ELBONIX (ELTROMBOPAG) 25MG TABLETS 28's

ELBONIX contains eltrombopag olamine, a small molecule thrombopoietin receptor agonist that binds to and activates the thrombopoietin receptor (c-Mpl) on megakaryocytes and their progenitors in the bone marrow.

This stimulates platelet production (thrombopoiesis), increasing circulating platelet counts without stimulating platelet activation or aggregation.

ELBONIX 25 mg is indicated for:

·       Chronic immune thrombocytopenia (ITP) in adults and children aged 1 year and above who are refractory to other treatments (e.g., corticosteroids, immunoglobulins);

·       Thrombocytopenia associated with hepatitis C virus (HCV) infection to enable initiation and maintenance of interferon-based therapy

·       Severe aplastic anaemia (SAA) in patients refractory to or relapsed after prior immunosuppressive therapy (IST).

Eltrombopag is an oral agent that provides a convenient alternative to parenteral treatments for raising platelet counts. It does not induce platelet activation, distinguishing it from standard procoagulants.

ELBONIX must be taken on an empty stomach (at least 30 minutes before or 2 hours after food, especially dairy products). Food — particularly calcium-containing foods — significantly reduces absorption.

Dosing for Chronic ITP (Adults and Adolescents 12 years and above)

•       Starting dose: 50 mg once daily (two 25 mg tablets).

•       Dose adjustment: based on platelet count response, adjust by 25 mg increments every 2 weeks.

•       Maximum dose: 75 mg once daily.

Dosing for East Asian Patients (ITP)

•       Starting dose: 25 mg once daily (one tablet) — East Asian patients (Chinese, Japanese, Korean) have higher eltrombopag exposure and should start at 25 mg.

Dose Reduction in Hepatic Impairment

•       Reduce dose in patients with moderate or severe hepatic impairment (Child-Pugh B or C): starting dose 25 mg once daily.

Target Platelet Count

•       The goal is to achieve and maintain a platelet count sufficient to reduce the risk of clinically important bleeding (generally greater than or equal to 50 x 10^9/L). Do not aim for a normal platelet count.

Common Side Effects

•       Nausea.

•       Headache.

•       Diarrhoea.

•       Upper respiratory tract infections.

•       Nasopharyngitis.

•       Elevated liver enzymes (ALT, AST) — liver function monitoring is required.

Serious Side Effects

•       Hepatotoxicity — jaundice, right upper quadrant pain, dark urine: stop immediately and seek assessment.

•       Thromboembolic events — including portal vein thrombosis, deep vein thrombosis, pulmonary embolism. Risk is higher with platelet counts above 200 x 10^9/L.

•       Bone marrow reticulin deposition — long-term use may cause bone marrow fibrosis; monitor with regular peripheral blood films.

•       Cataract formation — ocular monitoring is recommended during long-term therapy.

•       Rebound thrombocytopenia — platelet count may fall below baseline on discontinuation, increasing bleeding risk.

Hepatotoxicity Monitoring

Eltrombopag can cause hepatotoxicity. Liver function tests (ALT, AST, bilirubin) must be performed before starting treatment, every 2 weeks during dose adjustment, and monthly once stable. Discontinue if ALT rises to greater than 3 times the upper limit of normal in the presence of symptoms or bilirubin elevation.

Thromboembolism

Excessive platelet counts increase thrombotic risk. Never exceed a platelet count of 200 x 10^9/L — reduce dose or temporarily stop if this is exceeded. Patients with hepatitis C and cirrhosis are at particular risk of portal vein thrombosis.

Food and Chelation Interactions

Eltrombopag chelates polyvalent cations. Take on an empty stomach. Separate administration from dairy products, calcium supplements, antacids containing calcium/magnesium/aluminium/iron, and mineral supplements by at least 4 hours.

Aplastic Anaemia — Haematological Monitoring

In patients with severe aplastic anaemia, monitor peripheral blood film for dysplastic changes and cytogenetic analysis for clonal evolution (MDS/AML) at baseline and every 6 months during treatment.

Pregnancy

Based on its mechanism of action, eltrombopag may cause fetal harm. Women of childbearing potential must use effective contraception during and for 7 days after completing treatment. Inform prescriber immediately if pregnancy occurs.

•       Polyvalent cation supplements (calcium, magnesium, iron, aluminium, selenium, zinc) and antacids containing these — significantly reduce eltrombopag absorption; separate by at least 4 hours.

•       Rosuvastatin (and other OATP1B1/OATP1B3 substrate statins) — eltrombopag inhibits these transporters, increasing statin exposure and risk of myopathy; consider rosuvastatin dose reduction or switch to a different statin.

•       OAT1/OAT3 substrates (including methotrexate, penicillins) — eltrombopag may increase their plasma levels.

•       CYP1A2 and CYP2C8 substrates (repaglinide, paclitaxel) — eltrombopag inhibits these enzymes; monitor for increased substrate effects.

•       Store below 30 degrees Celsius.

•       Keep in original packaging.

•       Keep out of reach of children.

•       Do not use after the expiry date.

ELBONIX 25 mg is a prescription-only medicine (POM) in Kenya, regulated by the Pharmacy and Poisons Board (PPB). It must be initiated and supervised by a specialist haematologist.

Due to the complexity of dose titration, monitoring requirements, and serious adverse effect profile, ELBONIX is not appropriate for initiation in primary care settings.

Monitoring Schedule (ITP)

•       Platelet count: weekly until a stable dose is established for at least 4 weeks, then monthly.

•       LFTs (ALT, AST, bilirubin): before starting, every 2 weeks during dose adjustments, monthly once stable.

•       Peripheral blood film: every 6 months — assess for dysplastic features.

•       Ophthalmic review: annually — assess for cataracts in long-term users.

Dose Adjustment Algorithm

•       Platelet count below 50 x 10^9/L after 2 weeks: increase dose by 25 mg/day (up to 75 mg max).

•       Platelet count 50–150 x 10^9/L: maintain current dose.

•       Platelet count 150–250 x 10^9/L: reduce dose by 25 mg/day; wait 2 weeks before reassessing.

•       Platelet count above 250 x 10^9/L: stop temporarily; resume at lower dose when count falls below 100 x 10^9/L.

Rebound on Discontinuation

On stopping ELBONIX, platelet counts typically fall below pretreatment baseline within 2 weeks. Ensure close platelet monitoring for 4 weeks after discontinuation and manage thrombocytopenia with corticosteroids or IVIG if necessary.

Why must ELBONIX be taken on an empty stomach?

Food — particularly dairy products and foods containing calcium — significantly reduces the absorption of eltrombopag. Taking the tablet with food can reduce its effectiveness by up to 70%. Always take ELBONIX at least 30 minutes before eating or 2 hours after a meal.

How soon will my platelet count improve after starting ELBONIX?

Platelet counts typically begin to rise within 1–2 weeks of starting ELBONIX. Maximum response is usually seen within 4–8 weeks. Your blood count will be checked regularly so your doctor can adjust the dose to keep your platelet count in a safe range.

Can I stop ELBONIX when my platelet count is normal?

No — do not stop ELBONIX without discussing with your haematologist. When ELBONIX is stopped, platelet counts often fall below your pre-treatment baseline within 2 weeks, which can cause serious bleeding. Any dose reduction or stopping must be done gradually and under close medical supervision.