related death (IRD), and treatment time. Significant clinical improvement and regular capacity to reduce or cease steroids was encountered in both cohorts; at 6 months of ECP 70% of cutaneous cGvHD patients had partial or complete responses and 85% of patients receiving steroids pre‐ECP had reduced dosage. In the XTS group we unexpectedly encountered both superior steroid reduction (86% dose at least halved vs. 61% for CELLEX, P = 0.01) and withdrawal (15 vs. 5 CELLEX, P = 0.01) and a trend for superior skin disease response in the CELLEX‐treated cohort at 3 months. No inter‐relationship was evident. Halving or greater reduction of steroid dose by 3 or 6 months was associated with reduced risk of IRD in the XTS cohort as was withdrawal at 6 months for the combined cohorts. By 6 months, XTS‐treated patients had experienced fewer antibiotic‐requiring infections (mean 1.9 vs. 2.8, P = 0.025). Origins for the disparities are unclear and warrant investigation.