This information is intended for use by health professionals

1. Name of the medicinal product

Fomicyt 40 mg/ml powder for solution for infusion

2. Qualitative and quantitative composition

One ml of reconstituted solution contains 40 mg fosfomycin.

Each bottle with 2.69 g of powder contains 2.64 g disodium fosfomycin, corresponding to 2 g fosfomycin and 0.64 g sodium, for reconstitution in 50 ml of solvent.

Each bottle with 5.38 g of powder contains 5.28 g disodium fosfomycin, corresponding to 4 g fosfomycin and 1.28 g sodium, for reconstitution in 100 ml of solvent.

Each bottle with 10.76 g of powder contains 10.56 g disodium fosfomycin, corresponding to 8 g fosfomycin and 2.56 g sodium, for reconstitution in 200 ml of solvent.

For a full list of excipients, see section 6.1.

3. Pharmaceutical form

Powder for solution for infusion.

White to cream-coloured powder.

4. Clinical particulars
4.1 Therapeutic indications

Fosfomycin is indicated for the treatment of the following infections in adults and children including neonates (see section 5.1):

- Osteomyelitis

- Complicated urinary tract infections

- Nosocomial lower respiratory tract infections

- Bacterial meningitis

- Bacteraemia that occurs in association with, or is suspected to be associated with, any of the infections listed above

Fosfomycin should be used only when it is considered inappropriate to use antibacterial agents that are commonly recommended for the initial treatment of the infections listed above, or when these alternative antibacterial agents have failed to demonstrate efficacy.

For information regarding the combination with other antibiotics see section 4.4 and 4.5.

Consideration should be given to official guidance on the appropriate use of antibacterial agents.

4.2 Posology and method of administration

The daily dose of fosfomycin is determined based on the indication, severity and site of the infection, susceptibility of the pathogen(s) to fosfomycin and the renal function. In children, it is also determined by age and body weight.

Adults and adolescents ≥ 12 years of age (> 40 kg):

Fosfomycin is primarily excreted renally unchanged. The general dosage guidelines for adults with estimated creatinine clearance > 80 ml/min are as follows:

Indication

Daily dose

Osteomyelitis

12–24 g a in 2–3 divided doses

Complicated urinary tract infection

12–16 g in 2–3 divided doses

Nosocomial lower respiratory tract infection

12–24 g a in 2–3 divided doses

Bacterial meningitis

16–24 g a in 3–4 divided doses

Individual doses must not exceed 8 g.

a The high-dose regimen in 3 divided doses should be used in severe infections expected or known to be caused by less susceptible bacteria.

There are limited safety data in particular for doses in excess of 16 g/day. Special caution is advised when such doses are prescribed.

Dosage in renal insufficiency

The dose recommendations for patients with renal impairment are based on pharmacokinetic modelling and limited clinical data; safety and efficacy have not yet been evaluated in clinical trials.

It is unclear if dose reductions are necessary for patients with an estimated creatinine clearance between 40–80 ml/min. Great caution should be exercised in these cases, particularly if doses at the higher end of the recommended range are considered.

In patients with impaired renal function the dose of fosfomycin must be adjusted to the degree of renal impairment.

Dose titration should be based on creatinine clearance values. In adults, creatinine clearance may be calculated according to the following formula by Cockroft and Gault:

In order to calculate CLCR in women, the result of this formula is multiplied by 0.85.

Dosage table for patients with impaired renal function:

CLCR patient

CLCR patient/ CLCR normal

Daily dosage recommended a

40 ml/min

0.333

70% (in 2–3 divided doses)

30 ml/min

0.250

60% (in 2–3 divided doses)

20 ml/min

0.167

40% (in 2–3 divided doses)

10 ml/min

0.083

20% (in 1–2 divided doses)

a The dose is expressed as a proportion of the dose that would have been considered appropriate if the patient's renal function were normal

The first dose should be increased by 100% (loading dose), but must not exceed 8 g.

