Components:
Method of action:
Treatment option:
Medically reviewed by Oliinyk Elizabeth Ivanovna, PharmD. Last updated on 03.04.2022
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Megaxin is indicated for the treatment of:
- Community acquired pneumonia (CAP)
- Complicated skin and skin structure infections (cSSSI)
Moxifloxacin should be used only when it is considered inappropriate to use antibacterial agents that are commonly recommended for the initial treatment of these infections.
Consideration should be given to official guidance on the appropriate use of antibacterial agents.
Megaxin® solution is indicated for the treatment of bacterial conjunctivitis caused by susceptible strains of the following organisms:
Corynebacterium species*
Micrococcus luteus*
Staphylococcus aureus
Staphylococcus epidermidis
Staphylococcus haemolyticus
Staphylococcus hominis
Staphylococcus warneri*
Streptococcus pneumoniae
Streptococcus viridans group
Acinetobacter lwoffii*
Haemophilus influenzae
Haemophilus parainfluenzae*
Chlamydia trachomatis
*Efficacy for this organism was studied in fewer than 10 infections.
Posology
The recommended dose is 400 mg moxifloxacin, infused once daily.
Initial intravenous treatment may be followed by oral treatment with moxifloxacin 400 mg tablets, when clinically indicated.
In clinical studies most patients switched to oral therapy within 4 days (CAP) or 6 days (cSSSI). The recommended total duration of intravenous and oral treatment is 7 - 14 days for CAP and 7 - 21 days for cSSSI.
Renal/hepatic impairment
No adjustment of dosage is required in patients with mild to severely impaired renal function or in patients on chronic dialysis i.e. haemodialysis and continuous ambulatory peritoneal dialysis.
There is insufficient data in patients with impaired liver function.
Other special populations
No adjustment of dosage is required in the elderly and in patients with low bodyweight.
Paediatric population
Moxifloxacin is contraindicated in children and growing adolescents. Efficacy and safety of moxifloxacin in children and adolescents have not been established.
Method of administration
If medically indicated the solution for infusion can be administered via a T-tube, together with compatible infusion solutions.
Instill one drop in the affected eye 3 times a day for 7 days.
- Pregnancy and lactation.
- Patients below 18 years of age.
- Patients with a history of tendon disease/disorder related to quinolone treatment.
Both in preclinical investigations and in humans, changes in cardiac electrophysiology have been observed following exposure to moxifloxacin, in the form of QT prolongation.).
Due to limited clinical data, moxifloxacin is also contraindicated in patients with impaired liver function (Child Pugh C) and in patients with transaminases increase > 5fold ULN.
Megaxin® solution is contraindicated in patients with a history of hypersensitivity to moxifloxacin, to other quinolones, or to any of the components in this medication.
The benefit of moxifloxacin treatment especially in infections with a low degree of severity should be balanced with the information contained in the warnings and precautions section.
Prolongation of QTc interval and potentially QTc-prolongation-related clinical conditions
| Moxifloxacin has been shown to prolong the QTc interval on the electrocardiogram in some patients.5. |
Treatment with moxifloxacin should be stopped if signs or symptoms that may be associated with cardiac arrhythmia occur during treatment, with or without ECG findings.
Moxifloxacin should be used with caution in patients with any condition pre-disposing to cardiac arrhythmias (e.g. acute myocardial ischaemia) because they may have an increased risk of developing ventricular arrhythmias (incl. torsade de pointes) and cardiac arrest.5.
Moxifloxacin should be used with caution in patients who are taking medications that can reduce potassium levels.5.
Moxifloxacin should be used with caution in patients who are taking medications associated with clinically significant bradycardia.
Female patients and elderly patients may be more sensitive to the effects of QTc-prolonging medications such as moxifloxacin and therefore special caution is required.
Hypersensitivity/allergic reactions
Hypersensitivity and allergic reactions have been reported for fluoroquinolones including moxifloxacin after first administration. Anaphylactic reactions can progress to a life-threatening shock, even after the first administration. In cases of clinical manifestations of severe hypersensitivity reactions moxifloxacin should be discontinued and suitable treatment (e.g. treatment for shock) initiated.
Severe liver disorders
Cases of fulminant hepatitis potentially leading to liver failure (including fatal cases) have been reported with moxifloxacin. Patients should be advised to contact their doctor prior to continuing treatment if signs and symptoms of fulminant hepatic disease develop such as rapidly developing asthenia associated with jaundice, dark urine, bleeding tendency or hepatic encephalopathy.
