英文药名：Sivextro（Tedizolid phosphate injection） 中文药名：磷酸酯静脉注射剂 生产厂家：Cubist Pharmaceuticals，Inc. 药品介绍 SIVEXTRO (Tedizolid磷酸酯)为注射静脉使用 美国批准上市日期：2014年6月20日 适应证和用途 SIVEXTRO是一种恶唑烷酮类抗细菌药适用在成年为治疗由指定易感细菌所致急性细菌性皮肤和皮肤结构感染(ABSSSI)。 为减低耐药细菌的发生和维持SIVEXTRO和其他抗细菌药的有效性，SIVEXTRO只应用于治疗或预防被证明或强烈怀疑是被细菌所致感染。 剂量和给药方法 200 mg每天1次口服或作为静脉(IV)历时1小时输注给予共6天。 剂型和规格 ⑴为注射：200mg，无菌，冻干粉在为静脉输注重建单次使用小瓶； ⑵片：200mg 禁忌证 无。 警告和注意事项 ⑴患者有粒细胞减少：尚未曾适当地在有粒细胞减少(中性粒细胞计数<1000细胞/mm3)患者中评价SIVEXTRO的安全性和疗效。在一个感染的动物模型，SIVEXTRO的抗细菌活性在缺乏粒细胞时减低。中性粒细胞减少患者考虑替代疗法。 ⑵难辨梭状芽孢杆菌[Clostridium difficile]-伴随腹泻：如发生腹泻评价。 不良反应 最常见不良反应(>2%)是恶心，头痛，腹泻，呕吐，和眩晕。 包装规格： 200mg/支*10支/ 盒 SIVEXTRO（磷酸特地唑胺 tedizolid phosphate）是由CUBIST PHARMS公司研发的新型抗细菌感染用药。于2014年6月20日获批准磷酸特地唑胺（商品名为SIVEXTRO）上市，用于特定的敏感细菌引起的成人急性细菌性皮肤和皮肤结构感染（ABSSSI）。 Sivextro 200 mg powder for concentrate for solution for infusion 1. Name of the medicinal product Sivextro 200 mg powder for concentrate for solution for infusion 2. Qualitative and quantitative composition Each vial contains disodium tedizolid phosphate corresponding to 200 mg tedizolid phosphate. After reconstitution each mL contains 50 mg tedizolid phosphate. For the full list of excipients, see section 6.1. 3. Pharmaceutical form Powder for concentrate for solution for infusion (powder for concentrate). White to off-white powder. 4. Clinical particulars 4.1 Therapeutic indications Sivextro is indicated for the treatment of acute bacterial skin and skin structure infections (ABSSSI) in adults (see sections 4.4 and 5.1). Consideration should be given to official guidance on the appropriate use of antibacterial agents. 4.2 Posology and method of administration Posology Tedizolid phosphate film-coated tablets or powder for concentrate for solution for infusion may be used as initial therapy. Patients who commence treatment on the parenteral formulation may be switched to the oral one when clinically indicated. Recommended dose and duration The recommended dosage is 200 mg once daily for 6 days. The safety and efficacy of tedizolid phosphate when administered for periods longer than 6 days have not been established in patients (see section 4.4). Missed dose If a dose is missed it should be given to the patient as soon as possible anytime up to 8 hours prior to the next scheduled dose. If less than 8 hours remains before the next dose, then the physician should wait until the next scheduled dose. A double dose should not be given to compensate for a missed dose. Elderly (≥65 years) No dosage adjustment is required (see section 5.2). The clinical experience in patients ≥75 years is limited. Hepatic impairment No dosage adjustment is required (see section 5.2). Renal impairment No dosage adjustment is required (see section 5.2). Paediatric population The safety and efficacy of tedizolid phosphate in children and adolescents below 18 years of age have not yet been established. Currently available data are described in section 5.2, but no recommendation on a posology can be made. Method of administration Sivextro must be administered by intravenous infusion over a 60-minute period. For instructions on reconstitution and dilution of the medicinal product before administration, see section 6.6 4.3 Contraindications Hypersensitivity to the active substance or to any of the excipients listed in section 6.1. 4.4 Special warnings and precautions for use Patients with neutropenia The safety and efficacy of tedizolid phosphate in patients with neutropenia (neutrophil counts <1000 cells/mm3) have not been investigated. In an animal model of infection, the antibacterial activity of tedizolid phosphate was reduced in the absence of granulocytes. The clinical relevance of this finding is unknown. Alternative therapies should be considered when treating patients with neutropenia and ABSSSI (see section 5.1). Mitochondrial dysfunction Tedizolid inhibits mitochondrial protein synthesis. Adverse reactions such as lactic acidosis, anaemia and neuropathy (optic and peripheral) may occur as a result of this inhibition. These events have been observed with another member of the oxazolidinone class when administered over a duration exceeding that recommended for Sivextro Myelosuppression Decreased platelets, decreased haemoglobin and decreased neutrophils have been observed in a few subjects during treatment with tedizolid phosphate. In cases where tedizolid was