Sustainability of Hematological and Clinical Benefits to HU Administration in the Prevention of Sickle-Cell Vaso-Occlusive Crises in Routine Practice

Hydroxyurea (HU) is approved in EU and USA for preventing vaso-occlusive crises (VOC) including acute chest syndromes (ACS) in adults, adolescents and children >=2 years with sickle-cell disease (SCD). Further to the double blinded, randomized controlled Multicenter Study of Hydroxyurea administration (MSH) which provided the first data on clinical efficacy of HU (Charache 1995), a few follow-up studies suggested that long-term use of HU resulted in significant clinical benefit on patient outcome. This was reflected by lower mortality rates in HU-treated patients compared to conventionally treated patients (Steinberg 2003 & 2010, Voskaridou 2010, Lê 2015). Sustained hematological and clinical response after several years of follow-up at maximal tolerated dose was further shown in subsequent studies, especially the LaSHS study (Voskaridou 2010). Based on these data, the ESCORT-HU (European Sickle Cell Disease COhoRT – HydroxyUrea) study was launched aiming in the establishment of the safety and the sustainability of hematological and clinical benefits to HU administration in the prevention of sickle-cell vaso-occlusive crises in routine practice. We hereby present preliminary results from a large cohort of patients enrolled in the study between January 2009 and June 2017. Conclusion: In preliminary results from ESCORT-HU in 147 patients treated with HU showed sustained hematological and clinical response while MTD was not targeted, with differences between adults and children which may be attributed in part to reduced compliance in the latter group. Abstract source