Patients undergoing renal replacement therapy

Patients undergoing chronic intermittent dialysis (every 48 hours) should receive 2 g of fosfomycin at the end of each dialysis session.

During continuous veno-venous hemofiltration (post-dilution CVVHF), fosfomycin is effectively eliminated. Patients undergoing post-dilution CVVHF will not require any dose adjustment (see section 5.2).

No clinical data exist for intravenous fosfomycin in patients undergoing pre-dilution CVVHF or other forms of renal replacement therapy.

Hepatic impairment

There are no data indicating that dose adjustment is necessary in patients with hepatic impairment.

Elderly patients

The recommended doses for adults should be used in elderly patients. Caution is advised when considering the use of doses at the higher end of the recommended range (see also recommendations on dosage for patients with impaired renal function).

Paediatric population

Dose recommendations are based on very limited data.

Neonates, infants and children < 12 years of age (< 40 kg)

The dosage of fosfomycin in children should be based on age and body weight (BW):

Age/weight

Daily dose

Premature neonates

(age a < 40 weeks)

100 mg/kg BW in 2 divided doses

Neonates

(age a 40–44 weeks)

200 mg/kg BW in 3 divided doses

Infants 1–12 months

(up to 10 kg BW)

200–300 b mg/kg BW in 3 divided doses

Infants and children aged 1–12 years

(10–40 kg BW)

200–400 b mg/kg BW in 3–4 divided doses

a Sum of gestational and postnatal age.

b The high-dose regimen may be considered for severe infections and or serious infections (such as meningitis), in particular when known or suspected to be caused by organisms with moderate susceptibility.

No dose recommendations can be made for children with renal impairment.

Method and duration of administration

Method of administration

Disodium fosfomycin is intended for intravenous administration. The duration of infusion should be at least 15 minutes for the 2 g pack size, at least 30 minutes for the 4 g pack size and at least 60 minutes for the 8 g pack size.

Use only clear solutions.

As damaging effects can result from inadvertent intra-arterial administration of products not specifically recommended for intra-arterial therapy, it is essential to ensure that fosfomycin is only administered into veins.

For preparation of the solution for infusion see section 6.6.

Duration of treatment

Treatment duration should take into account the type of infection, the severity of the infection as well as the patient's clinical response. Relevant therapeutic guidelines should be adhered to when deciding treatment duration.

4.3 Contraindications

- Hypersensitivity to the active substance, fosfomycin, or to any of the excipients listed in section 6.1.

4.4 Special warnings and precautions for use

Consideration should be given to co-administering intravenous fosfomycin with another antibacterial agent, taking into account the remaining susceptibilities of the pathogen(s) under treatment. As it is unknown whether the development of resistance to intravenous fosfomycin is higher when it is used as a monotherapy, co-administration with other antibacterials should also be considered in order to prevent the emergence of resistance.

1 g fosfomycin (equivalent to 1.32 g disodium fosfomycin) contains 14 mmol (320 mg) sodium. One bottle with 2 g of fosfomycin contains 28 mmol (640 mg) sodium, one bottle with 4 g fosfomycin contains 56 mmol (1280 mg) sodium and one bottle with 8 g of fosfomycin contains 111 mmol (2560 mg) sodium.

A high sodium load associated with the use of fosfomycin may result in decreased levels of potassium in serum or plasma. A low-sodium diet is recommended during treatment. The substitution of potassium may be necessary in some cases. Serum electrolyte levels and water balance must be monitored during therapy. Caution is advised when fosfomycin is used in patients with cardiac insufficiency, hypertension, hyperaldosteronism, hypernatraemia or pulmonary oedema.

Acute, potentially life-threatening hypersensitivity reactions (anaphylactic shock) may occur in very rare cases. At the first signs (including sweating, nausea, cyanosis), the infusion of fosfomycin must be immediately discontinued. The intravenous line should be left in place. Depending upon the clinical situation, appropriate emergency measures may need to be initiated.

