Inline extracorporeal photopheresis: evaluation of cell collection efficiency

Abstract

BACKGROUND Extracorporeal photopheresis (ECP) therapy has proved to be an effective and safe treatment for graft‐versus‐host‐disease (GvHD), an important complication after hematopoietic stem cell transplantation. In 2016, we acquired Therakos CellEx, a dedicated inline ECP device to accomplish a significant increase in ECP activity. In literature, we found few data reporting CellEx performance evaluated in terms of collection efficiency to qualify the device. Hence, we decided to collect and analyze our data in order to build a reference in terms of expected results of the procedure. Here we report our data of ECP performed using CellEx in a 12‐month period focusing on collection efficiency assessment, as well as procedural and apheretic product characteristics. STUDY DESIGN AND METHODS We collected data of patients undergoing ECP from April 2018 to March 2019 using CellEx in order to evaluate collection efficiency. RESULTS Between April 2018 and March 2019 we treated 28 adult patients affected by GvHD performing 319 ECP using CellEx. CellEx mononuclear cell product was characterized by high mononuclear cell percentage and low percentage of granulocytes, resulting particularly suitable for ECP treatments. Median collection efficiency for total nucleated cells and for mononuclear cells was 31.2% and 62.3%, respectively. CONCLUSION Collection efficiency of CellEx was comparable to that usually obtained by cell separators designed for cell collection and was comparable to that of offline systems. Our results provide a detailed performance evaluation for inline ECP system users.

Pilot study of a new online extracorporeal photopheresis system in patients with steroid refractory or dependent chronic graft vs host disease

“…In the Amicus ECP system, the procedure duration and collected cell yields were comparable to the online Therakos CELLEX system but with higher MNC purity, similar to offline ECP with the Spectra Optia (Table 5). 8 The median MNC collection efficiency (CE1) of the Amicus ECP system was 56%, which is higher than the 42% median MNC CE1 reported by Cid et al for cGVHD patients collected using the COBE Spectra/Spectra Optia leukapheresis devices for offline ECP and similar to the values reported by Brosig et al and Piccirillo et al for these same devices and the Therakos CELLEX in broader ECP patient populations (50‐60%) 12‐14 …”

“…8 The median MNC collection efficiency (CE1) of the Amicus ECP system was 56%, which is higher than the 42% median MNC CE1 reported by Cid et al for cGVHD patients collected using the COBE Spectra/Spectra Optia leukapheresis devices for offline ECP and similar to the values reported by Brosig et al and Piccirillo et al for these same devices and the Therakos CELLEX in broader ECP patient populations (50-60%). [12][13][14] The hematocrit and composition of the collected cells are important factors for consistent photoactivation in terms of UVA exposure and photoactivation time. In the Amicus ECP system, the median hematocrit of the collected cells was 2% (as targeted by the system) with a narrow hematocrit range even over a broad range of patient cell counts.…”

Inline and offline extracorporeal photopheresis: Device performance, cell yields and clinical response

“…This experience was published in a paper focusing on leukapheretic product characteristics and cell collection efficiency. 9 Contemporaneous availability of both offline and inline systems allowed us to compare procedures and cell product features to highlight key process and performance characteristics of the two different technical approaches.…”

“…Since the second half of 2016, we began to use also the inline system CellEx (Mallinckrodt Pharmaceuticals, formerly Therakos Inc., West Chester, Pennsylvania). This experience was published in a paper focusing on leukapheretic product characteristics and cell collection efficiency 9 …”

Bacterial contamination rates in extracorporeal photopheresis

“…Bacteria could distribute freely in plasma, or they could sediment together with red blood cells and platelets. Intermittent flow apheresis using the Latham bowl technique as in Therakos devices, in contrast to the technique used within the Amicus, collects less selected cell suspensions in general, though there are exceptions to this . Inferior collection ability of inline ECP could translate to a reduced bacterial enrichment.…”