Back to the Future: Intravenous Fosfomycin is Safe and Effective for the Treatment of Complicated Infections in Children

BACKGROUND

Despite its broad spectrum and excellent safety profile, fosfomycin is still rarely used in pediatrics, with very limited experience from clinicians.

METHODS

We retrospectively reviewed the medical records of all children admitted to Bambino Gesù Children's Hospital, IRCCS, Rome, Italy, and treated with fosfomycin for any serious infection. Children with immunodeficiency and oncologic diseases were excluded. Of each, we reported and analyzed demographic and clinical data.

RESULTS

The clinical charts of 20 patients were reviewed and analyzed. The mean age was 10.2 years. Most children were males (85%). Most patients treated had an osteo-articular infection (65%). In our sample, 7 patients (35%) had an underlying comorbidity. The causative agent was isolated in 14 cases (70%). All patients were treated with a combination of 2-3 antibiotics, including fosfomycin. The average duration of antibiotic treatment was 18 days. After treatment, 8 patients (40%) experienced a mild adverse reaction, possibly correlated with the administration of fosfomycin. All patients were discharged in good clinical condition.

CONCLUSIONS

The present study reports on a sample of pediatric patients with complicated infections where administration of fosfomycin led to eradication of the disease with little or no side effects. Role of the underlying condition and concomitant medication in causing the reaction could not be ruled out. These data suggest that fosfomycin is an effective and safe antibiotic in the pediatric population, particularly for deep-seated infections sustained by multi-drug resistant pathogens.

Parenteral Fosfomycin in Gastrointestinal Surgery: A Systematic Review

BACKGROUND

To investigate if perioperative parenteral administration of fosfomycin given before or during gastrointestinal surgery could protect against postoperative infectious complications and characterise the administration of fosfomycin and its harms.

METHODS

This systematic review included original studies on gastrointestinal surgery where parental administration of fosfomycin was given before or during surgery to≥5 patients. We searched three databases on March 24 2023 and registered the protocol before data extraction (CRD42020201268). Risk of bias was assessed with Cochrane Handbook risk of bias assessment tool or the Newcastle-Ottawa Scale. A narrative description was undertaken. For infectious complications, results from emergency and elective surgery were presented separately.

RESULTS

We included 15 unique studies, reporting on 1,029 patients that received fosfomycin before or during gastrointestinal surgery. Almost half of the studies were conducted in the 1980s to early 1990s, and typically a dose of 4 g fosfomycin was given before surgery co-administered with metronidazole and often repeated postoperatively. The risk of bias across studies was moderate to high. The rates of infectious complications were low after fosfomycin; the surgical site infection rate was 0-1% in emergency surgery and 0-10% in elective surgery. If reported, harms were few and mild and typically related to the gastrointestinal system.

CONCLUSION

There were few postoperative infectious complications after perioperative parenteral administration of one or more doses of 4 g fosfomycin supplemented with metronidazole in various gastrointestinal procedures. Fosfomycin was associated with few and mild harms.

Fosfomycin-induced agranulocytosis: a case report and review of the literature

BACKGROUND

The intravenous form of fosfomycin, a bactericide antibiotic used to treat multiresistant bacterial infections is little prescribed. The most common reported adverse effects are hypokaliemia and hypernatremia. We describe a case of agranulocytosis, a rarely described side effect that may be fatal.

CASE PRESENTATION

A 45 year-old woman was admitted to the intensive care unit for post-surgical meningitis following meningioma resection. Meropenem and vancomycin were first introduced. A DRESS-syndrom with meropenem was suspected. Neutropenia was diagnosed three days after the introduction of parenteral fosfomycin and agranulocytosis four days later. Eosinophilia was also observed. A bone marrow aspiration was performed showing a disappearance of the neutrophil granulocyte line and a significant eosinophilia. Meropenem was discontinued. Fosfomycin was maintained and filgrastim was added. As filgrastim had no effect, the relationship with fosfomycin was suspected, so it was then withheld. An increase of the neutrophil count was observed. Because of the complexity of the case, the unfavorable course of the illness and the urgent need for revision surgery, a rechallenge with fosfomycin was done followed by a decrease of the neutrophil count.

CONCLUSION

This is the third paper reporting agranulocytosis induced by fosfomycin, and the first detailed description of a case. Based on chronological and semiological criteria and bibliographic data, the event was qualified as probable with the Naranjo adverse drug probability scale. Literature data is scarce. The summary of product characteristics mentions that only a few cases of transient neutropenia and agranulocytosis have been reported. An analysis of the FDA Adverse Event Reporting System Database highlighted a higher than expected frequency of agranulocytosis in patients treated with fosfomycin. Parenteral fosfomycin is often used in patients receiving other medications, so that it is rarely the only suspect. In our case, the results of the bone marrow aspiration, the sudden drop of the neutrophil count with concomitant eosinophilia and the absence of improvement despite the dose decrease, point towards an immuno-allergic mechanism. However, the overlap between the suspected DRESS induced by meropenem and the agranulocytosis do not allow to conclude with certainty on the causality. Awareness should be raised about this side effect.

Efficacy and safety of intravenous fosfomycin for the treatment of carbapenem-resistant Klebsiella pneumoniae

The aim of the study was to evaluate clinical and microbiological efficacy and safety of intravenous fosfomycin for the treatment of carbapenem-resistant K. pneumoniae infections. All adult inpatients receiving 48 h of intravenous fosfomycin, alone or combined with other antibiotics were included in the study. Overall favorable clinical response rate was 75.3% among 94 patients. Clinical response rates were 92.3%, 72.2% and 56.0% for urinary tract infections, bacteremia and pneumonia, respectively. Microbiological eradication was achieved in 55 of 86 patients. 30-day mortality was 33.0%. Adverse events were generally mild. Common adverse events were hypokalemia (37.2%) and hypernatremia (22.3%). Intravenous fosfomycin is an effective antibiotic option with a good safety profile for the treatment of carbapenem-resistant K. pneumoniae infections. The most favorable clinical and microbiological responses are obtained in urinary tract infections. The efficacy of the drug in more severe infections, such as pneumonia and bacteremia, is comparable to the literature.

Effectiveness of fosfomycin trometamol as oral step-down therapy for bacteraemic urinary tract infections due to MDR Escherichia coli: a post hoc analysis of the FOREST randomized trial

BACKGROUND

Fosfomycin is a potentially attractive option as step-down therapy for bacteraemic urinary tract infections (BUTI), but available data are scarce. Our objective was to compare the effectiveness and safety of fosfomycin trometamol and other oral drugs as step-down therapy in patients with BUTI due to MDR Escherichia coli (MDR-Ec).

METHODS

Participants in the FOREST trial (comparing IV fosfomycin with ceftriaxone or meropenem for BUTI caused by MDR-Ec in 22 Spanish hospitals from June 2014 to December 2018) who were stepped-down to oral fosfomycin (3 g q48h) or other drugs were included. The primary endpoint was clinical and microbiological cure (CMC) 5-7 days after finalization of treatment. A multivariate analysis was performed using logistic regression to estimate the association of oral step-down with fosfomycin with CMC adjusted for confounders.

