ロムスチン
Lomustine
1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU)
別名: CeeNu · Belustine · Cecenu · CiNU · Citosta · Lomeblastin · Lucostine · Prava · CCNU · Gleostine · lomustinum · NSC-79037 · RB1509 · WR-139017
VetSheet 獣医チームが監修更新日 2026年4月5日エビデンスに基づく獣医学リファレンス
これは体表面積（mg/m²）に基づく用量です。投与前に体重を体表面積へ換算してください。
用量は獣医専門家向けの臨床参考資料です。必ず最新の医薬品情報および個別症例に基づいて確認してください。
動物種別用量
🌎 NA — North America🌍 EU — Europe
犬
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Antineoplastic (CNS neoplasms, lymphomas, mast cell tumors, histiocytic sarcomas) | 50-90 mg/m2 | PO | every 2-6 weeks | — | 🌎 NA |
| All uses (brain tumours, mast cell tumours, lymphoma, histiocytic sarcoma) | 60-80 mg/m2 | PO | q3-4wk | As directed by oncologist | 🌍 EU |
- Antineoplastic (CNS neoplasms, lymphomas, mast cell tumors, histiocytic sarcomas): Dosed in mg/m2, NOT mg/kg. Exact protocol depends on indication.
- All uses (brain tumours, mast cell tumours, lymphoma, histiocytic sarcoma): S-Adenosylmethionine and silybin may be used to prevent or treat hepatotoxicity.
猫
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Antineoplastic (CNS neoplasms, lymphomas, mast cell tumors) | 60 mg/m2 | PO | every 6 weeks | — | 🌎 NA |
| Antineoplastic (CNS neoplasms, lymphomas, mast cell tumors) | 10 mg | PO | every 3 weeks | — | 🌎 NA |
| All uses | 30-60 mg/m2 | PO | q4-6wk | As directed by oncologist | 🌍 EU |
- Antineoplastic (CNS neoplasms, lymphomas, mast cell tumors): Administered as a single 10 mg total dose.
- All uses: Dose is suggested but not well established. Specialist advice should be sought, as dosing intervals may need to be increased due to delayed myelosuppression.
用量は獣医専門家向けの臨床参考資料です。必ず最新の医薬品情報および個別症例に基づいて確認してください。
概要
ロムスチン（一般にCCNUとして知られる）は、高脂溶性のニトロソウレア系アルキル化抗悪性腫瘍薬です。脂溶性が高いため血液脳関門を容易に通過し、中枢神経系（CNS）の悪性腫瘍の治療において独自の価値を持っています。
主な獣医学的適応症：
- 肥満細胞腫（MCT）： 犬および猫の第一選択薬またはレスキュー療法として頻繁に使用されます。
- 組織球肉腫： 犬の局所性または播種性組織球肉腫の第一選択治療と見なされています。
- リンパ腫： 再発性多中心型リンパ腫のレスキュー薬として、または上皮向性（皮膚）リンパ腫の主要薬としてよく使用されます。
- CNS腫瘍： 原発性脳腫瘍（神経膠腫など）または転移性CNS病変に使用されます。
臨床のポイント： ロムスチンは、犬において遅発性、蓄積性、および不可逆的な可能性のある肝毒性を引き起こすことで知られています。多くの獣医腫瘍医は、肝保護剤（SAMeやシリマリンなど）の併用を強く推奨しています。
作用機序
Lomustine is a cell cycle-phase nonspecific antineoplastic drug, meaning it is toxic to cancer cells regardless of their current phase in the division cycle.
- Alkylating Activity: It undergoes spontaneous decomposition in vivo to form reactive intermediates. These intermediates transfer alkyl groups to DNA and RNA → causing cross-linking of DNA strands → preventing DNA replication and RNA transcription.
- Carbamoylation: The drug also causes carbamoylation of cellular proteins (specifically lysine residues) → inhibits DNA repair enzymes, preventing the cancer cell from fixing the alkylation damage, ultimately leading to apoptosis.