discontinued, the affected haematological parameters have returned back to pre-treatment levels. Myelosuppression (including anaemia, leucopenia, pancytopenia and thrombocytopenia) has been reported in patients treated with another member of the oxazolidinone class and the risk of these effects appeared to be related to the duration of treatment. Peripheral neuropathy and optic nerve disorders Peripheral neuropathy, as well as optic neuropathy sometimes progressing to loss of vision, have been reported in patients treated with another member of the oxazolidinone class with treatment durations exceeding that recommended for Sivextro. Neuropathy (optic and peripheral) has not been been reported in patients treated with tedizolid phosphate at the recommended treatment duration of 6 days. All patients should be advised to report symptoms of visual impairment, such as changes in visual acuity, changes in colour vision, blurred vision, or visual field defect. In such cases, prompt evaluation is recommended with referral to an ophthalmologist as necessary. Lactic acidosis Lactic acidosis has been reported with the use of another member of the oxazolidinone class. Lactic acidosis has not been been reported in patients treated with tedizolid phosphate at the recommended treatment duration of 6 days. Hypersensitivity reactions Tedizolid phosphate should be administered with caution in patients known to be hypersensitive to other oxazolidinones since cross-hypersensitivity may occur. Clostridium difficile associated diarrhoea Clostridium difficile associated diarrhoea (CDAD) has been reported for tedizolid phosphate (see section 4.8). CDAD may range in severity from mild diarrhoea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon and may permit overgrowth of C. difficile. CDAD must be considered in all patients who present with severe diarrhoea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, tedizolid phosphate and, if possible, other antibacterial agents not directed against C. difficile should be discontinued and adequate therapeutic measures should be initiated immediately. Appropriate supportive measures, antibiotic treatment of C. difficile, and surgical evaluation should be considered. Medinical products inhibiting peristalsis are contraindicated in this situation. Monoamine oxidase inhibition Tedizolid is a reversible, non-selective inhibitor of monoamine oxidase (MAO) in vitro (see section 4.5). Serotonin syndrome Spontaneous reports of serotonin syndrome associated with the co-administration of another member of the oxazolidinone class together with serotonergic agents have been reported (see section 4.5). There is no Phase 3 clinical experience in patients with co-administration of Sivextro with serotonergic agents such as selective serotonin re-uptake inhibitors [SSRI], serotonin norepinephrine reuptake inhibitors (SNRI), tricyclic antidepressants, MAO inhibitors, triptans, and other medications with potential adrenergic or serotonergic activity. Non-susceptible microorganisms Prescribing tedizolid phosphate in the absence of a proven or strongly suspected bacterial infection increases the risk of the development of drug-resistant bacteria. Tedizolid phosphate is generally not active against Gram-negative bacteria. Women of childbearing potential Women of childbearing potential must use reliable contraception while taking tedizolid phosphate. It is currently unknown whether tedizolid phosphate may reduce the effectiveness of hormonal contraceptives, and therefore women using hormonal contraceptives must use an additional method of contraception (see section 4.5). Limitations of the clinical data The safety and efficacy of tedizolid phosphate when administered for periods longer than 6 days have not been established. In ABSSSI, the types of infections treated were confined to cellulitis/erysipelas or major cutaneous abscesses, and wound infections only. Other types of skin infections have not been studied. There is limited experience with tedizolid phosphate in the treatment of patients with concomitant acute bacterial skin and skin structure infections and secondary bacteremia and no experience in the treatment of ABSSSI with and severe sepsis or septic shock. Controlled clinical studies did not include patients with neutropenia (neutrophil counts <1000 cells/mm3) or severely immunocompromised patients. 