Generic Name and Formulations:
Lubiprostone 8mcg, 24mcg; caps.
Company:
Sucampo and Takeda
Indications for AMITIZA:
Irritable bowel syndrome with constipation (IBS–C) in women.
Adult Dose for AMITIZA:
Swallow whole. Take with food and water. ≥18yrs: 8mcg twice daily. Severe hepatic impairment (Child-Pugh Class C): 8mcg once daily.
Children's Dose for AMITIZA:
<18yrs: not recommended.
Pharmacological Class:
GI motility enhancer (chloride channel activator).
Contraindications:
Known or suspected mechanical GI obstruction.
Warnings/Precautions:
Confirm absence of GI obstruction before starting therapy. Severe diarrhea: not recommended. Renal or hepatic impairment. Reevaluate periodically. Pregnancy (Cat.C). Nursing mothers; monitor infants for diarrhea.
Interactions:
Possibly antagonized by diphenylheptane opioids (eg, methadone).
Adverse Reactions:
Nausea, headache, diarrhea (suspend therapy if occurs), abdominal pain, abdominal distension, flatulence, dyspnea, vomiting, syncope, asthenia, others.
Elimination:
Renal (primary), fecal.
How Supplied:
8mcg—60; 24mcg—60, 100
2013年10月25日，Sucampo制药和合作伙伴武田（Takeda）宣布，启动一项关键性试验，在慢性特发性便秘（CIC）成人患者中调查液体剂型鲁比前列酮（lubiprostone，24mcg BID）的药效学、药代动力学、耐受性。
鲁比前列酮（lubiprostone）是全球首个氯离子通道激活剂，能够增加肠液的分泌，软化粪便并增加肠道的蠕动，从而利于大便的推移，并缓解CIC相关症状。
该关键性试验是一项随机、安慰剂对照、双盲、多中心研究，将在确诊为慢性便秘且年龄在18岁及以上的成人患者中开展，将调查液体剂型lubiprostone的药效学、药代动力学、耐受性。该项研究预计将在美国11个位点招收152名患者。
该项研究的数据，预计将于2014年底获得，之后Sucampo计划提交液体剂型lubiprostone的新药申请（NDA）。作为其全球性、多中心III期项目的一部分，Sucampo还计划在儿童患者中调查液体配方lubiprostone。
关于鲁比前列酮（lubiprostone）：
lubiprostone目前已以商品名AMITIZA在美国上市。AMITIZA胶囊适用于成人慢性特发性便秘（CIC）、成人慢性非癌痛阿片诱导性便秘（OIC）的治疗。此外，AMITIZA还适用于18岁以上女性便秘型肠易激综合征（IBS-C）的治疗。
Amitiza: new treatment option for chronic idiopathic constipation
Amitiza (lubiprostone) is a first-in-class treatment for chronic idiopathic constipation when diet and other non-pharmacological measures are inappropriate or inadequate.
PHARMACOLOGY
Lubiprostone is a prostone that selectively activates chloride channels to increase intestinal fluid secretion without altering serum electrolyte concentrations. This increases intestinal motility and the passage of stool whilst alleviating symptoms associated with chronic idiopathic constipation.1
CLINICAL STUDIES
Three double-blind, placebo-controlled studies evaluated the safety and efficacy of lubiprostone 24 microgram twice daily in patients with chronic idiopathic constipation, defined as less than three spontaneous bowel movements (SBMs) per week in the absence of enema or suppository use.1–3
The primary outcome measure was the mean number of SBMs at the end of week 1 for the first and second studies and the change from baseline in SBM frequency at week 1 for the third study.1–3
Bowel movements increased
In the first study (n=242), the mean number of SBMs at the end of week 1 was significantly greater in the lubiprostone-treated group than in the placebo group (5.69 vs 3.46, p=0.0001). Of the 120 patients given lubiprostone, 56.7% reported an SBM within 24 hours of the first dose compared with 36.9% of the 122 who received placebo (p=0.0024).2
Similar results were seen in the second study involving 237 patients (mean number of SBMs 5.89 with lubiprostone vs 3.99 with placebo, p=0.0001), with a greater percentage of patients treated with lubiprostone having an SBM within the first 24 hours (61.3% vs 31.4%, p<0.0001).3
In the third study (n=124), the change from baseline in SBM frequency at week 1 was significantly greater for lubiprostone than placebo: 3.66 versus 1.26 (p<0.001).1
Lubiprostone maintained this superiority to placebo through weeks 2–4 of therapy in all studies. Patients who were given lubiprostone reported significant improvements in stool consistency, straining and severity of constipation at all timepoints.2,3
Well tolerated
Lubiprostone was generally well tolerated in all three studies, with nausea, diarrhoea and headache the most commonly observed adverse effects.1
To reduce the risk of nausea, patients should be advised to take lubiprostone with food. In addition, patients should be advised to inform the prescriber if severe diarrhoea, dyspnoea or chest discomfort occurs.1–3
Long-term safety
The long-term safety and tolerability of lubiprostone were assessed in three open-label studies involving 784 patients with chronic idiopathic constipation receiving 24 microgram twice daily for 12 months. Results from these studies showed a decrease in constipation severity, abdominal bloating and discomfort over the treatment period. Lubiprostone remained well tolerated.1
Dose changes
Lubiprostone requires no change in dosage for the elderly or patients with renal impairment; however, patients with moderate to severe hepatic impairment should take a reduced dose of one capsule once daily.1