Liver function tests/investigations should be performed in cases where indications of liver dysfunction occur.
Serious bullous skin reactions
Cases of bullous skin reactions like Stevens-Johnson syndrome or toxic epidermal necrolysis have been reported with moxifloxacin. Patients should be advised to contact their doctor immediately prior to continuing treatment if skin and/or mucosal reactions occur.
Patients predisposed to seizures
Quinolones are known to trigger seizures. Use should be with caution in patients with CNS disorders or in the presence of other risk factors which may predispose to seizures or lower the seizure threshold. In case of seizures, treatment with moxifloxacin should be discontinued and appropriate measures instituted.
Peripheral neuropathy
Cases of sensory or sensorimotor polyneuropathy resulting in paraesthesias, hypoaesthesias, dysaesthesias, or weakness have been reported in patients receiving quinolones including moxifloxacin. Patients under treatment with moxifloxacin should be advised to inform their doctor prior to continuing treatment if symptoms of neuropathy such as pain, burning, tingling, numbness, or weakness develop in order to prevent the development of an irreversible condition.
Psychiatric reactions
Psychiatric reactions may occur even after the first administration of quinolones, including moxifloxacin. In very rare cases depression or psychotic reactions have progressed to suicidal thoughts and self-injurious behaviour such as suicide attempts. In the event that the patient develops these reactions, moxifloxacin should be discontinued and appropriate measures instituted. Caution is recommended if moxifloxacin is to be used in psychotic patients or in patients with history of psychiatric disease.
Antibiotic-associated diarrhoea incl. colitis
Antibiotic-associated diarrhoea (AAD) and antibiotic-associated colitis (AAC), including pseudomembranous colitis and Clostridium difficile-associated diarrhoea, has been reported in association with the use of broad spectrum antibiotics including moxifloxacin and may range in severity from mild diarrhoea to fatal colitis. Therefore it is important to consider this diagnosis in patients who develop serious diarrhoea during or after the use of moxifloxacin. If AAD or AAC is suspected or confirmed, ongoing treatment with antibacterial agents, including moxifloxacin, should be discontinued and adequate therapeutic measures should be initiated immediately. Furthermore, appropriate infection control measures should be undertaken to reduce the risk of transmission. Drugs inhibiting peristalsis are contraindicated in patients who develop serious diarrhoea.
Patients with myasthenia gravis
Moxifloxacin should be used with caution in patients with myasthenia gravis because the symptoms can be exacerbated.
Tendon inflammation, tendon rupture
Tendon inflammation and rupture (especially Achilles tendon), sometimes bilateral, may occur with quinolone therapy including moxifloxacin, even within 48 hours of starting treatment and have been reported up to several months after discontinuation of therapy. The risk of tendinitis and tendon rupture is increased in elderly patients and in those treated concurrently with corticosteroids. At the first sign of pain or inflammation, patients should discontinue treatment with moxifloxacin, rest the affected limb(s) and consult their doctor immediately in order to initiate appropriate treatment (e.g. immobilisation) for the affected tendon.
Patients with renal impairment
Elderly patients with renal disorders should use moxifloxacin with caution if they are unable to maintain adequate fluid intake, because dehydration may increase the risk of renal failure.
Vision disorders
If vision becomes impaired or any effects on the eyes are experienced, an eye specialist should be consulted immediately.
Dysglycemia
As with all fluoroquinolones, disturbances in blood glucose, including both hypoglycemia and hyperglycemia have been reported with moxifloxacin. In moxifloxacin-treated patients, dysglycemia occurred predominantly in elderly diabetic patients receiving concomitant treatment with an oral hypoglycemic agent (e.g. sulfonylurea) or with insulin. In diabetic patients, careful monitoring of blood glucose is recommended.
Prevention of photosensitivity reactions
Quinolones have been shown to cause photosensitivity reactions in patients. However, studies have shown that moxifloxacin has a lower risk to induce photosensitivity. Nevertheless patients should be advised to avoid exposure to either UV irradiation or extensive and/or strong sunlight during treatment with moxifloxacin.
Patients with glucose-6-phosphate dehydrogenase deficiency
Patients with a family history of or actual glucose-6-phosphate dehydrogenase deficiency are prone to haemolytic reactions when treated with quinolones. Therefore, moxifloxacin should be used with caution in these patients.