4.5 Interaction with other medicinal products and other forms of interaction Pharmacokinetic interactions Based on in vitro results, there is a risk for enzyme induction by tedizolid phosphate. This may result in reduced efficacy of co-administered medicinal products that are narrow substrates of CYP3A4 (such as oral midazolam, triazolam, alfentanil, cyclosporine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus), CYP2B6 (efavirenz), CYP2C9 (warfarin), and P-gp (digoxin). The enzyme induction by tedizolid phosphate may also reduce the efficacy of oral hormonal contraceptives (see section 4.4). This is not a complete list; please consult the SmPC of the co-administered medicinal product. There is a potential for tedizolid phosphate to inhibit organic anion transporter (OATP1B1) based on in vitro data. The in vivo relevansce is unknown. The OATP1B1 inhibition could result in increased exposure of medicinal products such as statins (atorvastatin, fluvastatin, pitavastatin, and lovastatin), repaglinide, bosentan, valsartan, olmesartan, and glyburide. If possible, an intermission of the co-administered medicinal product should be considered during the six days of treatment with tedizolid phosphate. Pharmacodynamic interactions Monoamine oxidase inhibitors Tedizolid is a reversible inhibitor of monoamine oxidase (MAO) in vitro; however, no interaction is anticipated when comparing the IC50 for MAO-A inhibition and the anticipated plasma exposures in man. Drug interaction studies to determine effects of 200 mg oral Sivextro at steady state on pseudoephedrine and tyramine pressor effects were conducted in healthy volunteers. No meaningful changes in blood pressure, heart rate with pseudoephedrine were observed in the healthy volunteers, and no clinically relevant increase in tyramine sensitivity were observed. Potential serotonergic interactions The potential for serotonergic interactions has not been studied in either patients or healthy volunteers (see section 5.2). 4.6 Fertility, pregnancy and lactation Pregnancy There are no data from the use of tedizolid phosphate in pregnant women. Studies in mice and rats showed developmental effects (see section 5.3). As a precautionary measure, it is preferable to avoid the use of tedizolid phosphate during pregnancy. Breast-feeding It is unknown whether tedizolid phosphate or its metabolites are excreted in human milk. Tedizolid is excreted in the breast milk of rats (see section 5.3). A risk to the breast-feeding infant cannot be excluded. A decision must be made whether to discontinue breast-feeding or to discontinue/abstain from Sivextro therapy taking into account the benefit of breast-feeding for the child and the benefit of therapy for the woman. Fertility The effects of tedizolid phosphate on fertility in humans have not been studied. Animal studies with tedizolid phosphate do not indicate harmful effects with respect to fertility (see section 5.3). 4.7 Effects on ability to drive and use machines No studies on the effects on the ability to drive and use machines have been performed. Sivextro may have a minor influence on the ability to drive and use machines as it may cause dizziness, fatigue or, uncommonly, somnolence (see section 4.8). 4.8 Undesirable effects Summary of the safety profile The safety of tedizolid phosphate has been evaluated in a total of 1485 subjects receiving at least one dose of tedizolid phosphate administered either orally or intravenously. The primary safety database is the Phase 3 clinical studies in which 662 subjects received 200 mg tedizolid phosphate orally and/or intravenously (331/662 patients) for a maximum of 6 days. Approximately 22.4% of patients treated with Sivextro in Phase 3 clinical studies (n=662) experienced at least one treatment-emergent adverse reaction. The most frequently reported adverse reactions occurring in patients receiving tedizolid phosphate in the pooled controlled Phase 3 clinical studies (tedizolid 200 mg once daily for 6 days) were nausea (6.9%), headache (3.5%), diarrhoea (3.2%) and vomiting (2.3%), and were generally mild to moderate in severity. Tabulated list of adverse reactions The following adverse reactions have been identified in two comparative pivotal Phase 3 studies with Sivextro (Table 1). The safety profile was similar when comparing