Antibacterial agent-associated colitis and pseudo-membranous colitis have been reported with nearly all antibacterial agents including fosfomycin, and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhoea during or subsequent to the administration of fosfomycin. Discontinuation of therapy with fosfomycin and the administration of specific treatment for Clostridium difficile should be considered. Medicinal products that inhibit peristalsis should not be given.

In patients with severe renal insufficiency (creatinine clearance ≤ 40ml/min), the elimination of fosfomycin is substantially slowed. See section 4.2 for appropriate dosing of fosfomycin in renal insufficiency.

4.5 Interaction with other medicinal products and other forms of interaction

No drug-drug interaction studies have been performed with fosfomycin. To date, no clinically relevant pharmacological interactions between fosfomycin and other agents (drugs, stimulants or foodstuffs) have been reported.

Combination with other antibiotics

In-vitro tests have shown that the combination of fosfomycin with a β-lactam antibiotic such as penicillin, ampicillin, cefazolin or the class of carbapenems, usually shows an additive to synergistic effect. The same applies to the combination of fosfomycin with most anti-staphylococcal (linezolid, quinupristin/dalfopristin, moxifloxacin) agents in the treatment of staphylococcal infections. The combination of fosfomycin with aminoglycosides has predominantly indifferent to additive effects.

4.6 Fertility, pregnancy and lactation

Fertility

To date, in humans no reduction in fertility after therapy with fosfomycin has been reported. In male and female rats, reduced fertility was observed after the oral administration of fosfomycin at supra-therapeutic doses (see section 5.3.).

Pregnancy

For fosfomycin, no clinical data on pregnancies are available. Animal studies do not indicate direct or indirect harmful effects with respect to pregnancy, embryonal/foetal development, parturition or postnatal development (see section 5.3). Fosfomycin should therefore not be prescribed to pregnant women unless the benefit outweighs the risk.

Lactation

After the administration of fosfomycin, low quantities of fosfomycin were found in human milk. Fosfomycin should therefore not be administered during lactation, unless the benefit outweighs the risk.

4.7 Effects on ability to drive and use machines

Occasionally, even if the product is correctly administered, side effects may occur which impair the ability to drive and use machines (see also section 4.8).

4.8 Undesirable effects

Summary of the safety profile

The most commonly reported adverse reactions during treatment are gastrointestinal disturbances and injection site reactions. Other important adverse reactions include hypokalaemia and/or hypernatraemia.

Tabulated list of adverse reactions

Undesirable effects are listed by body system and frequency in accordance with the following classification:

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

Not known:

cannot be estimated from the available data

System Organ Class

Frequency Category

Adverse Drug Reactions

Blood and lymphatic system disorders

Rare

Aplastic anaemia, eosinophilia

Frequency not known

Agranulocytosis, granulocytopenia, leucopenia, pancytopenia, thrombocytopenia, neutropenia

Immune system disorders

Very rare

Anaphylactic shock (see section 4.4)

Metabolism and nutrition disorders

Uncommon

Decreased appetite, hypernatraemia and/or hypokalaemia (see section 4.4), oedema

Psychiatric disorders

Frequency not known

Confusion

Nervous system disorders

Uncommon

Dysgeusia, headache

Eye disorders

Very rare

Visual impairment

Ear and labyrinth disorders

Uncommon

Vertigo

Cardiac disorders

Frequency not known

Tachycardia

Respiratory, thoracic and mediastinal disorders

Uncommon

Dyspnoea

Frequency not known

Asthmatic attack

Gastrointestinal disorders

Common

Retching, stomach ache

Uncommon

Nausea, vomiting, diarrhoea

Frequency not known

Pseudomembranous colitis (see section 4.4)

Hepatobiliary disorders

Uncommon

Blood alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase increased (transient)

Very rare

Fatty liver (completely reversible after discontinuation of fosfomycin)

Frequency not known

Hepatitis, cholestatic hepatitis, icterus

Skin and subcutaneous tissue disorders

Uncommon

Rash

Frequency not known

Angioedema, facial oedema, pruritus, urticaria

General disorders and administration site conditions

Common

Injection site phlebitis

Uncommon

Fatigue

Description of selected adverse reactions

Hypokalaemia may result in diffuse symptoms such as weakness, tiredness or oedema and/or muscle twitching. Severe forms may cause hyporeflexia and cardiac arrhythmia. Hypernatraemia may be associated with hypertension and signs of fluid overload such as oedema (see section 4.4).

