Lysteda（氨甲环酸片）作为首个非激素类药物美国食品药品管理局（FDA）于2009年11月13日批准上市用于治疗月经期出血量过多。
FDA通报：美国每年有大约300,0000名育龄妇女出现月经期出血量过多现象。患有子宫平滑肌瘤的妇女可能还会出现月经期过长症状，但大多数情况下，经血过多与子宫平滑肌瘤并没有潜在的联系。
氨甲环酸（Tranexamic acid）于1986年首次在美国以注射剂形式获批，商品名为Cyklokapron，主要用于血友病（一种由于缺少凝血因子而导致凝血障碍的遗传性疾病）患者拔牙过程中及拔牙后的止血和预防出血。
Lysteda的临床试验显示，Lysteda最常见的不良反应主要包括头痛、鼻窦症状、背痛、腹痛、肌肉和关节疼痛、肌肉痛性痉挛、贫血和疲劳等症状。接受安慰剂组妇女与接受ysteda治疗的妇女在经期出血量方面的差异具有统计学意义。
FDA药品审评与研究中心生殖与泌尿外科部主任、医学博士Scott Monroe认为，Lysteda与激素类避孕药同时使用可能会使出现血栓、中风、心脏病发作的风险增大。使用激素类避孕药的女性只有在具有强烈的用药需求或使用后的收益大于潜在风险时才能够同时服用Lysteda。
Manufacturer:
Ferring Pharmaceuticals, Inc.
Pharmacological Class:
Antifibrinolytic
Active Ingredient(s):
Tranexamic acid 650mg; tabs.
Indication(s):
Cyclic heavy menstrual bleeding.
Pharmacology:
Compared to women with normal menstrual bleeding, women with heavy menstrual bleeding have elevated concentrations of endometrial, uterine, and menstrual blood tissue plasminogen activator (tPA).
Tranexamic acid is a derivative of the amino acid lysine that diminishes the dissolution of hemostatic fibrin by plasmin. Tranexamic acid occupies the binding sites for lysine on plasmin, preventing binding to fibrin monomers, thus preserving and stabilizing fibrin’s matrix structure. Saturation of the high affinity lysine binding site on plasminogen displaces plasminogen from the surface of fibrin.
This drug is eliminated primarily by glomerular filtration, with more than 95% eliminated unchanged. Patients with renal dysfunction therefore require a reduction in dose.
Clinical Trials:
A 3-cycle treatment study and a 6-cycle treatment study were conducted to establish the safety and efficacy of tranexamic acid in the treatment of heavy menstrual bleeding. In these randomized, double-blind, placebo-controlled studies, the primary outcome measure was menstrual blood loss (MBL), and the endpoint was the change from baseline in MBL.
In the 3-cycle study, two different doses of tranexamic acid (1950mg/day or 3900mg/day for up to 5 days per cycle) were compared to placebo. Of 294 evaluable patients, 115 were randomized to the 3900mg/day dose; these patients had significantly reduced MBL, compared to those given placebo.
In the 6-cycle study, tranexamic acid 3900mg/day given for up to 5 days/cycle was compared to placebo. This study had 187 evaluable patients, 115 of whom were randomized to receive the study drug. A significant reduction in MBL resulted from treatment with the study drug, compared to placebo. Study success also required achieving a reduction in MBL that was clinically meaningful for the subjects.
In both studies, treatment with tranexamic acid 3900mg/day was associated with a reduction in limitations on social, leisure, and physical activities.
Legal Classification:
Rx
Adults:
Treat for up to 5 days during menses. Swallow whole. ≥18yrs: Normal renal function (serum creatinine ≤1.4mg/dL): 1300mg three times daily; Cr >1.4–2.8mg/dL: 1300mg twice daily; Cr >2.8–5.7mg/dL: 1300mg once daily; Cr >5.7mg/dL: 650mg once daily.
Children:
<18yrs: not studied.
Contraindication(s):
Active thromboembolic disease (eg, DVT, pulmonary embolism, cerebral thrombosis). History or risk of thrombosis or thromboembolism (eg, retinal vein or artery occlusion; thrombogenic valvular disease, thrombogenic cardiac rhythm disease, hypercoagulopathy).
Warnings/Precautions:
Exclude endometrial pathology first. Renal impairment. Subarachnoid hemorrhage (cerebral edema/infarction may occur). Acute promyelocytic leukemia treated with oral tretinoin (increased procoagulant effect). Pregnancy (Cat.B). Nursing mothers.
Interaction(s):
Increased risk of thrombotic events (eg, stroke, MI) with hormonal contraceptives, Factor IX products, anti-inhibitor coagulant concentrates, oral tretinoin. Tissue plasminogen activators may decrease efficacy of both tranexamic acid and tPAs.
Adverse Reaction(s):
Headache, sinus/nasal symptoms, pain (back, abdomen, musculoskeletal, joint), muscle cramps, migraine, anemia, fatigue; visual/ocular events (retinal occlusion; discontinue if occurs), severe allergic reaction.
How Supplied:
Tabs—30, 100, 500