Peri-arterial tissue inflammation
Moxifloxacin solution for infusion is for intravenous administration only. Intra-arterial administration should be avoided since preclinical studies demonstrated peri-arterial tissue inflammation following infusion by this route.
Patients with special cSSSI
Clinical efficacy of moxifloxacin in the treatment of severe burn infections, fasciitis and diabetic foot infections with osteomyelitis has not been established.
Patients on sodium diet
This medicinal product contains 787 mg (approximately 34 mmol) sodium per dose. To be taken into consideration by patients on a controlled sodium diet.
Interference with biological tests
Moxifloxacin therapy may interfere with the Mycobacterium spp. culture test by suppression of mycobacterial growth causing false negative results in samples taken from patients currently receiving moxifloxacin.
Patients with MRSA infections
Moxifloxacin is not recommended for the treatment of MRSA infections. In case of a suspected or confirmed infection due to MRSA, treatment with an appropriate antibacterial agent should be started.
Paediatric population
Due to adverse effects on the cartilage in juvenile animals the use of moxifloxacin in children and adolescents < 18 years is contraindicated.
WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
Topical Ophthalmic Use Only
NOT FOR INJECTION. Megaxin® solution is for topical ophthalmic use only and should not be injected subconjunctivally or introduced directly into the anterior chamber of the eye.
Hypersensitivity Reaction
In patients receiving systemically administered quinolones, including moxifloxacin, serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported, some following the first dose. Some reactions were accompanied by cardiovascular collapse, loss of consciousness, angioedema (including laryngeal, pharyngeal or facial edema), airway obstruction, dyspnea, urticaria, and itching. If an allergic reaction to moxifloxacin occurs, discontinue use of the drug. Serious acute hypersensitivity reactions may require immediate emergency treatment. Oxygen and airway management should be administered as clinically indicated.
Growth Of Resistant Organisms With Prolonged Use
As with other anti-infectives, prolonged use may result in overgrowth of non-susceptible organisms, including fungi. If superinfection occurs, discontinue use and institute alternative therapy. Whenever clinical judgment dictates, the patient should be examined with the aid of magnification, such as slit-lamp biomicroscopy, and, where appropriate, fluorescein staining.
Avoidance Of Contact Lens Wear
Patients should be advised not to wear contact lenses if they have signs or symptoms of bacterial conjunctivitis.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Long-term studies in animals to determine the carcinogenic potential of moxifloxacin have not been performed. However, in an accelerated study with initiators and promoters, moxifloxacin was not carcinogenic in rats following up to 38 weeks of oral dosing at 500 mg/kg/day (approximately 21,700 times the highest recommended total daily human ophthalmic dose for a 50 kg person, on a mg/kg basis).
Moxifloxacin was not mutagenic in four bacterial strains used in the Ames Salmonella reversion assay. As with other quinolones, the positive response observed with moxifloxacin in strain TA 102 using the same assay may be due to the inhibition of DNA gyrase. Moxifloxacin was not mutagenic in the CHO/HGPRT mammalian cell gene mutation assay. An equivocal result was obtained in the same assay when v79 cells were used. Moxifloxacin was clastogenic in the v79 chromosome aberration assay, but it did not induce unscheduled DNA synthesis in cultured rat hepatocytes. There was no evidence of genotoxicity in vivo in a micronucleus test or a dominant lethal test in mice.
Moxifloxacin had no effect on fertility in male and female rats at oral doses as high as 500 mg/kg/day, approximately 21,700 times the highest recommended total daily human ophthalmic dose. At 500 mg/kg orally there were slight effects on sperm morphology (head-tail separation) in male rats and on the estrous cycle in female rats.
Use In Specific Populations
Pregnancy
Pregnancy Category C.
Teratogenic Effects
Moxifloxacin was not teratogenic when administered to pregnant rats during organogenesis at oral doses as high as 500 mg/kg/day (approximately 21,700 times the highest recommended total daily human ophthalmic dose); however, decreased fetal body weights and slightly delayed fetal skeletal development were observed. There was no evidence of teratogenicity when pregnant Cynomolgus monkeys were given oral doses as high as 100 mg/kg/day (approximately 4,300 times the highest recommended total daily human ophthalmic dose). An increased incidence of smaller fetuses was observed at 100 mg/kg/day.