patients receiving intravenous Sivextro alone to patients who received oral administration alone, except for a higher reported rate of gastrointestinal disorders associated with oral administration. Adverse reactions are classified by preferred term and System Organ Class, and by frequency. Frequencies are defined as: very common (≥1/10); common (≥ 1/100 to < 1/10); uncommon (≥1/1,000 to <1/100); rare (≥1/10,000 to <1/1,000); very rare (<1/10,000). Table 1 Frequency of adverse reactions by System Organ Class in pooled Phase 3 comparative clinical studies System Organ Class Common Uncommon Infections and infestations   Vulvovaginal mycotic infection Fungal infection Vulvovaginal candidiasis Abscess Clostridium difficile colitis Dermatophytosis Oral candidiasis Respiratory tract infection Blood and lymphatic system disorders   Lymphadenopathy Immune system disorders   Drug hypersensitivity Metabolism and nutrition disorders   Dehydration Diabetes mellitus inadequate control Hyperkalaemia Psychiatric disorders   Insomnia Sleep disorder Anxiety Nightmare Nervous system disorders Headache Somnolence Dizziness Dysgeusia Tremor Paraesthesia Hypoaesthesia Eye disorders   Vision blurred Vitreous floaters Cardiac disorders   Bradycardia Vascular disorders   Flushing Hot flush Respiratory, thoracic and mediastinal disorders   Cough Nasal dryness Pulmonary congestion Gastrointestinal disorders Nausea Abdominal pain Diarrhoea Constipation Vomiting Abdominal discomfort Dry mouth Dyspepsia Abdominal pain upper Flatulence Gastrooesophageal reflux disease Haematochezia Retching Skin and subcutaneous tissue disorders Pruritus Generalised Hyperhidrosis Pruritus Rash Urticaria Alopecia Rash erythematous Rash generalised Acne Pruritus allergic Rash maculo-papular Rash papular Rash pruritic Musculoskeletal and connective tissue disorders   Arthralgia Muscle spasms Back pain Limb discomfort Neck pain Renal and urinary disorders   Urine odor abnormal Reproductive and breast disorders   Vulvovaginal pruritus General disorders and administration site conditions Fatigue Chills Infusion site pain Infusion site phlebitis Irritability Pyrexia Infusion related reaction Peripheral oedema Investigations   Grip strength decreased   Transaminases increased White blood cell count decreased Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme, at www.mhra.gov.uk/yellowcard. 4.9 Overdose In the event of overdose, Sivextro should be discontinued and general supportive treatment given. Hemodialysis does not result in meaningful removal of tedizolid from systemic circulation. The highest single dose administered in clinical studies was 1,200 mg. All adverse reactions at this dose level were mild or moderate in severity. 5. Pharmacological properties 5.1 Pharmacodynamic properties Pharmacotherapeutic group: not yet assigned, ATC code: not yet assigned Mechanism of action Tedizolid phosphate is an oxazolidinone phosphate prodrug. The antibacterial activity of tedizolid is mediated by binding to the 50S subunit of the bacterial ribosome resulting in inhibition of protein synthesis. Tedizolid is primarily active against Gram-positive bacteria. Tedizolid is bacteriostatic against enterococci, staphylococci, and streptococci in vitro. Resistance The most commonly observed mutations in staphylococci and enterococci that result in oxazolidinone resistance are in one or more copies of the 23S rRNA genes (G2576U and T2500A). Organisms resistant to oxazolidinones via mutations in chromosomal genes encoding 23S rRNA or ribosomal proteins (L3 and L4) are generally cross-resistant to tedizolid. A second resistance mechanism is encoded by a plasmid-borne and transposon associated chloramphenicol-florfenicol resistance (cfr) gene, conferring resistance in staphylococci and enterococci to oxazolidinones, phenicols, lincosamides, pleuromutilins, streptogramin A and 16-membered macrolides. Due to a hydroxymethyl group in the C5 position, tedizolid retains activity against strains of Staphylococcus aureus that express the cfr gene in the absence of chromosomal mutations. The mechanism of action is different from that of non-oxazolidinone class antibacterial medicinal products; therefore, cross-resistance between tedizolid and other classes of antibacterial medicinal products is unlikely. Antibacterial activity in combination with other