RESULTS

Overall, 61 patients switched to oral fosfomycin trometamol and 47 to other drugs (cefuroxime axetil, 28; amoxicillin/clavulanic acid and trimethoprim/sulfamethoxazole, 7 each; ciprofloxacin, 5) were included. CMC was reached by 48/61 patients (78.7%) treated with fosfomycin trometamol and 38/47 (80.9%) with other drugs (difference, -2.2; 95% CI: -17.5 to 13.1; P = 0.38). Subgroup analyses provided similar results. Relapses occurred in 9/61 (15.0%) and 2/47 (4.3%) of patients, respectively (P = 0.03). The adjusted OR for CMC was 1.11 (95% CI: 0.42-3.29, P = 0.75). No relevant differences in adverse events were seen.

CONCLUSIONS

Fosfomycin trometamol might be a reasonable option as step-down therapy in patients with BUTI due to MDR-Ec but the higher rate of relapses would need further assessment.

[The efficiency of combined regimens for the treatment of urinary tract infections in women using the herbal drug Canephron N]

INTRODUCTION

Currently, empiric antibiotic therapy is considered the standard for acute cystitis. However, additional treatment may be required to alleviate the patient's condition and shorten the time to subjective recovery.

AIM

To evaluate the efficiency of the combined administration of fosfomycin trometamol and herbal drug Canephron N in comparison with a single oral dose of fosfomycin trometamol in women with uncomplicated bacterial cystitis.

MATERIALS AND METHODS

A randomized, comparative, open-label study was carried put between January 2018 and June 2019. The study included 112 women with symptoms of acute uncomplicated cystitis, who were randomized between two groups in a 1:1 ratio. In the main group, patients received a single oral dose of fosfomycin in combination with Canephron N (2 tablets t.i.d. for 2 weeks), while in the control group patients received only a single dose of fosfomycin (3 g). Symptoms were assessed using the Russian version of the Acute Cystitis Symptom Score (ACSS), completed daily for a week. Also, all patients underwent urine analysis on the 1st, 3rd, 5th and 7th days of therapy. The mean time to complete recovery based on the ACSS questionnaire and the time to resolution of pyuria were compared using the Mann-Whitney U test. Comparison of the proportion of patients with complete cure, according to the questionnaire, or with the elimination of pyuria was carried out using the chi-square test.

RESULTS

The final analysis included 46 patients who received fosfomycin in combination with Canephron and 47 patients who received fosfomycin as monotherapy. In the group of combination therapy, patient-reported complete recovery (assessed by the ACSS questionnaire) was seen on average after 1 day, while in patients treated with monotherapy, the median time to subjective recovery was 3 days (p=0.00012). A significant difference between the groups in the proportion of patients with complete resolution of symptoms of acute cystitis was observed on days 1, 2, and 3 (p<0.05). The therapy was well tolerated in both groups. The most frequent adverse events were dyspepsia (8.7% in the combination group compared to 6.4% in the control group) and headache (in 4.3% and 6.4% of patients, respectively).

CONCLUSION

the combined use of fosfomycin trometamol and the herbal drug Canephron N allows to reduce the duration of symptoms in patients with acute cystitis, thereby accelerating return to their usual lifestyle patterns.

Efficacy and safety of intravenous fosfomycin for the treatment of difficult-to-treat Gram-negative bacterial infections

We reviewed the efficacy and safety of intravenous (IV) fosfomycin for the treatment of infections caused by Gram-negative bacteria (GNB) with difficult-to-treat resistance (DTR). Data were retrospectively retrieved for all hospitalized patients who received IV fosfomycin for ≥48 h for the treatment of a DTR GNB between September 27, 2017 and January 31, 2020. A total of 30 patients were included, of which 63.3% were males, and the median age was 63.5 years (IQR 46-73). The median Charlson Comorbidity Score was 6 (IQR 3.8-9). The urinary tract (56.7%) was the most frequent site of infection, and the most frequent target organisms were Klebsiella pneumoniae (56.7%), and Escherichia coli (23.3%). The majority (76.%) received IV fosfomycin in combination with other antibacterial agents. Clinical improvement was observed in 22 (73.3%), eradication of baseline pathogens in 20 (66.7%), 30-day all-cause mortality in 7 (23.3%), and documented emergent resistance to fosfomycin in 5 (16.7%) patients. Treatment-related adverse events were infrequent and generally mild or moderate in severity. In conclusion, IV fosfomycin is a potentially efficacious and safe treatment option for the treatment of DTR GNB infections. Randomized trials are urgently required to confirm the utility of IV fosfomycin as monotherapy and in combination with other agents.

[Rationale for the choice of an antibiotic for urinary tract infections with an emphasis on the environmental safety of therapy]

Difficulties in prescribing antibiotics for lower urinary tract infections (UTI) are associated with a fact that such patients can be treated not only by urologists, but also by general practitioners, internists, pediatricians, and gynecologists. Therefore, it is important to adapt the practical recommendations for the treatment of cystitis for different medical disciplines. When creating clinical guidelines, experts take into account the different factors in choosing antibiotic therapy. First of all, pharmacokinetics is of importance and drugs with renal excretion should be preferred. Secondly, the natural activity of the antibiotic against the pathogens, which cause cystitis, has to be considered. In uncomplicated infections, E. coli predominates, while in complicated and recurrent infections E. coli and other enterobacteria are commonly isolated, as well as Enterococci. In addition, local resistance pattern is reviewed. In the Russian Federation E. coli has minimal resistance to nitrofurans and fosfomycin. Lastly, antibiotics can negatively affect the gastrointestinal and urinary tract microbiota and contribute to the increase of antibiotic resistance and the selection of antibiotic-resistant strains, therefore the environmental safety of therapy should be considered. The effect of antibiotics on the resident flora of the gastrointestinal tract, urinary tract and vagina is called collateral effect, or concomitant (parallel) damage, and it may exceed the therapeutic effect of some antibiotics. Cephalosporins and fluoroquinolones can cause ecologically unfavorable effects with the risk of selection of resistant strains; therefore, these drugs are currently considered as second-line agents for UTI. When choosing an antibiotic, preference should be given to drugs with the narrow spectrum and minimal collateral damage, i.e., the principle of "minimum sufficiency" is of importance. Nitrofurans and fosfomycin trometamol are the optimal drugs in terms of efficiency and environmental safety in UTI. WHO experts consider nitrofurans as the most environmentally safe antibiotics with a minimally sufficient spectrum of activity. The environmental safety of antimicrobial therapy is an important component of preventing antibiotic resistance at the global and local levels.

[Recurrent lower urinary tract infection in women: treatment and prevention]

INTRODUCTION

Antibiotics represent the main drugs for the treatment and prevention of recurrent lower urinary tract infections (UTIs). At the same time, there is no consensus regarding the duration of therapy and the interval between courses.

MATERIAL AND METHODS

A total of 50 women aged 18 to 65 years (mean age 44.6+/-13.2 years) with recurrent lower UTIs in the acute stage were treated. All patients were prescribed fosfomycin trometamol (Fosfomycin Esparma, Esparma GmbH, Germany) at a dose of 3 g once every 10 days for 3 months. The changes of clinical and laboratory parameters were evaluated on the 3rd day after the first administration of fosfomycin, and then after 1, 3 and 6 months from the start of treatment.

