2011年4月29日，Spectrum Pharmaceuticals公司宣布，美国食品药品管理局(FDA)已批准了Fusilev(左旋亚叶酸)的一项新适应证。该药现已获准与5-氟尿嘧啶联用，作为晚期转移性结直肠癌患者的姑息治疗。Fusilev是一种叶酸类似物，已获准的剂型包括即用的175 mg和250 mg两种瓶装注射液以及一种50 mg瓶装冻干粉剂。
除了结直肠癌外，Fusilev还可用作骨肉瘤患者行高剂量甲氨蝶呤治疗后的补救治疗药。此外，Fusilev的适应证还包括减轻化疗药物的毒性，对抗甲氨蝶呤消除受损和叶酸拮抗剂意外过量所产生的不良影响。
据Spectrum Pharmaceuticals公司的发言人称，美国国家综合癌症网(NCCN)结直肠癌治疗指南已经推荐将左旋亚叶酸用于治疗结直肠癌。
晚期结直肠癌患者在采用Fusilev联合5-氟尿嘧啶治疗方案后最常发生的不良反应为腹泻、恶心和胃炎。Fusilev可以与抗癫痫药发生相互作用，其中包括苯巴比妥、苯妥英以及普里米酮，并可增加疑似患者的癫痫发作频率。
Fusilev禁用于既往曾发生叶酸或亚叶酸过敏反应的患者。由于其含有钙，故每分钟静脉输注的左旋亚叶酸注射液量不得超过16 ml(160 mg)。
Generic Name and Formulations:
Levoleucovorin (as calcium pentahydrate) 50mg/vial; pwd for IV inj after reconstitution; contains mannitol 50mg/vial; 175mg/17.5mL; soln for IV inj; preservative-free.
Company:
Spectrum Pharmaceuticals, Inc.
Indications for FUSILEV:
Palliative treatment of advanced metastatic colorectal cancer in combination with 5-fluorouracil (5-FU).
Adult Dose for FUSILEV:
Administer levoleucovorin and 5-FU separately to avoid precipitate formation. Regimen 1: give levoleucovorin at 100mg/m2 by slow IV inj over a minimum of 3 minutes, followed by 5-FU at 370mg/m2 by IV inj. Regimen 2: give levoleucovorin at 10mg/m2 by IV inj, followed by 5-FU at 425mg/m2 by IV inj. Both: Treat daily for 5 days. Five-day treatment course may be repeated at 4 week (28 days) intervals for 2 courses, and then repeated at 4–5 week (28–35 days) intervals provided that patient recovered completely from toxic effects from prior treatment course. Dose adjustments for subsequent treatment course: see literature.
Children's Dose for FUSILEV:
Not recommended.
Pharmacological Class:
Folate analogue.
Warnings/Precautions:
Not for treating pernicious anemia and megaloblastic anemia. Elderly. Debilitated. Pregnancy (Cat.C). Nursing mothers.
Interactions:
Potentiates 5-fluorouracil toxicity. Antagonizes TMP/SMZ. Antagonizes anticonvulsants (eg, phenobarbital, primidone, phenytoin). May be affected by drugs that affect MTX elimination.
Adverse Reactions:
Stomatitis, nausea, diarrhea.
Generic Availability:
NO
How Supplied:
Single-use vial (pwd, soln)—1