Since there are no adequate and well-controlled studies in pregnant women, Megaxin® solution should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Nursing Mothers
Moxifloxacin has not been measured in human milk, although it can be presumed to be excreted in human milk. Caution should be exercised when Megaxin® solution is administered to a nursing mother.
Pediatric Use
The safety and effectiveness of Megaxin® solution in infants below 1 year of age have not been established.
There is no evidence that the ophthalmic administration of Megaxin® solution has any effect on weight bearing joints, even though oral administration of some quinolones has been shown to cause arthropathy in immature animals.
Geriatric Use
No overall differences in safety and effectiveness have been observed between elderly and younger patients.
No studies on the effects of moxifloxacin on the ability to drive and use machines have been performed. However, fluoroquinolones including moxifloxacin may result in an impairment of the patient's ability to drive or operate machinery due to CNS reactions or acute and short lasting loss of consciousness. Patients should be advised to see how they react to moxifloxacin before driving or operating machinery.
Adverse reactions observed in clinical trials and derived from post-marketing reports with moxifloxacin 400 mg daily administered by the intravenous or oral route (intravenous only, sequential [IV/oral] and oral administration) sorted by frequencies are listed below:
Apart from nausea and diarrhoea all adverse reactions were observed at frequencies below 3%.
Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness. Frequencies are defined as:
- 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)
| System Organ Class (MedDRA) | Common | Uncommon | Rare | Very Rare |
| Infections and infestations | Superinfections due to resistant bacteria or fungi e.g. oral and vaginal candidiasis | |||
| Blood and lymphatic system disorders | Anaemia Leucopenia(s) Neutropenia Thrombocytopenia Thrombocythemia Blood eosinophilia Prothrombin time prolonged/ INR increased | Prothrombin level increased/ INR decreased Agranulocytosis | ||
| Immune system disorders | Allergic reaction | Anaphylaxis incl. very rarely life-threatening shock Allergic oedema/ angiooedema | ||
| Metabolism and nutrition disorders | Hyperlipidemia | Hyperglycemia Hyperuricemia | Hypoglycemia | |
| Psychiatric disorders | Anxiety reactions Psychomotor hyperactivity/ agitation | Emotional lability Depression Hallucination | Depersonalization Psychotic reactions | |
| Nervous system disorders | Headache Dizziness | Par- and Dysaesthesia Taste disorders (incl. ageusia in very rare cases) Confusion and disorientation Sleep disorders (predominantly insomnia) Tremor Vertigo Somnolence | Hypoaesthesia Smell disorders (incl. anosmia) Abnormal dreams Disturbed coordination (incl. gait disturbances, esp. due to dizziness or vertigo) Seizures incl. grand mal convulsions Disturbed attention Speech disorders Amnesia Peripheral neuropathy and polyneuropathy | Hyperaesthesia |
| Eye disorders | Visual disturbances incl. diplopia and blurred vision | Transient loss of vision | ||
| Ear and labyrinth disorders | Tinnitus Hearing impairment incl. deafness (usually reversible) | |||
| Cardiac disorders | QT prolongation in patients with hypokalaemia | QT prolongation Palpitations Tachycardia Atrial fibrillation Angina pectoris | Ventricular tachyarrhythmias Syncope (i.e., acute and short lasting loss of consciousness) | Unspecified arrhythmias Torsade de Pointes Cardiac arrest |
| Vascular disorders | Vasodilatation | Hypertension Hypotension | Vasculitis | |
| Respiratory, thoracic and mediastinal disorders | Dyspnea (including asthmatic conditions) | |||
| Gastrointestinal disorders | Nausea Vomiting Gastrointestinal and abdominal pains Diarrhoea | Decreased appetite and food intake Constipation Dyspepsia Flatulence Gastritis Increased amylase | Dysphagia Stomatitis Antibiotic-associated colitis | |
| Hepatobiliary disorders | Increase in transaminases | Hepatic impairment (incl. LDH increase) Increased bilirubin Increased gamma-glutamyl-transferase Increase in blood alkaline phosphatase | Jaundice Hepatitis (predominantly cholestatic) | Fulminant hepatitis potentially leading to life-threatening liver failure |
| Skin and subcutaneous tissue disorders | Pruritus Rash Urticaria Dry skin | Bullous skin reactions like Stevens-Johnson syndrome or toxic epidermal necrolysis | ||
| Musculoskeletal andconnective tissue disorders | Arthralgia Myalgia | Tendonitis Muscle cramp Muscle twitching Muscle weakness | Tendon rupture Arthritis Muscle rigidity Exacerbation of symptoms of myasthenia gravis | |
| Renal and urinary disorders | Dehydration | Renal impairment (incl. increase in BUN and creatinine) Renal failure | ||
| General disorders and administration site conditions | Injection and infusion site reactions | Feeling unwell (predominantly asthenia or fatigue) Painful conditions (incl. pain in back, chest, pelvic and extremities) Sweating Infusion site (thrombo-) phlebitis | Oedema |
The following undesirable effects have a higher frequency category in the subgroup of IV treated patients with or without subsequent oral therapy:
| Common: | Increased gamma-glutamyl-transferase |
| Uncommon: | Ventricular tachyarrhythmias, hypotension, oedema, antibiotic-associated colitis , seizures incl. grand mal convulsions , hallucination, renal impairment (incl. increase in BUN and creatinine), renal failure |
There have been very rare cases of the following side effects reported following treatment with other fluoroquinolones, which might possibly also occur during treatment with moxifloxacin: hypernatraemia, hypercalcaemia, haemolytic anaemia, rhabdomyolysis, photosensitivity reactions..
