In this article, we will discuss about Leflunomide (Dosage). So, let’s get started.
Leflunomide (ARAVA®) is a pyrimidine synthesis inhibitor. The chemical name for leflunomide is N-(4-trifluoromethylphenyl)-5-methylisoxazole-4-carboxamide. It has an empirical formula C12H9F3N2O2, a molecular weight of 270.2.
Leflunomide (ARAVA®) is available for oral administration as tablets containing 10, 20, or 100 mg of active drug. Combined with leflunomide are the following inactive ingredients: colloidal silicon dioxide, crospovidone, hypromellose, lactose monohydrate, magnesium stearate, polyethylene glycol, povidone, starch, talc, titanium dioxide, and yellow ferric oxide (20 mg tablet only).
Mechanism of Action
Leflunomide is an isoxazole immunomodulatory agent which inhibits dihydrocrotate dehydrogenase (an enzyme involved in de novo pyrimidine synthesis) and has antiproliferative activity. Several in vivo and in vitro experimental models have demonstrated an anti-inflammatory effect.
The recommended dosage of Leflunomide (ARAVA®) is 20 mg once daily. Treatment may be initiated with or without a loading dose, depending upon the patient’s risk of ARAVA-associated hepatotoxicity
and ARAVA-associated myelosuppression. The loading dosage provides steady-state
concentrations more rapidly.
• For patients who are at low risk for Leflunomide (ARAVA®)-associated hepatotoxicity and Leflunomide (ARAVA)-associated myelosuppression the recommended Leflunomide (ARAVA) loading dosage is 100 mg once daily for 3 days. Subsequently administer 20 mg once daily.
• For patients at high risk for Leflunomide (ARAVA®)-associated hepatotoxicity (e.g., those taking concomitant methotrexate) or Leflunomide (ARAVA®)-associated myelosuppression (e.g., patients taking concomitant immunosuppressants), the recommended Leflunomide (ARAVA®) dosage is 20 mg once daily without a loading dose.
The maximum recommended daily dosage is 20 mg once per day. Consider dosage reduction to 10 mg once daily for patients who are not able to tolerate 20 mg daily (i.e., for patients who experience any adverse effects).
Monitor patients carefully after dosage reduction and after stopping therapy with Leflunomide (ARAVA®), since the active metabolite of leflunomide, teriflunomide, is slowly eliminated from the plasma. After stopping Leflunomide (ARAVA®) treatment, an accelerated drug elimination procedure is recommended to reduce the plasma concentrations of the active WS metabolite, teriflunomide. Without use of an accelerated drug elimination procedure, it may take up to 2 years to reach undetectable plasma teriflunomide concentrations after stopping Leflunomide (ARAVA®).