RESULTS

A decrease in the severity of clinical manifestations of cystitis was seen on the next day after first administration of fosfomycin. By the 3rd day, the ACSS score decreased from the initial 9.2+/-2.1 to 1.4+/-1.0 (p<0.001), while the average urinary frequency changed from 12.3+/-2.3 to 7.5+/-1.4 (p<0.05). After 3 months of therapy, the clinical results virtually did not differ from results on the 3rd day. The therapy was well tolerated; adverse events were noted in 10 patients, but they didnt result in discontinuation of the drug. During follow-up for 3 months after the completion of therapy, 47 (94%) women didnt have recurrence of lower UTI.

CONCLUSION

the results of the study suggest a high efficiency and good tolerability of fosfomycin when it is prescribed according to specific scheme for the treatment and prevention of recurrent lower UTIs in women.

A comparison of different antibiotic regimens for the treatment of infective endocarditis

BACKGROUND

Infective endocarditis is a microbial infection of the endocardial surface of the heart. Antibiotics are the cornerstone of treatment, but due to the differences in presentation, populations affected, and the wide variety of micro-organisms that can be responsible, their use is not standardised. This is an update of a review previously published in 2016.

OBJECTIVES

To assess the existing evidence about the clinical benefits and harms of different antibiotics regimens used to treat people with infective endocarditis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase Classic and Embase, LILACS, CINAHL, and the Conference Proceedings Citation Index - Science on 6 January 2020. We also searched three trials registers and handsearched the reference lists of included papers. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing the effects of antibiotic regimens for treating definitive infective endocarditis diagnosed according to modified Duke's criteria. We considered all-cause mortality, cure rates, and adverse events as the primary outcomes. We excluded people with possible infective endocarditis and pregnant women.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, 'Risk of bias' assessment, and data extraction in duplicate. We constructed 'Summary of findings' tables and used GRADE methodology to assess the quality of the evidence. We described the included studies narratively.

MAIN RESULTS

Six small RCTs involving 1143 allocated/632 analysed participants met the inclusion criteria of this first update. The included trials had a high risk of bias. Three trials were sponsored by drug companies. Due to heterogeneity in outcome definitions and different antibiotics used data could not be pooled. The included trials compared miscellaneous antibiotic schedules having uncertain effects for all of the prespecified outcomes in this review. Evidence was either low or very low quality due to high risk of bias and very low number of events and small sample size. The results for all-cause mortality were as follows: one trial compared quinolone (levofloxacin) plus standard treatment (antistaphylococcal penicillin (cloxacillin or dicloxacillin), aminoglycoside (tobramycin or netilmicin), and rifampicin) versus standard treatment alone and reported 8/31 (26%) with levofloxacin plus standard treatment versus 9/39 (23%) with standard treatment alone; risk ratio (RR) 1.12, 95% confidence interval (CI) 0.49 to 2.56. One trial compared fosfomycin plus imipenem 3/4 (75%) versus vancomycin 0/4 (0%) (RR 7.00, 95% CI 0.47 to 103.27), and one trial compared partial oral treatment 7/201 (3.5%) versus conventional intravenous treatment 13/199 (6.53%) (RR 0.53, 95% CI 0.22 to 1.31). The results for rates of cure with or without surgery were as follows: one trial compared daptomycin versus low-dose gentamicin plus an antistaphylococcal penicillin (nafcillin, oxacillin, or flucloxacillin) or vancomycin and reported 9/28 (32.1%) with daptomycin versus 9/25 (36%) with low-dose gentamicin plus antistaphylococcal penicillin or vancomycin; RR 0.89, 95% CI 0.42 to 1.89. One trial compared glycopeptide (vancomycin or teicoplanin) plus gentamicin with cloxacillin plus gentamicin (13/23 (56%) versus 11/11 (100%); RR 0.59, 95% CI 0.40 to 0.85). One trial compared ceftriaxone plus gentamicin versus ceftriaxone alone (15/34 (44%) versus 21/33 (64%); RR 0.69, 95% CI 0.44 to 1.10), and one trial compared fosfomycin plus imipenem versus vancomycin (1/4 (25%) versus 2/4 (50%); RR 0.50, 95% CI 0.07 to 3.55). The included trials reported adverse events, the need for cardiac surgical interventions, and rates of uncontrolled infection, congestive heart failure, relapse of endocarditis, and septic emboli, and found no conclusive differences between groups (very low-quality evidence). No trials assessed quality of life.

AUTHORS' CONCLUSIONS

This first update confirms the findings of the original version of the review. Limited and low to very low-quality evidence suggests that the comparative effects of different antibiotic regimens in terms of cure rates or other relevant clinical outcomes are uncertain. The conclusions of this updated Cochrane Review were based on few RCTs with a high risk of bias. Accordingly, current evidence does not support or reject any regimen of antibiotic therapy for the treatment of infective endocarditis.

Effect of 5-Day Nitrofurantoin vs Single-Dose Fosfomycin on Clinical Resolution of Uncomplicated Lower Urinary Tract Infection in Women: A Randomized Clinical Trial

IMPORTANCE

The use of nitrofurantoin and fosfomycin has increased since guidelines began recommending them as first-line therapy for lower urinary tract infection (UTI).

OBJECTIVE

To compare the clinical and microbiologic efficacy of nitrofurantoin and fosfomycin in women with uncomplicated cystitis.

DESIGN, SETTING, AND PARTICIPANTS

Multinational, open-label, analyst-blinded, randomized clinical trial including 513 nonpregnant women aged 18 years and older with symptoms of lower UTI (dysuria, urgency, frequency, or suprapubic tenderness), a positive urine dipstick result (with detection of nitrites or leukocyte esterase), and no known colonization or previous infection with uropathogens resistant to the study antibiotics. Recruitment took place from October 2013 through April 2017 at hospital units and outpatient clinics in Geneva, Switzerland; Lodz, Poland; and Petah-Tiqva, Israel.

INTERVENTIONS

Participants were randomized in a 1:1 ratio to oral nitrofurantoin, 100 mg 3 times a day for 5 days (n = 255), or a single 3-g dose of oral fosfomycin (n = 258). They returned 14 and 28 days after therapy completion for clinical evaluation and urine culture collection.

MAIN OUTCOMES AND MEASURES

The primary outcome was clinical response in the 28 days following therapy completion, defined as clinical resolution (complete resolution of symptoms and signs of UTI without prior failure), failure (need for additional or change in antibiotic treatment due to UTI or discontinuation due to lack of efficacy), or indeterminate (persistence of symptoms without objective evidence of infection). Secondary outcomes included bacteriologic response and incidence of adverse events.

RESULTS

Among 513 patients who were randomized (median age, 44 years [interquartile range, 31-64]), 475 (93%) completed the trial and 377 (73%) had a confirmed positive baseline culture. Clinical resolution through day 28 was achieved in 171 of 244 patients (70%) receiving nitrofurantoin vs 139 of 241 patients (58%) receiving fosfomycin (difference, 12% [95% CI, 4%-21%]; P = .004). Microbiologic resolution occurred in 129 of 175 (74%) vs 103 of 163 (63%), respectively (difference, 11% [95% CI, 1%-20%]; P = .04). Adverse events were few and primarily gastrointestinal; the most common were nausea and diarrhea (7/248 [3%] and 3/248 [1%] in the nitrofurantoin group vs 5/247 [2%] and 5/247 [1%] in the fosfomycin group, respectively).