antibacterial and antifungal agents In vitro drug combination studies with tedizolid and amphotericin B, aztreonam, ceftazidime, ceftriaxone, ciprofloxacin, clindamycin, colistin, daptomycin, gentamicin, imipenem, ketoconazole, minocycline, piperacillin, rifampicin, terbinafine, trimethoprim/sulfamethoxazole, and vancomycinindicate that neither synergy nor antagonism have been demonstrated. Susceptibility testing breakpoints Minimum inhibitory concentration (MIC) breakpoints determined by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) are: Organisms Minimum Inhibitory Concentrations (mg/L) Susceptible (≤S) Resistant (R>) Staphylococcus spp. 0.5 0.5 Beta haemolytic Streptococci of Groups A,B,C,G 0.5 0.5 Viridans group streptococci (Streptococcus anginosus group only) 0.25 0.25 Pharmacokinetic/pharmacodynamic relationship The AUC/MIC ratio was the pharmacodynamic parameter shown to best correlate with efficacy in mouse thigh and lung S. aureus infection models. In a mouse thigh infection model of S. aureus, the antibacterial activity of tedizolid was reduced in the absence of granulocytes. The AUC/MIC ratio to achieve bacteriostasis in neutropenic mice was at least 16 times that in immunocompetent animals (see section 4.4). Clinical efficacy against specific pathogens Efficacy has been demonstrated in clinical studies against the pathogens listed under each indication that were susceptible to tedizolid in vitro. Acute bacterial skin and skin structure infections • Staphylococcus aureus • Streptococcus pyogenes • Streptococcus agalactiae • Streptococcus anginosus group (including S. anginosus, S. intermedius and S. constellatus) Antibacterial activity against other relevant pathogens Clinical efficacy has not been established against the following pathogens although in vitro studies suggest that they would be susceptible to tedizolid in the absence of acquired mechanisms of resistance: • Staphylococcus lugdunensis Paediatric population The European Medicines Agency has deferred the obligation to submit the results of studies with Sivextro in one or more subsets of the paediatric population in the treatment of acute bacterial skin and skin structure infections (see section 4.2 for information on paediatric use). 5.2 Pharmacokinetic properties Oral and intravenous tedizolid phosphate is a prodrug that is rapidly converted by phosphatases to tedizolid, the microbiologically active moiety. Only the pharmacokinetic profile of tedizolid is discussed in this section. Pharmacokinetic studies were conducted in healthy volunteers and population pharmacokinetic analyses were conducted in patients from Phase 3 studies. Absorption At steady state, tedizolid mean (SD) Cmax values of 2.2 (0.6) and 3.0 (0.7) mcg/mL and AUC values of 25.6 (8.5) and 29.2 (6.2) mcg·h/mL were similar with oral and IV administration of tedizolid phosphate, respectively. The absolute bioavailability of tedizolid is above 90%. Peak plasma tedizolid concentrations are achieved within approximately 3 hours after dosing after oral administration of Sivextro under fasted conditions. Peak concentrations (Cmax) of tedizolid are reduced by approximately 26% and delayed by 6 hours when tedizolid phosphate is administered after a high-fat meal relative to fasted, while total exposure (AUC0-∞) is unchanged between fasted and fed conditions. Distribution The average binding of tedizolid to human plasma proteins is approximately 70-90%. The mean steady state volume of distribution of tedizolid in healthy adults (n=8) following a single intravenous dose of tedizolid phosphate 200 mg ranged from 67 to 80 L. Biotransformation Tedizolid phosphate is converted by endogenous plasma and tissue phosphatases to the microbiologically active moiety, tedizolid. Other than tedizolid, which accounts for approximately 95% of the total radiocarbon AUC in plasma, there are no other significant circulating metabolites. When incubated with pooled human liver microsomes, tedizolid was stable suggesting that tedizolid is not a substrate for hepatic CYP450 enzymes. Multiple sulfotransferase (SULT) enzymes (SULT1A1, SULT1A2, and SULT2A1) are involved in the biotransformation of tedizolid, to form an inactive and non-circulating sulphate conjugate found in the excreta. Elimination Tedizolid is eliminated in excreta, primarily as a non-circulating