Eltrombopag

PRESCRIBING CONTEXT: treatment should be initiated by and remain under the supervision of a physician experienced in haematological disease or in the management of chronic hepatitis C and its complications. Dosing must be individualised on platelet count; use the lowest dose that achieves and maintains a platelet count of at least 50,000/microlitre. Platelet counts generally rise within 1-2 weeks of starting and fall within 1-2 weeks of stopping. ITP DOSE ADJUSTMENT (wait at least 2 weeks between adjustments; the standard adjustment step is 25 mg once daily): platelet count under 50,000/microlitre after at least 2 weeks of therapy — increase the daily dose by 25 mg to a maximum of 75 mg/day (for patients taking 25 mg every other day, increase to 25 mg once daily); 50,000 to 150,000/microlitre — use the lowest dose of eltrombopag and/or concomitant ITP treatment that avoids or reduces bleeding; over 150,000 up to 250,000/microlitre — decrease the daily dose by 25 mg and wait 2 weeks to assess (for patients on 25 mg once daily, consider 12.5 mg once daily or 25 mg every other day); over 250,000/microlitre — stop eltrombopag, increase platelet monitoring to twice weekly and, once the count is 100,000/microlitre or less, restart at a daily dose reduced by 25 mg. MONITORING: full blood counts including platelet count and peripheral blood smears weekly until a stable platelet count (at least 50,000/microlitre for at least 4 weeks) is achieved, then monthly; monitor clinical haematology and liver tests regularly (ALT, AST and bilirubin before starting, every 2 weeks during dose adjustment and monthly once stable). DISCONTINUATION: stop if the platelet count does not rise enough to avoid clinically important bleeding after 4 weeks at 75 mg once daily; thrombocytopenia may recur on stopping; in non-splenectomised patients, periodic evaluation should include consideration of splenectomy. CHRONIC HEPATITIS C-ASSOCIATED THROMBOCYTOPENIA: start at 25 mg once daily (no adjustment needed for East-/Southeast-Asian ancestry or mild hepatic impairment); adjust in 25 mg increments every 2 weeks to reach the platelet count required to start antiviral therapy; target platelets normally around 50,000-75,000/microlitre and avoid counts above 75,000/microlitre; monitor platelets weekly before antiviral therapy and weekly during it until stable, then monthly. PAEDIATRIC (ITP, flat doses — not per kg): 6 to 17 years, 50 mg once daily (25 mg once daily for East-/Southeast-Asian ancestry); 1 to 5 years, 25 mg once daily. FORMULATION SWITCH: the powder for oral suspension may give higher exposure than tablets — monitor platelet counts weekly for 2 weeks when switching. HEPATIC IMPAIRMENT: use caution; a lower starting dose is used in ITP and severe aplastic anaemia patients, with close monitoring. NOT CAPTURED IN THIS EXTRACT: the severe aplastic anaemia posology and the hepatic-impairment starting dose were truncated out of the fetched §4.2 — verify against the full SPC. For reference only, the US label states a maximum of 100 mg/day for chronic hepatitis C-associated thrombocytopenia and a 150 mg once-daily start for first-line severe aplastic anaemia in patients 12 years and over — US figures, not confirmed by the UK SPC extract.