Therapy for Chronic ITP - the Patients' Perspective: US and Germany.
Authors: Matzdorff Axel C. , Arnold Gabriele , Hummler Simone S. , Grotzinger Kelly M. , Horblyuk Ruslan V. 
Published: October 2019

Abstract
Abstract 4451

Background
Chronic ITP is a rare disorder. Steroids are the usual 1st line therapy. Despite published guidelines there is considerable variation in 2nd and 3rd line therapies. Objective of this study was to compare therapies and patient-perceived treatment effects between the US and a European country (Germany).

Methods
Members of a US and a German patient support group >18 y with self-reported history of chronic ITP (>6 mo) were surveyed. A questionnaire was developed from literature review with clinician and patient input, and administered on-line. Demographics, patient histories, ITP therapy-related effects and side effects were recorded.

Results
712 subjects participated in both surveys (US 589, GER 123). Most were female (US 78%, GER 63%), and diagnosed with ITP for ≥5 years (US 59%, GER 70%). Many subjects had a minimum platelet count under 50.000/μl during the last year (US 68%, GER 66%), dry (US 79%, GER 72%) and wet purpura (US 46%, GER 64%). Corticosteroids were the most frequently reported therapy (USA 92%, GER 86%) followed by IVIg (USA 55%, GER 55%), splenectomy (USA 39%, GER 28%), rituximab (USA 36%, GER 22%, note: GER public health insurance does not reimburse rituximab). Patients experienced steroid treatment as particularly bothersome (both US and GER 90% report weight gain, moon face). For rituximab US patients reported most commonly fatigue, tiredness, weakness (47%), GER patients infusion reactions (55%). For splenectomy US patients reported most commonly scarring (67%), GER patients antibiotic use (38%). 56% of splenectomized GER pts. would not recommend this procedure to other patients.

Conclusions
Responding patients in the US and GER survey are both heavily pre-treated and report comparable side effects of those treatments. 1st line (steroid) and emergency treatment (IVIg) does not differ while 2nd/3rd line therapies vary. US patients are more likely to receive invasive (splenectomy) or even “off-label” therapies (rituximab) to have a chance of cure, presumably to reduce the financial burden of their disease. GER public health insurance covers all costs (except rituximab) and this might explain why GER patients are more willing to delay or even forego splenectomy. This implies that GER patients might be more inclined to try thrombopoietin receptor agonists before splenectomy. Future studies need to consider the effect of different health care systems on treatment decisions.

Disclosures:
Matzdorff: GlaxoSmithKline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AMGEN: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Baxter: Consultancy, Honoraria. Off Label Use: Rituximab for chronic ITP. Hummler:GlaxoSmithKline: Employment. Grotzinger:GlaxoSmithKline: Employment. Horblyuk:GlaxoSmithKline: Employment.