CONCLUSIONS AND RELEVANCE

Among women with uncomplicated UTI, 5-day nitrofurantoin, compared with single-dose fosfomycin, resulted in a significantly greater likelihood of clinical and microbiologic resolution at 28 days after therapy completion.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01966653.

Intravenous fosfomycin for pulmonary exacerbation of cystic fibrosis: Real life experience of a large adult CF centre

BACKGROUND

The increased prevalence of multi-drug resistant strains of P.aeruginosa and allergic reactions among adult patients with cystic fibrosis (CF) limits the number of antibiotics available to treat pulmonary exacerbations. Fosfomycin, a unique broad spectrum bactericidal antibiotic, might offer an alternative therapeutic option in such cases.

AIM

To describe the clinical efficacy, safety and tolerability of intravenous fosfomycin in combination with a second anti-pseudomonal antibiotic to treat pulmonary exacerbations in adult patients with CF.

METHOD

A retrospective analysis of data captured prospectively, over a 2-years period, on the Unit electronic medical records for patients who received IV fosfomycin was performed. Baseline characteristics in the 12 months prior treatment, lung function, CRP, renal and liver function and electrolytes at start and end of treatment were retrieved.

RESULTS

54 patients received 128 courses of IV fosfomycin in combination with a second antibiotic, resulting in improved FEV1 (0.94 L vs 1.24 L, p < 0.01) and reduced CRP (65 mg/L vs 19.3 mg/L, p < 0.01). Renal function pre- and post-treatment remained stable. 4% (n = 5) of courses were complicated with AKI at mid treatment, which resolved at the end of the course. Electrolyte supplementation was required in 18% of cases for potassium and magnesium and 7% for phosphate. Nausea was the most common side effect (48%), but was well controlled with anti-emetics.

CONCLUSION

Antibiotic regimens including fosfomycin appear to be clinically effective and safe. Fosfomycin should, therefore, be considered as an add-on therapy in patients who failed to respond to initial treatment and with multiple drug allergies.

Fosfomycin for UTIs

Fosfomycin trometamol is a broad spectrum antibiotic recently marketed in the UK for the treatment of acute uncomplicated lower urinary tract infections (UTIs) in adults^1,2 and in adult and adolescent females.³ It is also indicated for prophylaxis in diagnostic and surgical transurethral procedures.^1-3 Fosfomycin was discovered in 1969 and the reference drug was first marketed as Monuril in France in 1986.^3,4 Although Monuril had UK marketing authorisation, it was never distributed in the UK. However, national guidance included the option of using unlicensed imported fosfomycin.^3,5,6 Branded and generic versions of fosfomycin are now available in the UK,^1-3,7 and here we review the evidence for their use in the treatment of UTIs.

[Fosfomycin--its significance for treatment of diseases due to multidrug-resistant bacteria]

Fosfomycin is a bactericidal phosphonic acid derivative, which engages by inhibiting pyruvyltransferase at an early stage in the peptidoglycan synthesis. It shows a broad spectrum of activity that includes many multidrug-resistant gram-negative and gram-positive bacteria. Fosfomycin is active against most strains of Pseudomonas aeruginosa and several multidrug-resistant Enterobacteriaceae, e.g., Escherichia coli strains expressing extended spectrum beta-lactamases (ESBL) and Klebsiella pneumoniae strains with decreased susceptibilities to carbapenems. Most methicillin-resistant Staphylococcus aureus (MRSA) strains as well as enterococci with and without vancomycin resistance are also sensitive to fosfomycin. During the last decade, a variety of studies showed that fosfomycin is not only suitable for treating uncomplicated urinary tract diseases, but also for the treatment of many other diseases caused by bacterial pathogens with and without multidrug resistance. However, large controlled studies demonstrating the efficacy of the drug to treat diseases caused by multidrug-resistant bacteria are still missing. Considering the low number of antibacterial agents with good activity against multidrug-resistant bacteria, fosfomycin should be evaluated as an important antibiotic for the treatment of several severe illnesses due to these pathogens. However, because some multidrug-resistant bacteria are also resistant to fosfomycin, this agent should only be applied if the pathogen is sensitive to this drug. In addition, because rapid development of resistance cannot be excluded if fosfomycin will be applied alone, this drug should only be given in combination with other effective drugs for the treatment of serious systemic diseases due to multidrug-resistant bacterial pathogens.

Recurrent uncomplicated cystitis in women: allowing patients to self-initiate antibiotic therapy

Acute uncomplicated cystitis is a lower urinary tract infection occurring in the absence of anatomic or functional abnormalities of the urinary tract or any other complicating factors.The organism responsible is often an enterobacterium, especially Escherichia coli. What is the role of antibiotic therapy for non-pregnant women with recurrent acute uncomplicated cystitis? We reviewed the available evidence using the standard Prescrire methodology. A single oral dose of fosfomycin trometamol is the antibiotic of choice for treating an episode of acute uncomplicated cystitis. Alternative antibiotics are certain fluoroquinolones or co-trimoxazole (a fixed-dose combination of sulfamethoxazole and trimethoprim). For recurrent acute uncomplicated cystitis, cranberry juice has modest efficacy in reducing the frequency of episodes. A number of non-drug measures are typically proposed, although their effects are unproven: drinking sufficient fluids and urinating regularly; urinating after sexual intercourse; and avoiding spermicides. The strategy that results in the lowest antibiotic exposure is a short course of antibiotics for each episode of urinary tract infection, initiated as soon as clinical symptoms appear. Long-term antibiotic therapy is sometimes offered. According to one systematic review, women taking long-term prophylactic antibiotic therapy had about 6 times fewer clinical recurrences than with placebo. According to one randomised trial, 3 g of fosfomycin trometamol taken as a single dose every ten days reduced the frequency of recurrence, resulting in 0.14 episodes of infection per year on average versus about 3 episodes with placebo (p < 0.001). The amount of antibiotic used when fosfomycin trometamol is taken every 10 days for 6 months is equivalent to treatment of 18 acute episodes of cystitis. When cystitis appears to be associated with sexual intercourse, two small randomised trials suggest that routine postcoital antibiotic treatment is more effective than placebo and as effective as long-term antibiotic therapy. Adverse effects, some of which can be serious, depend on the antibiotic used. The development of resistance among enterobacteria is one argument for limiting the use of antibiotics, in order to preserve their efficacy in serious infections. In practice, the strategy that uses the fewest antibiotics is to treat each episode as soon as the first clinical symptoms appear. Cases in which the frequency of recurrence warrants regular antibiotic prophylaxis are rare. The optimal antibiotic regimen in these cases has not been determined, either in clinical trials or by consensus.