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, Website: www.mhra.gov.uk/yellowcard.
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to the rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The most frequently reported ocular adverse events were conjunctivitis, decreased visual acuity, dry eye, keratitis, ocular discomfort, ocular hyperemia, ocular pain, ocular pruritus, subconjunctival hemorrhage, and tearing. These events occurred in approximately 1-6% of patients.
Nonocular adverse events reported at a rate of 1-4% were fever, increased cough, infection, otitis media, pharyngitis, rash, and rhinitis.
No specific countermeasures after accidental overdose are recommended. In the event of overdose, symptomatic treatment should be implemented. ECG monitoring should be undertaken, because of the possibility of QT interval prolongation. Concomitant administration of charcoal with a dose of 400 mg oral or intravenous moxifloxacin will reduce systemic availability of the drug by more than 80% or 20% respectively. The use of charcoal early during absorption may be useful to prevent excessive increase in the systemic exposure to moxifloxacin in cases of oral overdose.
No information provided.
Pharmacotherapeutic group: Quinolone antibacterials, fluoroquinolones, ATC code: J01MA14
Mechanism of action
Moxifloxacin inhibits bacterial type II topoisomerases (DNA gyrase and topoisomerase IV) that are required for bacterial DNA replication, transcription and repair.
PK/PD
Fluoroquinolones exhibit a concentration dependent killing of bacteria. Pharmacodynamic studies of fluoroquinolones in animal infection models and in human trials indicate that the primary determinant of efficacy is the AUC24/MIC ratio.
Mechanism of resistance
Resistance to fluoroquinolones can arise through mutations in DNA gyrase and topoisomerase IV. Other mechanisms may include over-expression of efflux pumps, impermeability, and protein-mediated protection of DNA gyrase. Cross resistance should be expected between moxifloxacin and other fluoroquinolones.
The activity of moxifloxacin is not affected by mechanisms of resistance that are specific to antibacterial agents of other classes.
Breakpoints
EUCAST clinical MIC and disk diffusion breakpoints for moxifloxacin (01.01.2011):
| Organism | Susceptible | Resistant |
| Staphylococcus spp. | ≤ 0.5 mg/l > 24 mm | > 1 mg/l < 21 mm |
| S. pneumoniae | ≤ 0.5 mg/l > 22 mm | > 0.5 mg/l < 22 mm |
| Streptococcus Groups A, B, C, G | ≤ 0.5 mg/l > 18 mm | > 1 mg/l < 15 mm |
| H. influenzae | ≤ 0.5 mg/l > 25 mm | ≤ 0.5 mg/l > 25 mm |
| M. catarrhalis | ≤ 0.5 mg/l > 23 mm | > 0.5 mg/l < 23 mm |
| Enterobacteriaceae | ≤ 0.5 mg/l > 20 mm | > 1 mg/l < 17 mm |
| Non-species related breakpoints* | ≤ 0.5 mg/l | > 1 mg/l |
| * Non-species related breakpoints have been determined mainly on the basis of pharmacokinetic/pharmacodynamic data and are independent of MIC distributions of specific species. They are for use only for species that have not been given a species-specific breakpoint and are not for use with species where interpretative criteria remain to be determined. | ||
Microbiological Susceptibility
The prevalence of acquired resistance may vary geographically and with time for selected species and local information of resistance is desirable, particularly when treating severe infections. As necessary, expert advice should be sought where the local prevalence of resistance is such that utility of the agent in at least some types of infections is questionable.