sulfate conjugate. Following single oral administration of 14C-labeled Sivextro under fasted conditions, the majority of elimination occurred via the liver with 81.5% of the radioactive dose recovered in faeces and 18% in urine, with most of the elimination (>85%) occurring within 96 hours. Less than 3% of Sivextro administered dose is excreted as active tedizolid. The elimination half-life of tedizolid is approximately 12 hours and the intravenous clearance is 6-7 L/h. Linearity/non-linearity Tedizolid demonstrated linear pharmacokinetics with regard to dose and time. The Cmax and AUC of tedizolid increased approximately dose proportionally within the single oral dose range of 200 mg to 1200 mg and across the intravenous dose range of 100 mg to 400 mg. Steady-state concentrations are achieved within 3 days and indicate modest active substance accumulation of approximately 30% following multiple once-daily oral or intravenous administration as predicted by a half-life of approximately 12 hours. Special populations Renal impairment Following administration of a single 200 mg IV dose of Sivextro to 8 subjects with severe renal impairment defined as eGFR <30 mL/min, the Cmax was basically unchanged and AUC0-∞ was changed by less than 10% compared to 8 matched healthy subject controls. Hemodialysis does not result in meaningful removal of tedizolid from systemic circulation, as assessed in subjects with end-stage renal disease (eGFR <15 mL/min). The eGFR was calculated using the MDRD4 equation. Hepatic Impairment Following administration of a single 200 mg oral dose of Sivextro, the pharmacokinetics of tedizolid are not altered in patients with moderate (n=8) or severe (n=8) hepatic impairment (Child-Pugh Class B and C). Elderly population (≥ 65 years) The pharmacokinetics of tedizolid in elderly healthy volunteers (age 65 years and older, with at least 5 subjects at least 75 years old; n=14) was comparable to younger control subjects (25 to 45 years old; n=14) following administration of a single oral dose of Sivextro 200 mg. Paediatric population The pharmacokinetics of tedizolid were evaluated in adolescent subjects (12 to 17 years; n=20) following administration of a single oral or IV dose of Sivextro 200 mg. The mean Cmax and AUC0-∞ for oral or IV administration of tedizolid 200 mg were similar in adolescent and in healthy adult subjects. Gender The impact of gender on the pharmacokinetics of Sivextro was evaluated in healthy males and females in clinical studies and in a population pharmacokinetics analysis. The pharmacokinetics of tedizolid were similar in males and females. Drug interaction studies Drug metabolizing enzymes In vitro studies in human liver microsomes indicate that tedizolid phosphate and tedizolid do not significantly inhibit metabolism mediated by any of the following cytochrome P450 isoenzymes (CYP1A2, CYP2C19, CYP2A6, CYP2C8, CYP2C9, CYP2D6, and CYP3A4). Induction of CYP3A4 mRNA was observed in vitro in hepatocytes (see section 4.5). Multiple sulfotransferases (SULT) isoforms were identified in vitro that are capable of conjugating tedizolid (spanning multiple families; SULT1A1, SULT1A2, and SULT2A1), which suggests that no single isozyme is critical to the clearance of tedizolid. Membrane transporters The potential for tedizolid or tedizolid phosphate to inhibit transport of probe substrates of important drug uptake (OAT1, OAT3, OATP1B1, OATP1B3, OCT1, and OCT2) and efflux transporters (P-gp and BCRP) was tested in vitro. No consistent inhibition of any transporter was observed with the exception of BCRP, which was inhibited by tedizolid. Tedizolid inhibited OATP1B1 by ~30% at 30 µM. Monoamine oxidase inhibition Tedizolid is a reversible inhibitor of MAO in vitro; however, no interaction is anticipated when comparing the IC50 and the anticipated plasma exposures in man. No evidence of MAO-A inhibition was observed in Phase 1 studies specifically designed to investigate the potential for this interaction. Adrenergic agents Two placebo-controlled crossover studies were conducted to assess the potential of 200 mg oral tedizolid phosphate at steady state to enhance pressor responses to pseudoephedrine and tyramine in healthy individuals. No meaningful changes in blood pressure or heart rate were seen with pseudoephedrine. The median tyramine dose required to