Risk of thromboembolism with thrombopoietin receptor agonists in adult patients with thrombocytopenia: Systematic review and meta-analysis of randomized controlled trials

Med Clin (Barc). 2015 Dec 21;145(12):511-9. doi: 10.1016/j.medcli.2015.03.014. Epub 2015 Jun 4.

Abstract

Background and objective: Romiplostim and eltrombopag are thrombopoietin receptor (TPOr) agonists that promote megakaryocyte differentiation, proliferation and platelet production. In 2012, a systematic review and meta-analysis reported a non-statistically significant increased risk of thromboembolic events for these drugs, but analyses were limited by lack of statistical power. Our objective was to update the 2012 meta-analysis examining whether TPOr agonists affect thromboembolism occurrence in adult thrombocytopenic patients.

Materials and methods: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). Updated searches were conduced on PubMed, Cochrane Central, and publicly available registries (up to December 2014). RCTs using romiplostim or eltrombopag in at least one group were included. Relative risks (RR), absolute risk ratios (ARR) and number needed to harm (NNH) were estimated. Heterogeneity was analyzed using Cochran's Q test and I(2) statistic.

Results: Fifteen studies with 3026 adult thrombocytopenic patients were included. Estimated frequency of thromboembolism was 3.69% (95% CI: 2.95-4.61%) for TPOr agonists and 1.46% (95% CI: 0.89-2.40%) for controls. TPOr agonists were associated with a RR of thromboembolism of 1.81 (95% CI: 1.04-3.14) and an ARR of 2.10% (95% CI: 0.03-3.90%) meaning a NNH of 48. Overall, we did not find evidence of statistical heterogeneity (p=0.43; I(2)=1.60%).

Conclusions: Our updated meta-analysis suggested that TPOr agonists are associated with a higher risk of thromboemboembolic events compared with controls, and supports the current recommendations included in the European product information on this respect.

Keywords: Eltrombopag; Ensayo clínico aleatorizado controlado; Meta-analysis; Randomized controlled trials; Romiplostim; Thrombocytopenia; Thromboembolism; Thrombosis; Trombocitopenia; Tromboembolismo; Trombopoyetina; Trombosis.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Adult
  • Benzoates / adverse effects*
  • Benzoates / therapeutic use
  • Hematologic Agents / adverse effects*
  • Hematologic Agents / therapeutic use
  • Humans
  • Hydrazines / adverse effects*
  • Hydrazines / therapeutic use
  • Models, Statistical
  • Pyrazoles / adverse effects*
  • Pyrazoles / therapeutic use
  • Randomized Controlled Trials as Topic
  • Receptors, Fc / therapeutic use
  • Receptors, Thrombopoietin / antagonists & inhibitors*
  • Recombinant Fusion Proteins / adverse effects*
  • Recombinant Fusion Proteins / therapeutic use
  • Thrombocytopenia / drug therapy*
  • Thromboembolism / chemically induced*
  • Thrombopoietin / adverse effects*
  • Thrombopoietin / therapeutic use

Substances

  • Benzoates
  • Hematologic Agents
  • Hydrazines
  • Pyrazoles
  • Receptors, Fc
  • Receptors, Thrombopoietin
  • Recombinant Fusion Proteins
  • Thrombopoietin
  • romiplostim
  • eltrombopag