The Safety and Tolerability of the Novel Therakos Cellex Machine for Extracorporeal Photopheresis in the Treatment of Gvhd in Children

Extracorporeal photopheresis (ECP) is an established second line treatment option for graft versus host disease post hematopoietic progenitor cell transplant. At our center the Therakos Cellex has replaced the UVAR-XTS machine for ECP since 2009. We reviewed the records of 385 procedures using the Therakos Cellex. Nine patients underwent ECP for GVHD. The median age was 13.5 years (range 3.7 to 24) and weight was 49.2 kg (range 18.5-86.3). ECP was initiated at a median of 7.5 months (range 0.3-34.8) from the onset of GVHD. The mean duration per procedure was 106 minutes (range 60-205). Fifteen (3.9%) procedures were cancelled and 10 (2.6%) were delayed with central venous line (CVL) issues being the most frequent problem. Instillation of prophylactic tissue plasminogen activator (tPA) in the CVL lumens prior to a procedure was instituted 6 months before the end of study period, to reduce the incidence of CVL related occlusions and sluggish returns. With change in practice, fewer CVL related occlusions were observed (4.7% vs. 2.3%). There was one episode of CVL-associated thrombosis and one episode of delayed bleeding (mild and spontaneously resolved). There were four episodes of viral reactivation, 4 CVL-associated infections (1142 catheter days) and 1 episode of systemic inflammatory response syndrome. No patient experienced hypotension that required medical intervention. Although no additional adverse events were noted, there was considerable blood exposure in the smallest patients because of the need for machine blood prime. The Therakos Cellex appears to be safe and well-tolerated in 385 procedures performed in our institution. This is the first report regarding the safety and tolerability of this device for ECP in children and young adults.