マシチニブ
マシチニブは、主に犬の切除不能な肥満細胞腫（特に変異型c-KIT受容体が確認された症例）の治療に使用される**タンパク質チロシンキナーゼ阻害薬**です。アトピー性皮膚炎、炎症性腸疾患、骨肉瘤、血管肉腫などの他の炎症性および腫瘍性疾患への使用も研究されています。 > **臨床上の警告：** マシチニブは**細胞毒性薬（抗がん剤）**です。偶発的な曝露を防ぐため、獣医療スタッフおよび飼い主は厳格な安全・取り扱いプロトコルに従う必要があります。
作用機序: Masitinib acts as a **protein tyrosine kinase (TK) inhibitor**. It selectively and effectively binds with high affinity to mutated forms of the **c-KIT tyrosine kinase receptor**. **c-KIT receptor** → Inhibition blocks the TK receptor pathways that are essential for cell replication, survival, and differentiation, thereby halting tumor growth and progression.
動物種別の用量
- Non-resectable mast cell tumours (Patnaik grade 2 or 3) · See Appendix for chemotherapy protocols · PO · unknown · unknown · Preferably with a confirmed mutated c-KIT tyrosine kinase receptor.
- Injection site sarcoma, asthma (investigational) · Limited evidence: administered to healthy cats · PO · unknown · unknown · Not licensed in cats. Further clinical trials required. Monitor closely.
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
- Pregnant or lactating bitches
- Dogs < 24 months old
- Dogs < 7 kg body weight
- Pre-existing signs of myelosuppression
- Previous hypersensitivity to masitinib
有害事象
- Diarrhoea (mild to moderate)
- Vomiting (mild to moderate)
- Hair coat changes or alopecia
- Renal toxicity
- Anaemia
- Protein loss (protein-losing nephropathy/enteropathy)
- Myelosuppression
- Increased liver enzyme activity
- Lethargy
- Cough
- Lymphadenomegaly
薬物相互作用
- Highly protein-bound drugs · May displace masitinib or be displaced, increasing the risk of adverse side effects · moderate
- Cytochrome P450 inhibitors or inducers · May alter the metabolism of masitinib, increasing the risk of toxicity or reducing efficacy · moderate
モニタリング
- Blood pressure (baseline and monthly)
- Urinalysis (baseline and monthly)
- Haematology (baseline and monthly)
- Biochemistry (baseline and monthly)
- Coagulation profiles (if adverse signs witnessed)
- Faecal occult blood tests (if adverse signs witnessed)
- Weekly owner check-ins for the first 6 weeks to monitor for side effects
過量投与
No specific overdose information is provided in the monograph. > **Clinical Pearl:** Overdose of tyrosine kinase inhibitors typically exacerbates gastrointestinal toxicity (severe vomiting, diarrhea) and myelosuppression. Treatment is symptomatic and supportive. Monitor renal and hepatic parameters closely.
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。