Paediatric population

Limited safety information is available from the paediatric population. Frequency, type and severity of adverse reactions may be expected to be similar to the adult population.

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

To date, no cases of accidental overdose with clinically relevant intolerances have been reported. If an overdose is believed to have taken place, the patient must be monitored (particularly for plasma/serum electrolyte levels) and treated symptomatically. Fosfomycin is effectively cleared from the body by haemodialysis with a mean elimination half-life of approximately 4 hours.

5. Pharmacological properties
5.1 Pharmacodynamic properties

Pharmacotherapeutic group: antibiotics for systemic use, other antibacterials

ATC-Code: J01XX01

Mode of action

Fosfomycin exerts a bactericidal effect on proliferating pathogens by preventing the enzymatic synthesis of the bacterial cell wall. Fosfomycin inhibits the first stage of intracellular bacterial cell wall synthesis by blocking peptidoglycan synthesis.

Fosfomycin is actively transported into the bacterial cell via two different transport systems (the sn-glycerol-3-phosphate and hexose-6 transport systems).

Pharmacokinetic (PK)/pharmacodynamic (PD) relationship

Limited data indicate that fosfomycin most likely acts in a time-dependent manner.

Resistance mechanism

Main mechanism of resistance is a chromosomal mutation causing an alteration of the bacterial fosfomycin transport systems. Further resistance mechanisms, which are plasmid- or transposon-borne, cause enzymatic inactivation of fosfomycin by binding the molecule to glutathione or by cleavage of the carbon-phosphorus-bond in the fosfomycin molecule, respectively.

Cross-resistance

The mode of action of fosfomycin differs from that of all other antibiotic classes. Fosfomycin was generally found to be active in-vitro against clinical isolates of methicillin-resistant staphylococci, vancomycin-resistant enterococci, penicillin- and erythromycin-resistant streptococci and multiresistant Pseudomonas.

Antimicrobial spectrum of fosfomycin (in vitro)

The data predict only the probability of micro-organism susceptibility to fosfomycin.

For intravenous fosfomycin, the susceptibility breakpoints established by the European Committee on Antimicrobial Susceptibility Testing are as follows (EUCAST breakpoint table version 5.0, 2015):

Species

susceptible

resistant

Enterobacteriaceae

≤ 32 mg/l

> 32 mg/l

Staphylococcus spp.

≤ 32 mg/l

> 32 mg/l

The prevalence of acquired resistance of individual species may vary geographically and over time. Local information about the resistance situation is therefore necessary, particularly in order to ensure appropriate treatment of severe infections.

In-vitro activity spectrum of fosfomycin and resistance

The following table is based on the breakpoint according to EUCAST and comprises organisms relevant for the approved indications:

Commonly susceptible species

Aerobic Gram-positive microorganisms

Staphylococcus aureus

Streptococcus pyogenes

Streptococcus pneumoniae

Aerobic Gram-negative microorganisms

Citrobacter spp.

Edwardsiella spp.

Enterobacter cancerogenus

Escherichia coli

Haemophilus influenzae

Klebsiella oxytoca

Neisseria spp.

Proteus mirabilis

Proteus penneri

Providencia rettgeri

Anaerobic microorganisms

Peptococcus spp.

Peptostreptococcus spp.

Species in which acquired resistance may be a problem

Gram-positive microorganisms

Enterococcus faecalis

Staphylococcus epidermidis

Gram-negative microorganisms

Enterobacter cloacae

Klebsiella pneumonia

Proteus inconstans

Pseudomonas aeruginosa

Serratia marcescens

Inherently resistant species

Gram-negative microorganisms

Morganella morganii

Anaerobic microorganisms

Bacteroides spp.

