This study aims to report the clinical effectiveness and cost-effectiveness of Thrombopoietin (TPO) receptor agonist for the treatment of adults with spontaneous Immune Thrombocytopenic Purpura (ITP) in Taiwan.

In the clinical effectiveness evaluation section, particularly for the TPO receptor agonist, we searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials to identify all randomized trials in chronic ITP. In the economic evaluation section, we performed a long-term cost-effectiveness analysis using a Markov model to evaluate the value of TPO receptor agonist to achieve durable platelet response for chronic ITP patients.

Our findings revealed that the National Health Insurance (NHI) in Taiwan covers TPO receptor agonists romiplostim and eltrombopag, which have also been recommended by the Pharmaceutical Benefits Advisory Committee (PBAC) of Australia and the National Institute for Health and Care Excellence (NICE) in the United Kingdom. In addition, a systematic review and meta-analysis combining six trials were included to assess the current evidence on the role of TPO receptor agonist in chronic ITP. The primary outcome of randomized controlled trials (RCTs) showed an improving trend in significant bleeding events; however there was not any significant difference between the TPO receptor agonists group and the control group (placebo). The gain in life years and quality-adjusted life-years (QALYs) from introducing long-term use of TPO receptor agonists over current clinical practice were 1.52 years and 1.44 QALYs, respectively. Most of the sensitivity analysis results show that the ICER values were greater than 3GDP per capita in Taiwan.

Compared to placebo, and despite a significantly increased platelet response, there was no evidence to demonstrate that TPO receptor agonists did improve significant bleeding events in chronic ITP. The effect on overall survival awaits further analysis. Although long-term studies are lacking, current data demonstrated that adverse effects of TPO receptor agonists were similar to that of placebo.