Does eltrombopag lead to thrombotic events? A pharmacovigilance study of the FDA adverse event reporting system

Eltrombopag is an orally bioavailable drug developed as a second-line treatment for immune thrombocytopenia. However, there are limited reports on thrombotic events related to eltrombopag use. This study aimed to assess the relationship between eltrombopag and thrombotic events in a large population extracted from the Food and Drug Administration Adverse Event Reporting System (FAERS) database.

A total of 525 FAERS reports on thrombotic events associated with eltrombopag alone and 59 on those associated with the simultaneous use of eltrombopag and glucocorticoids, from Q1 2004 to Q3 2021, were included. Reports of thrombotic events were analysed using the following algorithms: reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker (MGPS). The time to onset and outcomes of thrombotic events between the two groups were also analysed.

A total of 525 reports of thrombotic events with eltrombopag were identified. Compared with eltrombopag alone, the concomitant use of eltrombopag and glucocorticoids was associated with a higher incidence of thrombotic events based on higher ROR (9.92, 95% two-sided CI 7.58-12.97 vs. 3.46, 95% two-sided CI 3.17-3.77), PRR (9.06, χ²  = 427.37 vs. 3.37, χ²  = 881.55), IC (3.18, 95% one-sided CI = 2.43 vs. 1.75, 95% one-sided CI = 1.6), and EBGM (9.06, 95% one-sided CI = 7.23, vs 3.36, 95% one-sided CI = 3.13).

Our findings support an association between thrombotic events and eltrombopag use. Moreover, concomitant use of eltrombopag and glucocorticoids appeared to result in an even higher incidence of thrombotic events.