The physiologically important apathogenic anaerobic species, Lactobacillus and Bifidobacterium, are not susceptible to fosfomycin.

5.2 Pharmacokinetic properties

Pharmacokinetics

A single intravenous infusion of 4 g and 8 g of fosfomycin in young healthy males resulted in maximum serum concentrations (Cmax) of approx. 200 and 400 μg/ml, respectively. The serum half-life was approx. 2 hours. In elderly and/or critically ill male and female subjects, single intravenous doses of 8 g of fosfomycin resulted in mean Cmax and half-lives in plasma of approximately 350–380 µg/ml and 3.6–3.8 h, respectively.

Distribution

The apparent volume of distribution of fosfomycin is approx. 0.30 l/kg body weight. Fosfomycin is distributed well to tissues. High concentrations are reached in eyes, bones, wound secretions, musculature, cutis, subcutis, lungs and bile. In patients with inflamed meninges, cerebrospinal fluid concentrations reach approx. 20–50% of the corresponding serum levels. Fosfomycin passes the placental barrier. Low quantities were found in human milk (about 8 % of the serum concentrations). The plasma protein binding is negligible.

Metabolism

Fosfomycin is not metabolised by the liver and does not undergo enterohepatic circulation. No accumulation is therefore to be expected in patients with hepatic impairment.

Elimination

80–90% of the quantity of fosfomycin administered to healthy adults is eliminated renally within 10 hours after a single intravenous administration. Fosfomycin is not metabolised, i.e. the biologically active compound is eliminated. In patients with normal or mildly to moderately impaired renal function (creatinine clearance ≥ 40 ml/min), approximately 50–60% of the overall dose is excreted within the first 3-4 hours.

Linearity

Fosfomycin shows linear pharmacokinetic behaviour after intravenous infusion of therapeutically used doses.

Special populations

Very limited data are available in special populations.

Elderly

No dose adjustment is necessary based on age alone. However, renal function should be assessed and the dose should be reduced if there is evidence of renal impairment (see section 4.2).

Paediatric population

The pharmacokinetics of fosfomycin in children and adolescents aged 3–15 years as well as in term newborns with normal renal function are generally similar to those of healthy adult subjects. However, in renally healthy neonates and infants up to 12 months, the glomerular filtration rate is physiologically decreased compared to older children and adults. This is associated with a prolongation of the elimination half-life of fosfomycin in dependence on the stage of renal maturation.

Renal insufficiency

In patients with impaired renal function, the elimination half-life is increased proportionally to the degree of renal insufficiency. Patients with creatinine clearance values of 40 ml/min or less require dose adjustments (see also section 4.2. “Dosage in renal insufficiency” for further details).

In a study investigating 12 patients under CVVHF customary polyethylene sulfone haemofilters with a membrane surface of 1.2 m2 and a mean ultrafiltration rate of 25 ml/min were employed. In this clinical setting, the mean values of plasma clearance and elimination half-life in plasma were 100 ml/min, and 12h, respectively.

Hepatic insufficiency

There is no requirement for dosage adjustments in patients with hepatic insufficiency since the pharmacokinetics of fosfomycin remains unaffected in this patient group.

5.3 Preclinical safety data

Subacute and chronic toxicity

The toxicity of fosfomycin following repeated administration for up to 6 months was evaluated in rats, dogs, rabbits and monkeys. At high intra-peritoneal doses of fosfomycin (> 500 mg/kg /day), rats developed respiratory arrest, tetanic cramps, anaemia, a reduction of blood protein levels, increased serum cholesterol and reduced blood glucose. Furthermore, dogs and monkeys experienced diarrhoea due to antibiotic-related changes in the intestinal flora following intravenous administration of doses of higher than 250 mg/kg /day and 500 mg/kg /day, respectively. In the rabbit, no toxicity was observed following intravenous administration of 400 mg/kg /day for a period of 1 month.