[Revival of selected well-tried antibiotics. Special features of the antiinfective agents penicillin G, fosfomycin, aztreonam and colistin]

Although a worldwide increasing incidence of bacterial infections with panresistant pathogens may need innovative antiinfective agents, no breakthrough developments can be expected in the near future. As a consequence, well-tried antibiotics like aztreonam, fosfomycin and colistin, are experiencing a clinical revival, particularly if they are used in an improved manner. Even penicillin G with its narrow spectrum of antimicrobial activity remains an important considerable agent of first choice in special indications compared to broad spectrum antiinfectives.

[Clinical aspects of antimicrobial therapy used in patients with urogenital infections]

AIM

To study the clinical aspects of using the furasidine potassium in combination with basic magnesium carbonate (furamag) and phosphomycin trometamol (monural) as antimicrobial agents most frequently used in outpatient practice during combination therapy for acute and chronic urinary tract (UT) diseases.

SUBJECTS AND METHODS

To study the specific features of therapy for UT infections, 60 patients were randomized to 2 groups: 1) 30 patients received a course therapy with furasidine potassium (furamag) in a dose of 50 mg t.i.d. for 7 days (a study group) and 2) 30 had phosphomycin trometamol (monural) in a single dose of 3 g for pulse therapy (a comparison group). The clinical efficacy of the drugs, symptom disappearance rates, bacterial changes, and laboratory and instrumental findings were assessed. The patient's opinion was mainly used to evaluate outpatient pharmacoeconomic efficiency. Patient compliance with the given therapy was estimated by taking into account the specific features of prehospital care.

RESULTS

During therapy, both groups showed positive clinical changes. In the study group, the symptoms of dysuria resolved 0.5 days more quickly and a complete clinical remission was achieved 0.8 days more promptly; the latter within the first 72 hours was achieved by 7.5% more of the patients; the symptoms of bacteriuria resolved 0.6 days more rapidly. With the similar average price of the packs of furasidine potassium (furamag) 50 mg (30 capsules) and phosphomycin trometamol (monural) 1 g (a sachet) being 350 and 370 rubles, the average costs of required treatment were 482 and 546 rubles, respectively. No case of adverse reactions was recorded during the study.

CONCLUSION

Patients with infectious and inflammatory diseases of UT should be given furasidine potassium in the standard dose of 50 mg t.i.d for 7 days.

Clinical effects of 2 days of treatment by fosfomycin calcium for acute uncomplicated cystitis in women

Fosfomycin calcium is a fosfomycin antimicrobial agent with a characteristic structure. After oral administration, the drug is absorbed and excreted via the kidneys in the unchanged form, without being metabolized in the body. It is, therefore, indicated for the treatment of urinary tract diseases, including cystitis and pyelonephritis. In the present study, the clinical usefulness of fosfomycin calcium (FOSMICIN® TABLETS 500) administered orally at the dosage of 1 g (two tablets) three times daily for 2 days was examined in female patients, who were at least 20 years of age, with acute uncomplicated cystitis of bacterial origin. Of the 48 patients enrolled between February 2008 and August 2008, 39 were evaluable for efficacy and safety. Overall evaluation of the cure revealed that microbiological eradication rate (microbiological outcome) and clinical efficacy rate (clinical outcome) at 5-9 days after drug administration (visit 2) were 94.9%. Determination of the microbiological and clinical outcomes for the evaluation of recurrence at 4-6 weeks after drug administration (visit 3) were 75.8 and 85.7%, respectively. Of the 48 patients, 40 (83.3%) returned to the clinic at visit 3. The causative bacterial species for cystitis was Escherichia coli in 31 (79.5%) of the 39 patients evaluable for efficacy and safety. Adverse drug reactions observed during the administration and follow-up periods included mild diarrhea and loose stools in 1 patient each, neither requiring any specific treatment. Evaluation of cure at visit 2 in patients in whom the causative bacterial species for the infection was E. coli revealed a microbiological outcome of 93.5%, and clinical outcome was 96.8%. Furthermore, evaluation for recurrence at visit 3 revealed a microbiological outcome of 74.1% and clinical outcome of 82.1%. When the patients were divided by age into an under 60 years of age group and an over 60 years of age group, the microbiological and clinical outcomes determined for evaluation of cure at visit 2 were 96.4 and 92.9%, respectively, and the corresponding rates determined for the evaluation of recurrence at visit 3 were 87.0 and 96.0%, respectively, in the under 60 years of age group. In the over 60 years of age group, the corresponding microbiological outcome and clinical outcome rates evaluated for cure were 90.9 and 100%, respectively, and those evaluated for recurrence were 50.0 and 60.0%, respectively. These results indicate the usefulness of fosfomycin calcium administered at 1 g three times daily for 2 days for acute uncomplicated cystitis.

Fosmidomycin plus clindamycin for treatment of pediatric patients aged 1 to 14 years with Plasmodium falciparum malaria

Fosmidomycin plus clindamycin was shown to be efficacious in the treatment of uncomplicated Plasmodium falciparum malaria in a small cohort of pediatric patients aged 7 to 14 years, but more data, including data on younger children with less antiparasitic immunity, are needed to determine the potential value of this new antimalarial combination. We conducted a single-arm study to improve the precision of efficacy estimates for an oral 3-day fixed-ratio combination of fosmidomycin and clindamycin at 30 and 10 mg/kg of body weight, respectively, every 12 hours for the treatment of uncomplicated P. falciparum malaria in 51 pediatric outpatients aged 1 to 14 years. Fosmidomycin plus clindamycin was generally well tolerated, but relatively high rates of treatment-associated neutropenia (8/51 [16%]) and falls of hemoglobin concentrations of > or =2 g/dl (7/51 [14%]) are of concern. Asexual parasites and fever were cleared within median periods of 42 h and 38 h, respectively. All patients who could be evaluated were parasitologically and clinically cured by day 14 (49/49; 95% confidence interval [CI], 93 to 100%). The per-protocol, PCR-adjusted day 28 cure rate was 89% (42/47; 95% CI, 77 to 96%). Efficacy appeared to be significantly reduced in children aged 1 to 2 years, with a day 28 cure rate of only 62% for this small subgroup (5/8). The inadequate efficacy in children of <3 years highlights the need for continued systematic studies of the current dosing regimen, which should include randomized trial designs.

Short-course regimens of artesunate-fosmidomycin in treatment of uncomplicated Plasmodium falciparum malaria

Fosmidomycin is effective against malaria, but it needs to be given for > or =4 days when used alone. We conducted a study of 50 children with Plasmodium falciparum malaria to evaluate the safety and efficacy of consecutively shortened regimens of artesunate-fosmidomycin (1 to 2 mg/kg of body weight and 30 mg/kg of body weight, respectively; doses given every 12 hours). All dosing regimens were well tolerated. Artesunate-fosmidomycin acted rapidly, resulting in consolidated geometric mean parasite and fever clearance times of 24 h and 15 h, respectively. Treatment regimens of > or =2 days led to cure ratios of 100% by day 14 (39/39; 95% confidence interval [95% CI], 91% to 100%). Most importantly, the 3-day regimen achieved 100% cure on day 28 (10/10; 95% CI, 69% to 100%). Treatment with artesunate-fosmidomycin was associated with transient grade I or II neutropenia (absolute neutrophil counts of 750 to 1,200/microl and 400 to 749/microl, respectively) in six or two patients, respectively. Artesunate-fosmidomycin demonstrates the feasibility and potential value of short-course artemisinin-based combination chemotherapy with rapidly eliminated combination partners.