| Commonly susceptible species |
| Aerobic Gram-positive micro-organisms Staphylococcus aureus*+ Streptococcus agalactiae (Group B) Streptococcus milleri group* (S. anginosus, S. constellatus and S. intermedius) Streptococcus pneumoniae* Streptococcus pyogenes* (Group A) Streptococcus viridans group (S. viridans, S. mutans, S. mitis, S. sanguinis, S. salivarius, S. thermophilus) |
| Aerobic Gram-negative micro-organisms Acinetobacter baumanii Haemophilus influenzae* Legionella pneumophila Moraxella (Branhamella) catarrhalis* |
| Anaerobic micro-organisms Prevotella spp. |
| “Other†micro-organisms Chlamydophila (Chlamydia) pneumoniae* Coxiella burnetii Mycoplasma pneumoniae* |
| Species for which acquired resistance may be a problem |
| Aerobic Gram-positive micro-organisms Enterococcus faecalis* Enterococcus faecium* |
| Aerobic Gram-negative micro-organisms Enterobacter cloacae* Escherichia coli*# Klebsiella oxytoca Klebsiella pneumoniae*# Proteus mirabilis* |
| Anaerobic micro-organisms Bacteroides fragilis* |
| Inherently resistant organisms |
| Aerobic Gram-negative micro-organisms Pseudomonas aeruginosa |
| *Activity has been satisfactorily demonstrated in clinical studies. +Methicillin resistant S. aureus have a high probability of resistance to fluoroquinolones. Moxifloxacin resistance rate of > 50% have been reported for methicillin resistant S. aureus. #ESBL-producing strains are commonly also resistant to fluoroquinolones. |
Absorption and Bioavailability
After a single 400 mg intravenous 1 hour infusion peak plasma concentrations of approximately 4.1 mg/l were observed at the end of the infusion corresponding to a mean increase of approximately 26% relative to those seen after oral administration (3.1 mg/l). The AUC value of approximately 39 mg-h/l after i.v. administration is only slightly higher than that observed after oral administration (35 mg-h/l) in accordance with the absolute bioavailability of approximately 91%.
In patients, there is no need for age or gender related dose adjustment on intravenous moxifloxacin.
Pharmacokinetics are linear in the range of 50 - 1200 mg single oral dose, up to 600 mg single intravenous dose and up to 600 mg once daily dosing over 10 days.
Distribution
Moxifloxacin is distributed to extravascular spaces rapidly. The steady-state volume of distribution (Vss) is approximately 2 l/kg. In vitro and ex vivo experiments showed a protein binding of approximately 40 - 42% independent of the concentration of the drug. Moxifloxacin is mainly bound to serum albumin.
Maximum concentrations of 5.4 mg/kg and 20.7 mg/l (geometric mean) were reached in bronchial mucosa and epithelial lining fluid, respectively, 2.2 h after an oral dose. The corresponding peak concentration in alveolar macrophages amounted to 56.7 mg/kg. In skin blister fluid concentrations of 1.75 mg/l were observed 10 h after intravenous administration. In the interstitial fluid unbound concentration time profiles similar to those in plasma were found with unbound peak concentrations of 1.0 mg/l (geometric mean) reached approximately 1.8 h after an intravenous dose.
Biotransformation
Moxifloxacin undergoes Phase II biotransformation and is excreted via renal (approximately 40%) and biliary/faecal (approximately 60%) pathways as unchanged drug as well as in the form of a sulpho-compound (M1) and a glucuronide (M2). M1 and M2 are the only metabolites relevant in humans, both are microbiologically inactive.
In clinical Phase I and in vitro studies no metabolic pharmacokinetic interactions with other drugs undergoing Phase I biotransformation involving cytochrome P450 enzymes were observed. There is no indication of oxidative metabolism.
Elimination
Moxifloxacin is eliminated from plasma with a mean terminal half life of approximately 12 hours. The mean apparent total body clearance following a 400 mg dose ranges from 179 to 246 ml/min. Following a 400 mg intravenous infusion recovery of unchanged drug from urine was approximately 22% and from faeces approximately 26%. Recovery of the dose (unchanged drug and metabolites) totalled to approximately 98% after intravenous administration of the drug. Renal clearance amounted to about 24 - 53 ml/min suggesting partial tubular reabsorption of the drug from the kidneys. Concomitant administration of moxifloxacin with ranitidine or probenecid did not alter renal clearance of the parent drug.
