OBJECTIVES: To identify evidence gaps in the literature on the burden of illness and treatment of adult primary immune thrombocytopenia (ITP) to support the launch of efgartigimod to treat this rare disease.
METHODS: A structured literature review was conducted from 1 July 2011 to 26 October 2021 in PubMed, Embase, and Cochrane regarding disease description, epidemiology, humanistic and economic burden, treatment guidelines, and treatment patterns. Desktop searches for health technology assessments (HTAs), competitor labels, and ongoing clinical trials were conducted.
RESULTS: Epidemiology of ITP varies and is likely inaccurate, as diagnosis is based on exclusion. No data are available on the proportion of patients in second- and third-line settings. Besides bleeding disorder, ITP presents other manifestations; current literature lacks robust analysis on other clinical burden. Recent data on health-related quality of life impairment are limited; prior studies used generic health-related quality of life instruments and were mostly of cross-sectional design, despite the disease’s chronic nature. Economic burden studies were United States focused and only evaluated healthcare resource utilization and direct cost during the first 12 months after diagnosis. Cost estimates of productivity loss were limited. Across different countries, treatment patterns were similar in the first-line but varied in second-line setting, and data beyond the second line are lacking. HTA decisions from different agencies recommended avatrombopag, eltrombopag, romiplostim, and fostamatinib to treat ITP, with varying restrictions. Economic evaluations of these therapies have been published or summarized in HTA decisions. Uncertainty about treatment response and a lack of effective treatment remain unmet needs for patients with ITP.
CONCLUSIONS: Various studies on ITP are identified in the literature; however, data are not all consistent or up-to-date. Several gaps have been identified that must be filled to support the launch of a new product in ITP, including epidemiology and humanistic and economic burden studies.