Prevention of recurrent lower urinary tract infections by long-term administration of fosfomycin trometamol. Double blind, randomized, parallel group, placebo controlled study

Three hundred and seventeen non pregnant females, suffering of recurrent lower urinary tract infections (UTIs; at least three episodes in the preceding 12 months) were enrolled in a double blind, randomized placebo (PL) controlled, parallel group clinical study, addressed to evaluate the efficacy and safety of fosfomycin trometamol (CAS 78964-85-9, FT, Monuril) in the prevention of infectious recurrences of lower urinary tract. One hundred and sixty six and 151 patients were allocated at random to FT or to PL treatment. The assigned treatment, i.e. one sachet containing FT equivalent to 3 g. of fosfomycin or PL, was taken by patients every 10 days during 6 months; thereafter they were followed up for another 6 consecutive months. Three hundred and two evaluable patients, completed the study as per protocol, 158 in the FT and 144 in the PL group, respectively. The analysis of the number of urinary tract infections/patient-year (primary end point) showed a result of 0.14 infections/patient-year in the FT group and of 2.97 infections/patient-year in the PL group. The difference was highly significant (p < 0.001). The time to first infection recurrence was significantly longer in the FT (38 days) than in the PL group (6 days); p < 0.01. The number of patients with at least one episode of recurrent infection and the number of episodes/patient during the treatment as well as during the follow-up period were statistically significantly lower in the FT group than in the PL group. Both treatments were well tolerated; only one adverse reaction possibly treatment related, i.e. an allergic skin reaction, was reported in both groups. Haematology and blood chemistry variables explored for safety at the end of the study did not show any significant difference between the two groups. The compliance with the treatment in the 302 evaluable patients was excellent. The results of this trial indicate that FT is higly effective in the prophylaxis of UTI recurrences; this beneficial effect is evident also in the 6 months of the follow-up.

Fosmidomycin-clindamycin for the treatment of Plasmodium falciparum malaria

It has been demonstrated that fosmidomycin has good tolerability and rapid onset of action, but late recrudescences preclude its use alone; in vitro, clindamycin has been shown to act synergistically with fosmidomycin against Plasmodium falciparum. We conducted a study in pediatric outpatients with P. falciparum malaria in Gabon to evaluate the efficacy and safety of an oral combination of fosmidomycin-clindamycin of 30 mg/kg and 10 mg/kg of body weight, respectively, every 12 h. Patients 7-14 years old were recruited in cohorts of 10. The first 10 patients were treated for 5 days. The duration of treatment was then incrementally shortened in intervals of 1 day if >85% of the patients in a cohort were cured by day 14. All dosing regimens were well tolerated, and no serious adverse events occurred. Asexual parasites and fever rapidly cleared in all patients. Cure ratios of 100% on day 14 were achieved with treatment durations of 5 (10/10 patients), 4 (10/10 patients), 3 (10/10 patients), and 2 days (10/10 patients); 1 day of treatment led to a cure ratio of 50% (5/10 patients). Fosmidomycin-clindamycin is safe and well tolerated, and short-course regimens achieved high efficacy in children with P. falciparum malaria. Fosmidomycin-clindamycin is a promising novel treatment option for malaria.

Fosmidomycin-clindamycin for Plasmodium falciparum Infections in African children

BACKGROUND

Fosmidomycin is a new antimalarial drug with a novel mechanism of action. Studies in Africa that have evaluated fosmidomycin as monotherapeutic agent demonstrated its excellent tolerance, but 3-times-daily treatment regimens of >or=4 days were required to achieve radical cure, prompting further research to identify and validate a suitable combination partner to enhance its efficacy.

METHODS

We conducted a randomized, controlled, open-label study to evaluate the efficacy and safety of fosmidomycin combined with clindamycin (n=12; 30 and 5 mg/kg body weight every 12 h for 5 days, respectively), compared with fosmidomycin alone (n=12; 30 mg/kg body weight every 12 h for 5 days) and clindamycin alone (n=12; 5 mg/kg body weight every 12 h for 5 days) for the clearance of asymptomatic Plasmodium falciparum infections in schoolchildren in Gabon aged 7-14 years.

RESULTS

Asexual parasites were rapidly cleared in children treated with fosmidomycin-clindamycin (median time, 18 h) and fosmidomycin alone (25 h) but slowly in children treated with clindamycin alone (71 h; P=.004). However, only treatment with fosmidomycin-clindamycin or clindamycin alone led to the radical elimination of asexual parasites as measured by day 14 and 28 cure rates of 100%. Asexual parasites reappeared by day 28 in 7 children who received fosmidomycin (day 14 cure rate, 92% [11/12; day 28 cure rate, 42% [5/12]). All regimens were well tolerated, and no serious adverse events occurred.

CONCLUSION

The combination of fosmidomycin and clindamycin is well tolerated and superior to either agent on its own with respect to the rapid and radical clearance of P. falciparum infections in African children.

Why fosfomycin trometamol as first line therapy for uncomplicated UTI?

Uncomplicated urinary tract infection (UTI) is one of the most common conditions requiring diagnostic and therapeutic intervention. The aetiology and the treatment of these infectious diseases have changed little during last years of the 'antibiotic era'. Escherichia coli is the most prevalent uropathogen (85->90%) and treatment is aimed at eradicating the infection using shorter regimes that typically may employ a 3-day course with once-a-day dosing of a selected drug or a single dose of a particular efficacious antibiotic. Antibiotic resistance to commonly used agents, such as trimethoprim and ampicillin, often now exceeds 30-50%, while fosfomycin trometamol, despite many years of usage, continues to be characterized by an extremely low incidence of E. coli resistant strains (about 1%) worldwide. Many factors may have contributed to preserve fosfomycin trometamol antibacterial activity including single dose usage limited to urinary infections, very high and sustained urinary concentrations that rapidly kill bacteria reducing the opportunity for mutant selection. In addition there is no animal feed that contains the drug, resistance is most commonly acquired by chromosomal mutations that do not spread easily and the biological cost of these genetic modifications is high. To these parameters fosfomycin trometamol adds excellent tolerability and safety. Although nowadays, microbial resistance limits available resources and some drugs can no longer be recommended as reliable agents, fosfomycin trometamol, because of its properties, remains a drug of choice for the eradication of uncomplicated UTI.

Fosfomycin therapy for multiresistant Pseudomonas aeruginosa in cystic fibrosis

BACKGROUND

Increasing resistance to standard antibiotics has been demonstrated in CF patients colonised by Pseudomonas aeruginosa. The antibiotic Fosfomycin has a unique mode of action against this organism, and may protect against aminoglycoside mediated renal and ototoxic effects. However, there is little published experience of this drug in IV form, and it is not licensed for use in the UK.

METHODS

In combination with other antibiotics, we used Fosfomycin to treat 30 pulmonary exacerbations in 15 adult CF patients colonised by P. aeruginosa, mainly multiresistant strains. All patients gave informed consent. We cultured sputum prior to treatment and measured spirometry, renal function, and symptoms before and after treatment, and recorded any side effects.