安全性・警告
禁忌
- Pre-existing severe bone marrow depression
- Active infections
- Pregnancy (Teratogenic - FDA Category D)
- Nursing/lactating animals
- Pre-existing bone marrow suppression
- Pre-existing liver disease
- Pregnancy and lactation
有害事象
- Bone marrow depression (anemia, thrombocytopenia, leukopenia) - nadirs typically at 1-6 weeks
- Hepatotoxicity (delayed, cumulative, chronic, and irreversible in dogs)
- Stomatitis
- Alopecia
- Corneal de-epithelization
- Renal toxicity (rare)
- Pulmonary infiltrates or fibrosis (rare)
- Myelosuppression (dose-limiting; severe neutropenia and thrombocytopenia)
- Hepatotoxicity (cumulative, dose-related, potentially irreversible in dogs)
- Gastrointestinal toxicity (vomiting, diarrhea, anorexia)
注意事項
Use only when potential benefits outweigh risks in patients with pre-existing anemia, bone marrow depression, pulmonary function impairment, current infection, impaired renal function, or sensitivity to lomustine. Extreme caution is required in patients who have received previous chemotherapy or radiotherapy due to compromised bone marrow reserves. Hepatotoxicity in dogs can be severe, delayed, and irreversible. Teratogenic in laboratory animals; suppresses gonadal function. Nursing puppies/kittens should receive milk replacer if the mother is treated.
医薬品相互作用
May increase the risk of severe infection due to additive immunosuppression.
Additive bone marrow depression; concurrent use should be avoided or strictly monitored.
Increased risk of vaccine-induced infection or decreased vaccine efficacy; use with extreme caution or avoid during therapy.
Increased risk of severe and potentially fatal bone marrow suppression.
Altered metabolism of lomustine, which requires hepatic microsomal enzyme hydroxylation. Use with caution.
Enhances the toxicity of lomustine (reported in humans).
監視
- CBC with platelets one week after dosing and prior to next dose (If platelets < 200,000/mcl, stop therapy until thrombocytopenia is resolved)
- Liver function tests (ALT, AST, ALP, Bilirubin) initially before starting treatment and then every 3-4 months
- Complete Blood Count (CBC) including platelets, particularly 7-14 days post-administration (and up to 6 weeks in cats)
- Liver function tests (ALT, AST, ALP, Bilirubin) prior to every dose
- Clinical signs of gastrointestinal toxicity
薬物動態
半減期
吸収
Absorbed rapidly and extensively from the GI tract. Some absorption occurs after topical administration.
分布
Lomustine and its active metabolites are widely distributed in the body. Highly lipophilic. While parent lomustine is not detected in the CSF, its active metabolites cross the blood-brain barrier and are detected in substantial concentrations.
代謝
Metabolized extensively in the liver to both active and inactive metabolites.
消失
Eliminated primarily in the urine.
過剰投与
Because of the severe potential toxicity of the drug (profound myelosuppression and hepatotoxicity), overdoses should be treated aggressively.
- Employ gut emptying protocols (emesis, activated charcoal) immediately if exposure was recent and the patient is asymptomatic.
- Provide aggressive supportive care and monitor CBC and liver enzymes closely.
- Consult an animal poison control center or a veterinary oncologist for specific guidance.
製品
製剤
- Capsules
- 40 mg oral capsule
ヒト用医薬品
- Lomustine Capsules: 10 mg, 40 mg & 100 mg with mannitol; CeeNu® (Bristol Labs Oncology); (Rx)
- 10 mg capsule
- 40 mg capsule
- 100 mg capsule
規制ステータス
POM (Prescription Only Medicine). Handled under cascade.
POM-V. Handled under the prescribing cascade.
規制データなし: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Store capsules in well-closed containers at room temperature. Expiration dates of two years are assigned after manufacture.
飼主向け情報
重要な安全性と取り扱いのガイドライン：
- 細胞毒性に対する予防措置： ロムスチンは抗がん剤です。カプセルを取り扱う際は使い捨て手袋を着用してください。カプセルを開けたり、砕いたり、分割したりしないでください。
- 廃棄物の管理： 投与後最大24時間（一部のプロトコルでは48〜72時間の予防措置を推奨）、ペットの尿や便から薬物およびその有毒な代謝物が検出される可能性があります。尿、便、嘔吐物を片付ける際は手袋を着用し、その後は手を十分に洗ってください。妊娠中の女性や免疫不全の人は、薬やペットの排泄物への接触を避けてください。
獣医師に連絡すべき場合：
- ロムスチンは重度の骨髄抑制および肝損傷を引き起こす可能性があります。
- ペットに感染の兆候、発熱、異常な内出血や出血、白目や歯茎の黄染（黄疸）、持続的な嘔吐、下痢が見られる場合、または単に無気力で具合が悪そうな場合は、直ちに獣医師に連絡してください。
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