PF718 THE ECONOMIC AND HUMANISTIC BURDEN OF GRAFT‐VERSUS‐HOST DISEASE (GVHD) IN PEDIATRIC PATIENTS: A SYSTEMATIC LITERATURE REVIEW (SLR)

Background: Children with hematologic malignancies and/or disorders may be candidates for allogeneic hematopoietic stem cell transplants (allo‐HSCT), a potentially curative treatment, however, this treatment carries a risk of serious complications. Approximately 39–59% of allo‐HSCT patients develop grades B‐D acute GVHD, a serious and life‐threatening complication. Aims: The objective was to conduct a comprehensive review of published evidence regarding the economic and humanistic burden of GVHD in a pediatric population. Methods: A SLR was conducted on 12‐Jan‐2019 following the Preferred Reporting Item for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines using the Population, Intervention & Comparators, Outcomes and Study Design (PICOS) criteria to identify relevant studies published between 2009–2019 in key biomedical literature databases: EMBASE, MEDLINE and Cochrane. A total of 1172 records from the economic search and 2577 from the quality of life (QOL) search underwent subsequent screening. Two independent reviewers screened all citations using PICOS‐based criteria. Discrepancies between reviewers were resolved through roundtable discussion. Congresses including ASCO, ASH, BMT, EBMT, EHA, ESMO and ISPOR were reviewed for relevant material published between 2015‐2019. Results: A total of 15 QOL and 7 economic studies satisfied inclusion criteria. In QOL, 7 studies were US‐based, 4 were EU‐based and PedsQL was the most frequently reported scale (8 studies) followed by SF‐36, FACT‐BMT, CHRI (2 each), among others. Large deteriorations in post‐allo‐HSCT pediatric patients with GVHD vs. without GVHD were shown in the Generic PedsQL, PedsQL Transplantation module, PedsQL Physical Functioning Scores at 2 years, SF‐36 Physical and Mental Health components, CHRI global HRQOL and FACT‐BMT total score. One survey in thalassemia patients found QOL declines associated with GVHD at least 20 years after transplantation demonstrating potential long‐term implications of GVHD, particularly relevant in pediatric patients with longer life expectancies. This decrement was statistically significant with FACT‐BMT total scores of 116 vs. 125 (p = 0.0067) for thalassemia pediatric patients with GVHD vs. without GVHD, respectively. One study using the Peds QL 4.0 Generic Scale found that the 2‐year score of pediatric patients who underwent allo‐HSCT with chronic GVHD vs. those without chronic GVHD was 42.72 vs. 83.96, respectively, further demonstrating the long‐term humanistic burden of GVHD. Symptoms of GVHD in pediatric populations included psychological problems (up to 65% of teenagers as described in one study), self‐reported pain, itchiness, dryness, sensitivity, shortness of breath, depression, loss of weight, loss of energy, fever, among others. Of the 7 economic studies, 4 were US‐based cost studies, one cost study was based in France, one was a decision analysis and another a cost‐effectiveness analysis. Across 4 US‐based cost studies, pediatric allo‐HSCT patients with acute GVHD were found to have longer hospitalizations (incremental 17.9–45.4 days, varies by study) and increased costs (incremental $114,698‐$224,000). An increased cost associated with acute GVHD was also seen in the France‐based study of acute lymphoblastic pediatric patients. Summary/Conclusion: GVHD is associated with substantial increased costs of care in pediatric transplant patients. QOL is poorer in transplanted patients with GVHD than in those without. The combined economic and QOL burden of GVHD identify an ongoing need to be addressed by treatments in development.