RESULTS

One patient developed nausea and Fosfomycin treatment was withdrawn. The remaining patients showed clinical resolution of their chest exacerbations (mean FEV1% predicted: pre 41.1 vs. post 49.4, P<0.001). Although there was a statistical increase in plasma urea (pre 3.9 mmol/l vs. post 4.3, P<0.03), this was still within the normal range. Plasma creatinine was unchanged.

CONCLUSIONS

This study shows that IV Fosfomycin is well tolerated by adult patients with CF and can be useful in the treatment of those colonised with multiresistant P. aeruginosa.

Fosmidomycin for malaria

Safe and effective antimalarial drugs with new methods of action are urgently needed. Fosmidomycin inhibits the synthesis of isoprenoid by Plasmodium falciparum, and suppresses the growth of multidrug-resistant strains in vitro. Our aim was to assess the efficacy and tolerability of fosmidomycin in adults with malaria in Gabon. We administered the drug for 5, 4, or 3 days (1.2 g every 8 h), in nine, eight, and ten evaluable patients, respectively. All treatment regimens were well tolerated. Cure rates by day 14 were 89% (eight of nine), 88% (seven of eight), and 60% (six of ten), for treatment durations of 5, 4, and 3 days, respectively. These data suggest that fosmidomycin is a safe and effective treatment for uncomplicated malaria if given for 4 days or more.

Empirical treatment of adult postsurgical nosocomial meningitis

BACKGROUND

The combination of cefotaxime and fosfomycin (CTX-FOS) has been proposed in France for the empirical treatment of postoperative nosocomial meningitis since the late 1980s. The purpose of this work was to evaluate this strategy today, as well as other possible treatments.

METHODS

Each patient undergoing a neurosurgical procedure was prospectively included in a database designed for the surveillance of surgical site infection (SSI). For each meningitis detected, we analysed the in vitro susceptibility of the causative micro-organisms to cefotaxime alone (CTX), cefotaxime-fosfomycin (CTX-FOS), vancomycin (VAN) and cefotaxime-vancomycin (CTX-VAN) combinations. The patient population was divided into two groups according to the presence or absence of CSF shunting material.

FINDINGS

116 patients had had a postoperative meningitis/ventriculitis during the last 36 months, among 6447 patients undergoing neurosurgery in our department (1.8%). Ten patients had aseptic meningitis (8.6%). Overall sensitivity to CTX was 69.8%, as compared to 77.3% with CTX-FOS combination (NS). This result was due to a large proportion of fosfomycin resistant cocci in our population. The CTX-VAN combination increased the overall in vitro susceptibility up to 91.5%, but the benefit of this combination was only significant in CSF shunting material patients. In these latter patients, VAN was as effective as CTX-FOS combination.

INTERPRETATION

CTX-FOS combination is no longer the best choice for empirical treatment of post neurosurgical meningitis. CTX alone can be safely used in patients without a CSF shunt; in those with either a ventriculostomy or a CSF shunt associated ventriculitis, a CTX-VAN combination could improve treatment efficacy, provided that high doses of vancomycin are used to ensure correct CSF diffusion.

Acute, recurrent fosfomycin-induced liver toxicity in an adult patient with cystic fibrosis

We report a very unusual adverse effect--fosfomycin-induced repeat liver toxicity--in a female adult with cystic fibrosis (CF).

Single-dose treatment of acute cystitis with fosfomycin tromethamine

OBJECTIVE

To review the clinical pharmacology of fosfomycin tromethamine, a new antimicrobial agent for the treatment of uncomplicated lower urinary tract infections (UTIs).

DATA SOURCE

Publications in English on fosfomycin, fosfomycin tromethamine, and fosfomycin trometamol (MEDLINE, 1970-1997), as well as unpublished studies submitted to the Food and Drug Administration (FDA), were reviewed.

STUDY SELECTION

Comparative, randomized, controlled studies were used to analyze the efficacy and safety of fosfomycin tromethamine.

DATA SYNTHESIS

Fosfomycin tromethamine is an oral antimicrobial indicated for the treatment of uncomplicated lower UTIs. This agent is active in the urine against common uropathogens that are associated with cystitis in women, including organisms resistant to other antibiotics. A single dose of fosfomycin tromethamine is well absorbed and produces therapeutic concentrations in the urine for 2-4 days. Comparative clinical trials suggest that a single dose of fosfomycin tromethamine 3.0 g is as clinically effective as 7- to 10-day treatment regimens of standard agents used to treat UTIs, such as nitrofurantoin, norfloxacin, and trimethoprim/sulfamethoxazole. Fosfomycin tromethamine is well tolerated and appears safe to use during pregnancy.

CONCLUSIONS

Fosfomycin tromethamine is the only antimicrobial to be approved by the FDA for single-dose therapy in women with acute cystitis. It is as effective and safe as multidose comparators and appears safe to use during pregnancy. The acquisition cost of this new drug will need to be weighed against the improved compliance and convenience associated with its use in the treatment of uncomplicated UTIs.

[A combined consecutive therapy with fosfomycin and sulbactam/cefoperazone for bacterial infections associated with hematological diseases]

A combination antibacterial therapy with fosfomycin (FOM) and sulbactam/cefoperazone (SBT/CPZ) was applied to 78 patients with severe infections associated with hematological diseases. In this protocol, FOM was followed by SBT/CPZ and each drug was administered for 1 hour intravenously and consecutively. Among 72 evaluable patients, 43 patients had acute leukemia, myeloblastic or lymphoblastic, 22 had malignant lymphoma, 3 had multiple myeloma, and 4 had other hematological diseases as underlying diseases. Bacterial infections diagnosed were sepsis in 21 patients, suspected sepsis in 47, and other infections in 4. The overall efficacy rate of this treatment was 72.2%, and those for individual infections were 66.7% for sepsis, 74.5% for suspected sepsis, and 75.0% for other infectious diseases. Among 22 bacteria separated from patients with sepsis, 78.6% (11/14 strains) were eradicated by this treatment. This protocol was also effective in 57.1% (8/14) of patients whose granulocyte count was less than 100/mm3 during the course of treatment as well as in 83.3% (15/18) of patients with granulocyte count over 500/mm3. There was no difference in effectiveness between those patients to whom G-CSF was administered and those to whom it was not (17/24, 70.8% vs 35/48, 72.9%). As an adverse reaction, a transient increase of GOT and/or GPT was observed in 2 patients (2.8%). The consecutive administration treatment of FOM and SBT/CPZ is thus an effective and safe regimen for the treatment of patients with hematological diseases complicated by severe infections.

Fosfomycin trometamol in a single dose versus seven days nitrofurantoin in the treatment of acute uncomplicated urinary tract infections in women

In general practice acute uncomplicated urinary tract infections in women are treated with different courses of antibiotics. In this study the efficacy and tolerability of a single dose of 3 g fosfomycin trometamol and the conventional treatment with nitrofurantoin 50 mg four times daily for seven days were compared. In a randomized, double-blind, double-dummy trial in 31 general practices in the Netherlands 231 patients with symptoms of acute dysuria, stranguria and/or urinary frequency received treatment. Evaluation was based on resolution of symptoms, dipslide results and side-effects at 4, 9 and 42 days after starting the treatment. The clinical cure rates and bacteriological cure rates were not significantly different between the treatment groups. Side-effects were reported at day 4 by 43% of the women receiving single-dose treatment, compared with 25% of the women in the seven-day treatment group, a significant difference. At day 9 the groups did not significantly differ in the number of patients with side-effects. Almost all side-effects were mild and gastro-intestinal complaints were reported most. Taking into account the convenience of taking a single dose we conclude that fosfomycin trometamol is a reasonable alternative to 7 days nitrofurantoin 50 mg four times a day in the treatment of women with symptoms of acute uncomplicated urinary tract infections in general practice.

