エポエチンアルファ
エポエチンアルファは組換えヒトエリスロポエチン（rHuEPO）であり、主に犬や猫の慢性腎不全に伴う非再生性貧血の治療に使用されます。獣医療では自己抗体が形成されるリスクが高く（20〜70％）、重篤な難治性貧血を引き起こす可能性があるため、通常は「最終手段」と見なされます。治療中は通常、鉄分の補給が必要です。
作用機序: Erythropoietin is an endogenous hormone primarily produced by the kidneys that regulates erythropoiesis. * **Receptor Binding:** Epoetin alfa binds to **erythropoietin receptors** on the surface of committed erythroid progenitor cells in the bone marrow. * **Proliferation & Differentiation:** This binding activates intracellular signaling pathways (such as JAK2/STAT5) → stimulates the survival, proliferation, and differentiation of red cell precursors. * **Reticulocyte Release:** It also accelerates the release of reticulocytes from the bone marrow into the systemic circulation, ultimately increasing the hematocrit and hemoglobin levels.
動物種別の用量
- Adjunctive therapy for anemia associated with endstage renal disease · Initially, 100 Units/kg SC 3 times weekly (or 48.4-145 Units/kg SC 3 times a week). · SC · 3 times weekly · Ongoing · Target hematocrit is 30-40%.
- Anemia associated with endstage renal disease (PCV <20%) · 75-100 Units/kg SC three times a week until PCV is in the low normal range (35%), then reduce dose and frequency to 50-75 Units/kg two times per week. · SC · 3 times a week initially · Ongoing · Administer iron at start of regime and until appetite is good.
- Problematic clinical signs and PCV <20% · Initially, 100 Units/kg SC 3 times per week. · SC · 3 times per week · Ongoing · Provide oral supplementation with ferrous sulfate (5-50 mg per cat per day). Reduce to twice per week when target PCV (30-40%) is reached.
- Anemia · 50-150 Units/kg IM 3 times weekly; may decrease to once weekly if RBC indices are significantly improved · IM · 3 times weekly · Ongoing
- Anemia (Rabbits) · 50-150 Units/kg SC every 2-3 days until PVC is normal; then once weekly (q7 days) for at least 4 weeks · SC · every 2-3 days initially · at least 4 weeks maintenance
- Adjunctive therapy for anemia associated with endstage renal disease · Initially, 100 Units/kg SC 3 times weekly, until the bottom of the target hematocrit range of 37-45% is attained. Once attained, change to twice weekly. As hematocrit approaches upper target, reduce to once weekly. Maintenance generally 75-100 Units/kg SC 1-2 times weekly. · SC · 3 times weekly initially · Ongoing · A lower initial dosage of 50-100 Units/kg 3 times weekly may be used. Iron supplementation required.
- Adjunctive therapy for anemia associated with endstage renal disease · Initially, 48.4-145 Units/kg SC three times a week. Most dogs should be started at 97 Units/kg SC 3 times a week. · SC · 3 times a week · Ongoing · Monitor hematocrit weekly until target 37-45% is reached, then decrease to two times weekly. Oral iron supplements recommended.
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
禁忌
- Uncontrolled hypertension
- Hypersensitivity to epoetin alfa
- Formation of significant autoantibodies with prior treatment
- Equines (not recommended for use)
有害事象
- Autoantibody formation (leading to refractory anemia)
- Systemic hypertension
- Vomiting
- Seizures
- Uveitis
- Iron depletion
- Local reactions at injection sites
- Fever
- Arthralgia
- Mucocutaneous ulcers
- Polycythemia (with chronic overdosage)
薬物相互作用
- Androgens · May increase the sensitivity of erythroid progenitors; safety of this combination is not fully determined.
- Desmopressin · Concurrent use with EPO can decrease bleeding times.
- Probenecid · Has been demonstrated to reduce the renal tubular excretion of EPO; clinical significance remains unclear.
- Iron supplements · Synergistic/Required; EPO increases demand for iron to synthesize hemoglobin for new RBCs · minor
モニタリング
- Hematocrit / PCV (weekly to every other week initially, then every 1-2 months)
- Blood Pressure (at least monthly initially)
- Renal Function Status
- Iron status (serum iron, TIBC)
- RBC indices
過量投与
Acute overdoses appear to be relatively free of adverse effects. Single doses of up to 1600 Units/kg in humans demonstrated no signs of toxicity. **Chronic overdoses** may lead to polycythemia or other adverse effects. Cautious phlebotomy may be employed should polycythemia occur.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。