cause an increase in systolic blood pressure of ≥30 mmHg from pre-dose baseline was 325 mg with Sivextro compared to 425 mg with placebo. Administration of Sivextro with tyramine-rich foods (i.e., containing tyramine levels of approximately 100 mg) would not be expected to elicit a pressor response. Serotonergic agents Serotonergic effects at doses of tedizolid phosphate up to 30-fold above the human equivalent dose did not differ from vehicle control in a mouse model that predicts brain serotonergic activity. There are limited data in patients on the interaction between serotonergic agents and tedizolid phosphate. In Phase 3 studies, subjects taking serotonergic agents including antidepressants such as selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, and serotonin 5-hydroxytryptamine (5-HT1) receptor agonists (triptans), meperidine, or buspirone were excluded. 5.3 Preclinical safety data Long-term carcinogenicity studies have not been conducted with tedizolid phosphate. Repeated oral and intravenous dosing of tedizolid phosphate in rats in 1-month and 3-month toxicology studies produced dose- and time-dependent bone marrow hypocellularity (myeloid, erythroid, and megakaryocyte), with associated reduction in circulating RBCs, WBCs, and platelets. These effects showed evidence of reversibility and occurred at plasma tedizolid exposure levels (AUC) ≥6-fold greater than the plasma exposure associated with the human therapeutic dose. In a 1-month immunotoxicology study in rats, repeated oral dosing of tedizolid phosphate was shown to significantly reduce splenic B cells and T cells and reduce plasma IgG titers. These effects occurred at plasma tedizolid exposure levels (AUC) ≥3-fold greater than the expected human plasma exposure associated with the therapeutic dose. A special neuropathology study was conducted in pigmented Long Evans rats administered tedizolid phosphate daily for up to 9 months. This study used sensitive morphologic evaluation of perfusion-fixed peripheral and central nervous system tissue. No evidence of neurotoxicity, including neurobehavioral changes or optic or peripheral neuropathy, was associated with tedizolid after 1, 3, 6 or 9 months of oral administration up to doses with plasma exposure levels (AUC) up to 8-fold greater than the expected human plasma exposure at the oral therapeutic dose. Tedizolid phosphate was negative for genotoxicity in all in vitro assays (bacterial reverse mutation [Ames], Chinese hamster lung [CHL] cell chromosomal aberration) and in all in vivo tests (mouse bone marrow micronucleus, rat liver unscheduled DNA synthesis). Tedizolid, generated from tedizolid phosphate after metabolic activation (in vitro and in vivo), was also tested for genotoxicity. Tedizolid was positive in an in vitro CHL cell chromosomal aberration assay, but negative for genotoxicity in other in vitro assays (Ames, mouse lymphoma mutagenicity) and in vivo in a mouse bone marrow micronucleus assay. Tedizolid had no adverse effects on the fertility or reproductive performance of male rats, including spermatogenesis, at oral doses up to the maximum tested dose of 50 mg/kg/day, or adult female rats at oral doses up to the maximum tested dose of 15 mg/kg/day. These dose levels equate to exposure margins of ≥ 5.3-fold for males and ≥ 4.2-fold for females relative to tedizolid plasma AUC0-24 levels at the human oral therapeutic dose. Embryo-foetal development studies in mice and rats showed no evidence of a teratogenic effect at exposure levels 4-fold and 6-fold, respectively, those expected in humans. In embryo-foetal studies, tedizolid phosphate was shown to produce foetal developmental toxicities in mice and rats. Foetal developmental effects occurring in mice in the absence of maternal toxicity included reduced foetal weights and an increased incidence of costal cartilage fusion (an exacerbation of the normal genetic predisposition to sternal variations in the CD-1 strain of mice) at the high dose of 25 mg/kg/day (4-fold the estimated human exposure level based on AUCs). In rats, decreased foetal weights and increased skeletal variations including reduced ossification of the sternabrae, vertebrae, and skull were observed at the high dose of 15 mg/kg/day (6-fold the estimated human exposure based on AUCs) and were associated with maternal toxicity (reduced maternal body weights). The no observed adverse effect levels (NOAELs) for foetal toxicity in mice (5 mg/kg/day) as well as maternal and foetal toxicity in rats (2.5 mg/kg/day) were associated with tedizolid plasma area under the curve (AUC) values approximately equivalent to the tedizolid AUC value associated with the oral human therapeutic dose. Tedizolid is excreted into the milk of lactating rats and the concentrations observed similar to those in maternal plasma. 