Analysis of oral fosfomycin calcium (Fosmicin) side-effects after marketing

For about 6 years after the marketing of oral formulations of fosfomycin calcium (FOM-Ca) in December, 1980, we collected the data on 35,481 cases and analyzed it regarding safety. Primary side-effects consisted mainly in gastrointestinal disturbances, damage to skin and adnexa, liver and bile duct disorders. Specifically, diarrhea, nausea, abdominal pain, anorexia, eruption and increased serum transaminase were frequent. Serious and newly detected side-effects after marketing were pseudomembranous colitis and melena, one case each. As for the oral administration of FOM-Ca to 83 patients hypertensive to beta-lactams, gastrointestinal side-effects were seen but none of them developed hypersensitivity, an allergic reaction.

Side effects of repeated ototopical application of fosfomycin. An animal study

In view of the possible role of fosfomycin in the topical treatment of chronic suppurative otitis media, the effects of this drug on inner ear function were investigated. Fosfomycin (20% aqueous solution) was applied repeatedly to the round window membrane of both ears of pigmented guinea pigs. Hearing thresholds were determined by daily frequency-specific evoked response audiometry with stimulation frequencies ranging from 1 to 32 kHz. Both positive (neomycin) and negative (saline) controls were included. Results were analyzed statistically. No significant and progressive hearing loss was found with fosfomycin. At 32 kHz, however, the hearing levels at the end of the test period were significantly worse in the fosfomycin group than in the saline group.

Single-dose fosfomycin trometamol (Monuril) versus multiple-dose norfloxacin: results of a multicenter study in females with uncomplicated lower urinary tract infections

The results of an open, randomized study comparing the efficacy and safety of Fosfomycin trometamol (Monuril), 3-gram single dose, and Norfloxacin (Noroxine 400), 400 mg twice daily for 5 days, are reported. Clinical and bacteriological assessments were performed before and 3-4 (short-term) and 25-30 days (long-term) after treatment. Only female patients with uncomplicated lower urinary tract infection were eligible for inclusion in the study: 33 cases were given Fosfomycin trometamol and 30 cases Norfloxacin. In the overall etiology, Escherichia coli (74% of the strains found), Proteus mirabilis (6%) and Klebsiella pneumoniae (6%) are highly predominant. With regard to bacteriological efficacy, the percentages of eradication in the two groups were similar: after the short-term test, 93.9% (31 of 33 patients) in the Fosfomycin trometamol group and 86.6% (26 of 30) in the Norfloxacin group, and after the long-term tests, 73.3% (22 of 30) in the Fosfomycin trometamol group and 77.89% (21 of 27) in the Norfloxacin group. There are no statistically significant differences. The duration of the reported side effects was significantly lower in the Fosfomycin trometamol group. The simplified dosage regimen (single dose) and its favorable benefit/risk ratio justifies the use of Fosfomycin trometamol as a treatment for uncomplicated urinary tract infections in female patients.

An open study of the efficacy and safety of single dose fosfomycin trometamol in treatment of hospitalised patients with urinary tract infection (pilot study)

Single dose fosfomycin trometamol (3 g) was used to treat 20 hospitalised patients with UTI. Tolerance was good or excellent in 19/20 patients; a satisfactory bacteriological outcome was recorded in 11/17 of patients with sensitive organisms and a satisfactory clinical outcome was noted in 12/16 symptomatic individuals.

A general practitioner multicenter study: fosfomycin trometamol single dose versus pipemidic acid multiple dose

In order to evaluate the efficacy and safety of fosfomycin trometamol as single dose oral treatment for acute cystitis in women, an open, multicenter comparative study was carried out in general practices in France, 386 women, aged 16 to 75 years, with clinical symptoms of acute cystitis were enrolled in the study to receive either a single 3 g oral dose of fosfomycin trometamol or a five-day course of 400 mg pipemidic acid twice daily. The diagnosis of cystitis was based on clinical symptoms and significant bacteriuria (greater than or equal to 10(5) cfu/ml midstream urine). Follow-up examinations were carried out five to ten and 28 days after the end of treatment, 289 and 244 patients, respectively, were available for clinical and bacteriological evaluation at short-term (five to ten days) and medium-term (28 days) post-treatment follow-up. Both regimens were comparable for clinical and bacteriological efficacy with short-term eradication rates of 122/146 in the fosfomycin trometamol group and 130/143 in the pipemidic acid group. The results of medium-term follow-up were 113/122 and 114/122 for the eradication rates of the respective groups. Both drugs were well tolerated. Side effects were mild and of significantly shorter duration in the fosfomycin trometamol group.

Prophylactic chemotherapy with fosfomycin trometamol versus placebo during transurethral prostatic resection

A prospective randomized controlled double-blind study was performed on 61 patients undergoing transurethral resection of the prostate. The first group of 31 patients received 3 g fosfomycin trometamol p.o. each on the evening before and after the operation; the second group of 30 patients received a placebo. Urine samples were taken by catheter puncture 24 and 48 h postoperative. After removal of the catheter (day 5) the first midstream urine was collected for culture, and from that moment on all patients were treated with a nitrofurantoin derivative for two weeks. Although the same strict antiseptic measures were standard practice for both groups, the incidence of early postoperative urinary tract infections was significantly lower for the fosfomycin trometamol group (0/31 versus 6/30 in placebo recipients). None of the patients suffered from a major symptomatic or complicated infection. There were no side effects registered.

Prophylactic chemotherapy with fosfomycin trometamol during transurethral surgery and urological manoeuvres. Results of a multicentre study

The aim of the present open prospective study is to evaluate the efficacy and safety profile of fosfomycin trometamol in the chemoprophylaxis of urinary tract infections following transurethral diagnostic and/or therapeutic manoeuvres. 712 patients were enrolled in 72 urological surgical centres. All the enrolled patients received an initial dose of fosfomycin trometamol (Monuril sachet containing 3 g of active drug in powder) 3 h before and a second dose 24 h after the transurethral manoeuvres. Clinical and microbiological examinations were carried out before the intervention, and then on the second and seventh days after the manoeuvres. 94 patients with positive baseline tests were excluded from the microbiological follow-up for non-compliance with the main inclusion criteria. Out of 618 patients with sterile urine or with bacteriuria less than 10(5) ml on baseline screening, 20 (3.2%) developed UTI on the second day and 22 (3.6%) on the seventh day after treatment. Clinical follow-up is in agreement with these microbiological data. Overall, a total of 24 side effects were observed (3.3%), 16 of which were associated with Monuril treatment. The results of this open study agree with the preliminary observations in the controlled studies.