Renal impairment
The pharmacokinetic properties of moxifloxacin are not significantly different in patients with renal impairment (including creatinine clearance > 20 ml/min/1.73 m2). As renal function decreases, concentrations of the M2 metabolite (glucuronide) increase by up to a factor of 2.5 (with a creatinine clearance of < 30 ml/min/1.73 m2).
Hepatic impairment
On the basis of the pharmacokinetic studies carried out so far in patients with liver failure (Child Pugh A, B), it is not possible to determine whether there are any differences compared with healthy volunteers. Impaired liver function was associated with higher exposure to M1 in plasma, whereas exposure to parent drug was comparable to exposure in healthy volunteers. There is insufficient experience in the clinical use of moxifloxacin in patients with impaired liver function.
Plasma concentrations of moxifloxacin were measured in healthy adult male and female subjects who received bilateral topical ocular doses of Megaxin® solution 3 times a day. The mean steady-state Cmax (2.7 ng/mL) and estimated daily exposure AUC (45 ng•hr/mL) values were 1,600 and 1,000 times lower than the mean Cmax and AUC reported after therapeutic 400 mg doses of moxifloxacin. The plasma half-life of moxifloxacin was estimated to be 13 hours.
In conventional repeated dose studies moxifloxacin revealed haematological and hepatic toxicity in rodents and non-rodents. Toxic effects on the CNS were observed in monkeys. These effects occurred after the administration of high doses of moxifloxacin or after prolonged treatment.
In dogs, high oral doses (> 60 mg/kg) leading to plasma concentrations > 20 mg/l caused changes in the electroretinogram and in isolated cases an atrophy of the retina.
After intravenous administration findings indicative of systemic toxicity were most pronounced when moxifloxacin was given by bolus injection (45 mg/kg) but they were not observed when moxifloxacin (40 mg/kg) was given as slow infusion over 50 minutes.
After intra-arterial injection inflammatory changes involving the peri-arterial soft tissue were observed suggesting that intra-arterial administration of moxifloxacin should be avoided.
Moxifloxacinwas genotoxic in in vitro tests using bacteria or mammalian cells. In in vivo tests, no evidence of genotoxicity was found despite the fact that very high moxifloxacin doses were used. Moxifloxacin was non-carcinogenic in an initiation-promotion study in rats.
In vitro, moxifloxacin revealed cardiac electrophysiological properties that can cause prolongation of the QT interval, even though at high concentrations.
After intravenous administration of moxifloxacin to dogs (30 mg/kg infused over 15, 30 or 60 minutes) the degree of QT prolongation was clearly depending on the infusion rate, i.e. the shorter the infusion time the more pronounced the prolongation of the QT interval. No prolongation of the QT interval was seen when a dose of 30 mg/kg was infused over 60 minutes.
Reproductive studies performed in rats, rabbits and monkeys indicate that placental transfer of moxifloxacin occurs. Studies in rats (p.o. and i.v.) and monkeys (p.o.) did not show evidence of teratogenicity or impairment of fertility following administration of moxifloxacin. A slightly increased incidence of vertebral and rib malformations was observed in foetuses of rabbits but only at a dose (20 mg/kg i.v.) which was associated with severe maternal toxicity. There was an increase in the incidence of abortions in monkeys and rabbits at human therapeutic plasma concentrations.
Quinolones, including moxifloxacin, are known to cause lesions in the cartilage of the major diarthrodial joints in immature animals.
This product is for single use only. Any unused solution should be discarded.
The following co-infusions were found to be compatible with moxifloxacin 400 mg solution for infusion:
Water for injections, Sodium chloride 0.9%, Sodium chloride 1 molar, Glucose 5%/10%/40%, Xylitol 20%, Ringer's solution, Compound Sodium Lactate Solution (Hartmann's Solution, Ringer-Lactate Solution).
Moxifloxacin solution for infusion should not be co-infused with other drugs.
Do not use if there are any visible particulate matter or if the solution is cloudy.
At cool storage temperatures precipitation may occur, which will re-dissolve at room temperature. It is therefore recommended not to store the infusion solution below 15°C.
However, we will provide data for each active ingredient