6. Pharmaceutical particulars 6.1 List of excipients Mannitol Sodium hydroxide (for pH adjustment) Hydrochloric acid (for pH adjustment) 6.2 Incompatibilities This medicinal product must not be mixed with other medicinal products except those mentioned in section 6.6. Sivextro is incompatible with any solutions containing divalent cations (e.g., Ca2+, Mg2+), including Lactated Ringer's Injection and Hartmann's Solution. 6.3 Shelf life 3 years. After reconstitution, it should be used within 4 hours at room temperature or 24 hours when stored at 2°C to 8°C. 6.4 Special precautions for storage This medicinal product does not require any special storage conditions. For storage conditions after reconstitution and dilution of the medicinal product, see section 6.3. 6.5 Nature and contents of container Type I (10 ml) clear borosilicate tubing glass vial with a siliconised grey chlorobutyl rubber stopper. Available in packs of 1 vial and 6 vials. Not all pack sizes may be marketed. 6.6 Special precautions for disposal and other handling Sivextro vials are intended for single use only. It must be administered as an intravenous infusion only. It must not be administered as an intravenous bolus. Aseptic technique must be followed in preparing the infusion solution. The contents of Sivextro should be reconstituted with 4 ml of water for injections, and be swirled gently until the powder has dissolved entirely. Shaking or rapid movement should be avoided as it may cause foaming. For administration, the reconstituted solution must be further diluted in 250 ml of sodium chloride 0.9% solution for injection. The bag should not be shaken. The resulting solution is a clear colourless or light-yellow solution and should be administered over approximately 1 hour. Only limited data are available on the compatibility of Sivextro with other intravenous substances, therefore additives or other medicinal products should not be added to Sivextro single use vials or infused simultaneously. If the same intravenous line is used for sequential infusion of several different medicinal products, the line should be flushed before and after infusion with 0.9% sodium chloride. The reconstituted solution should be inspected visually for particulate matter prior to administration. Reconstituted solutions containing visible particles should be discarded. Any unused medicinal product or waste material should be disposed of in accordance with local requirements. 7. Marketing authorisation holder Cubist (UK) Ltd Unit 1 Horizon Business Village No 1, Brooklands Road Weybridge Surrey KT13 0RU United Kingdom 8. Marketing authorisation number(s) EU/1/15/991/002 EU/1/15/991/003 9. Date of first authorisation/renewal of the authorisation 25 March 2015 10. Date of revision of the text Detailed information on this medicinal product is available on the website of the European Medicines Agency http://www.ema.europa.eu. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm402174.htm 美国FDA批准Sivextro治疗皮肤感染 2014年6月20日美国食品药品监督管理局(FDA)批准Sivextro(tedizolid phosphate)，一种新抗细菌药，治疗成年有皮肤感染。 Sivextro被批准治疗由某些易感细菌所致有急性细菌性皮肤和皮肤结构感染(ABSSSI)患者，包括金黄色葡萄球菌[Staphylococcus aureus](包括耐甲氧西林菌株[methicillin-resistant strains] (MRSA)和甲氧西林敏感菌株[methicillin-susceptible strains])，各种链球菌属[Streptococcus species]，和粪肠球菌[Enterococcus faecalis]。可得到为静脉和口服使用的Sivextro。 Sivextro是过去一个月中被FDA批准的第二个治疗ABSSSI的新抗细菌药。在201年5月23日，监管局批准Dalvance (达巴万星[dalbavancin])，也治疗被金黄色葡萄球菌和各种链球菌属所致有ABSSSI患者。 FDA药品评价和研究中心的抗微生物产品室主任Edward Cox，M.D.，M.P.H说：“今天的批准提供医生和患者对严重有皮肤感染一种新治疗选择，” 对Sivextro应用，意向治疗严重或危及生命感染，被指定为一种合格的传染病产品(QIDP)和接受一种加快审评。Sivextro的QIDP指定还使它合格对另外五年专卖权将被添加至早已由食品，药品和化妆品法提供的某种专卖期。 在两项临床试验有1,315例成年有ABSSSI.参加者被随机赋予接受Sivextro或利奈唑胺[linezolid]，另一种抗细菌药被批准治疗ABSSSI评价Sivextro的安全性和疗效。结果显示为治疗ABSSSI Sivextro是与利奈唑胺一样有效。 在临床试验中被鉴定最常见副作用是恶心，头痛，腹泻，呕吐和眩晕。尚未在有白细胞水平减低(粒细胞减少) 患者中评价Sivextro的安全性和疗效，所以应考虑另外治疗。 Sivextro是由总部位于马萨诸塞州莱克星顿的Cubist药业上市。