Reproductive toxicity

Fertility

In male and female rats, following repeated administration (via a pharyngeal tube) of up to 1400 mg/kg /day reduced fertility was observed at the maximum dose tested.

Teratogenicity

Fosfomycin was administered to mice, rats and rabbits via pharyngeal tube at maximum doses of 2 x 120 mg/kg /day, 1400 mg/kg /day and 420 mg/kg /day, respectively or intravenously to mice and rabbits at 55.3 mg/kg /day, and up to 250 mg/kg /day, respectively. There was no evidence of embryotoxicity or teratogenicity.

Perinatal and postnatal toxicity

In rats, a maximum dose of 2800 mg/kg /day was administered via a pharyngeal tube. There was no evidence of foetal or peri- and postnatal toxicity.

Mutagenicity

In-vitro tests were performed to test the alkylating capacity and the mutagenic effect of fosfomycin. Fosfomycin showed no alkylating effect. In the Ames test, no mutagenic effect was seen in test strains of Salmonella typhimurium (TA 98, TA 100, TA 1535, TA 1537 and TA 1538, with and without addition of rat-liver homogenate) after exposure to fosfomycin at up to 1600 µg/ml.

6. Pharmaceutical particulars
6.1 List of excipients

Succinic acid.

6.2 Incompatibilities

Although no chemical/pharmaceutical incompatibilities have been found, Fomicyt solutions should not be mixed together with other parenteral preparations with the exception of those listed in section 6.6.

6.3 Shelf life

4 years.

Chemical and physical in-use stability of the reconstituted solution that has been produced under aseptic conditions has been demonstrated for 24 hours at 25 °C if protected from light.

From a microbiological point of view, the product should be used immediately. If not used immediately, in-use storage times and conditions prior to use are the responsibility of the user and would normally not be longer than 24 hours at 2 to 8 °C, unless reconstitution has taken place in controlled and validated aseptic conditions.

6.4 Special precautions for storage

This medicinal product does not require any special storage conditions.

For storage of the reconstituted solution see section 6.3.

6.5 Nature and contents of container

Clear type-II glass bottles with a rubber stopper (bromobutyl rubber) and pull-off cap containing 2 g (in 100 ml bottle), 4 g (in 100 ml bottle) or 8 g (in 250 ml bottle) of Fomicyt, respectively, in packs of 10 bottles each.

Not all pack sizes may be marketed.

6.6 Special precautions for disposal and other handling

For single use only.

Any unused product or waste material should be disposed of in accordance with local requirements.

Preparation of the solution for infusion

In order to prepare the solution for infusion:

Fomicyt 2 g should be dissolved in 50 ml of Water for Injections, Glucose Infusion 50 mg/ml (5 %) or Glucose Infusion 100 mg/ml (10 %).

Fomicyt 4 g should be dissolved in 100 ml of Water for Injections, Glucose Infusion 50 mg/ml (5 %) or Glucose Infusion 100 mg/ml (10 %).

Fomicyt 8 g should be dissolved in 200 ml of Water for Injections, Glucose Infusion 50 mg/ml (5 %) or Glucose Infusion 100 mg/ml (10 %).

A slight degree of warming occurs when the powder is dissolved.

The reconstituted solution is clear and colourless to slightly yellowish.

Displacement value

The displacement values for the reconstituted solutions are 1 ml for the 2 g pack size, 2 ml for the 4 g pack size and 4 ml for the 8 g pack size.

These volumes are equivalent to an increase of volume of 2 %. This has to be considered when preparing the final solution in case of not using the entire content of the bottle.

7. Marketing authorisation holder

INFECTOPHARM Arzneimittel und Consilium GmbH

Von-Humboldt-Str. 1

64646 Heppenheim

Germany

Distributor

Nordic Pharma UK Ltd

Abbey House

1650 Arlington Business Park

Theale

Berkshire

RG7 4SA

8. Marketing authorisation number(s)

PL 15011/0017

9. Date of first authorisation/renewal of the authorisation

19/06/2015

10. Date of revision of the text

11/06/2017