Central European Expert Consensus on the Treatment of ITP in Adult Patients

Current Treatment Options for ITP

Immune thrombocytopenia is a rare autoimmune disorder characterized by the destruction of platelets caused by the presence of antibodies against them and other immunopathological processes. It is typically marked by an isolated drop in platelet count below 100 × 10⁹/l, leading to an increased risk of bleeding.

The goal of ITP treatment is to increase and maintain platelet counts above 30–50 × 10⁹/l, typically initiating treatment when platelet counts drop below 30 × 10⁹/l and hemorrhagic diathesis occurs. Based on disease progression, ITP is categorized as newly diagnosed (up to 3 months from the first symptoms), persistent (3−12 months), and chronic (lasting over a year).

Treatment is determined by the duration of symptoms, with the standard 1st line treatment being corticosteroids (up to 6 weeks), possibly followed by intravenous immunoglobulins (IVIG). In cases of inadequate response or relapse, 2nd line treatments include thrombopoietin receptor agonists (TPO-RA), rituximab, other immunomodulatory drugs (e.g., fostamatinib), and splenectomy.

Currently, in the EU, the TPO-RA approved for 2nd line treatment of adult patients with primary ITP include romiplostim (s.c. administration once a week), eltrombopag, and avatrombopag (both administered orally once daily). These drugs have a similar mechanism of action; however, their binding sites to TPO receptors may differ. Direct comparisons of individual TPO-RAs in clinical settings have not yet been conducted. 

Main Points of the Consensus

A panel of experts from 8 Central European countries conducted a systematic literature review of the last 10 years (up to June 2022). Using the Delphi method, teleconferences, and email correspondence, they reached a consensus on the use of TPO-RAs in the 2nd line treatment of ITP. Consensus on the use of TPO-RAs in the 1st line treatment of ITP and in patients with chronic ITP and COVID-19 was not reached.

The panel issued the following recommendations:

• TPO-RAs are the preferred 2nd line treatment for adult patients with chronic ITP who are refractory to corticosteroids or IVIG.
• In patients with newly diagnosed or persistent ITP, the same efficacy and safety of TPO-RAs can be expected as in patients with chronic ITP.
• In patients with chronic ITP who do not respond, lose response, have fluctuating platelet counts, or experience side effects with one or two TPO-RAs, switching to another TPO-RA is recommended.
• In individuals who have achieved stable platelet counts above 100 × 10⁹/l and have no bleeding symptoms for at least 12 months with TPO-RA treatment without other medications, a dose reduction or gradual discontinuation of TPO-RAs should be considered.
• Experts recommend romiplostim or avatrombopag for patients with specific dietary restrictions, as unlike eltrombopag, they have no dietary restrictions. Romiplostim is also the only parenteral TPO-RA and may be suitable for patients with gastrointestinal issues (diarrhea, vomiting, gastrointestinal surgery). 
• In patients with chronic ITP and concurrent liver dysfunction, a TPO-RA with a very low risk of liver side effects (e.g., avatrombopag) may be preferred.
• Temporary off-label use of TPO-RAs may be exceptionally considered in late pregnancy (for instance, in women with severe refractory ITP or when corticosteroids or IVIG are contraindicated).

Conclusion

These recommendations can assist physicians in clinical practice in making informed decisions about the treatment of adult ITP patients.

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Source: Pulanić D. et al. Use of thrombopoietin receptor agonists in adults with immune thrombocytopenia: a systematic review and Central European expert consensus. Ann Hematol 2023 Apr; 102 (4): 715–727, doi: 10.1007/s00277-023-05114-8.