The Cost-Effectiveness of Avatrombopag Versus Eltrombopag and Romiplostim in the Treatment of Patients with Immune Thrombocytopenia in the UK

BACKGROUND: Thrombopoietin receptor agonists-romiplostim, eltrombopag and avatrombopag-are commonly used as second-line treatments for immune thrombocytopenia (ITP). METHODS: A Markov model was developed to estimate the cost effectiveness of the three TPO-RAs in adults with insufficient response to previous treatment from the perspective of the UK National Health Service (NHS). The model considered the effects of bleeding events, concomitant ITP medications, rescue therapies and treatment related adverse events over a lifetime horizon. Model inputs for effectiveness were based on a network meta-analysis and other published literature on ITP management. Other model inputs included costs (e.g., drug acquisition and administration) and healthcare resource utilisation. RESULTS: Avatrombopag was associated with higher quality-adjusted life-years (QALYs) (10.979) than romiplostim (10.628) and eltrombopag (10.085), producing incremental QALYs of -0.351 and -0.894, respectively. Avatrombopag was associated with lower total costs (GBP £319,334) compared with romiplostim (GBP 406,361 [cost saving of GBP 87,027]) and higher total costs compared with eltrombopag (GBP 313,987 [incremental cost of GBP 5347]). Avatrombopag therefore dominated romiplostim (more effective and less expensive) and was cost-effective versus eltrombopag (incremental cost-effectiveness ratio of GBP 5982 per QALY). CONCLUSIONS: Avatrombopag is a cost-effective treatment compared with romiplostim and eltrombopag for the second-line treatment of adults with ITP from the perspective of the UK NHS.