Ciprofloxacin. An updated review of its pharmacology, therapeutic efficacy and tolerability

Pharmacokinetics and Pharmacodynamics of a Novel Extended-Release Ciprofloxacin in Healthy Volunteers

Two open-label, randomized, 2-way crossover studies (1 single-dose and 1 steady-state) were conducted in healthy volunteers to compare the pharmacokinetics and pharmacodynamics of a novel extended-release ciprofloxacin (ciprofloxacin ER; 500 mg once daily) and immediate-release ciprofloxacin (ciprofloxacin IR; 250 mg twice daily). For both studies, mean ciprofloxacin maximum concentration (Cmax) values after once-daily ciprofloxacin ER were significantly greater than those after the first daily dose of ciprofloxacin IR (P < .0001) but were lower than those after the second daily dose of ciprofloxacin IR (P < .05). The relative bioavailability of ciprofloxacin ER compared to ciprofloxacin IR was 93.8% in the single-dose study and 97.7% in the steady-state study. Mean urinary ciprofloxacin concentrations and excretion rates after either treatment were substantially greater than the minimum inhibitory concentrations (MICs) for susceptible uropathogens in both studies. The area under the concentration-time curve (AUC)/MIC, Cmax/MIC, amount excreted (Ae)/MIC, and Ae24/MIC ratios with ciprofloxacin ER were similar to or slightly greater than with ciprofloxacin IR for all susceptible organisms.

Synthesis and biological activities of some novel aminomethyl derivatives of 4-substituted-5-(2-thienyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiones

A novel series of compounds were synthesized by cyclic condensation reaction of substituted isothiocyanate (2a-c) with 2-thiophenecarboxylic acid hydrazide (1) in the presence of ethyl alcohol, to obtain intermediate thiosemicarbazides (3a-c), which were further treated with sodium hydroxide in the presence of ethanol to obtain triazole derivatives (4a-c). The latter were refluxed with substituted secondary amines and formaldehyde for 6-10 h to afford Mannich bases (5a-k). The synthesized compounds were characterized on the basis of their spectral (IR, (13)C and (1)H NMR) data and evaluated for biological activities. Some of the compounds were found to exhibit significant antimicrobial and antioxidant activity.

Randomized controlled trial comparing ciprofloxacin and cefepime in febrile neutropenic patients with hematological malignancies

BACKGROUND

Ciprofloxacin (CPFX) is a potential alternative in patients with febrile neutropenia (FN) because of its activity against Gram-negative organisms. We conducted a non-inferiority, open-label, randomized controlled trial comparing intravenous CPFX and cefepime (CFPM) for FN patients with hematological malignancies.

METHODS

Patients aged from 15 to 79 years with an absolute neutrophil count of <0.500 × 10(9/)l were eligible, and were randomized to receive 300 mg of CPFX or 2g of CFPM every 12h. Initial treatment efficacy, overall response, and early toxicity were evaluated.

RESULTS

Fifty-one episodes were included in this trial, and 49 episodes (CPFX vs. CFPM: 24 vs. 25) were evaluated. Treatment efficacy at day 7 was significantly higher in the CFPM group (successful clinical response: nine with CPFX and 19 with CFPM; p=0.007). The response was better in high-risk patients with neutrophil counts of ≤ 0.100 × 10(9/)l (p=0.003). The overall response during the study period was similar between the CPFX and CFPM groups (p=0.64). Adverse events were minimal, and all patients could continue the treatment.

CONCLUSIONS

We could not prove the non-inferiority of CPFX in comparison with CFPM for the initial treatment of FN. CFPM remains the standard treatment of choice for FN.

Effect of total and partial nephrectomy on the elimination of ciprofloxacin in humans

BACKGROUND

Renal cell carcinoma (RCC) is the most common form of kidney cancer. Surgery is a standard procedure to resect the tumor during total (TN) or partial (nephron-sparing) nephrectomy (PN). Ciprofloxacin is most often administered at the usual intravenous dose of 100-400 mg/12 h. The application of such low doses of ciprofloxacin as 200 mg/24 h carries the risk of achieving subtherapeutic concentrations even in patients with limited renal function. The aim of the study was a comparison of concentrations and pharmacokinetics for ciprofloxacin at steady-state in patients after total and partial nephrectomy and evaluation of the effectiveness of the iv dose 200 mg/24 h against the theoretical value of MIC, 0.5 μg/ml.

METHODS

The research was carried out on two groups of patients after nephrectomy: total (group 1, n = 21; mean [SD], age, 62.9 [14.4] years; weight, 76.0 [14.6] kg; creatinine clearance, CL(CR), 90.7 [22.2] ml/min) and partial (group 2, n = 15; 61.7 [9.3] years; 87.8 [16.4] kg; CL(CR), 107.8 [36.4] ml/min). The patients were treated with ciprofloxacin in the dose of 200 mg/24 h (iv). Plasma concentrations of ciprofloxacin at steady state were measured with validated HPLC method with UV detection.

RESULTS

The mean values of plasma concentrations of ciprofloxacin at steady state in group 1 and 2 were: C(ss)(max), 2.012 and 1.345; C(ss)(min), 0.437 and 0.244 μg/ml, respectively. The main pharmacokinetic parameters for ciprofloxacin in group 1 and 2 were as follows: AUC((0-last)), 30.9 [17.9] and 19.5 [8.7] μg h/ml; AUMC((0-last)), 177.91 [11.1] and 91.9 [66.5] μg h(2)/ml; t(1/2β), 13.9 [7.7] and 9.8 [3.3] h; MRT, 16.5 [12.1] and 9.77 [5.4] h; V(d), 115.0 [67.2] and 142.2 [78.7] l; CL, 6.2 [3.3] and 10.8 [5.7] l/h, respectively. With the assumed MIC = 0.5 μg/ml, the values of C(ss)(max)/MIC < 10 and AUC/MIC < 125 were obtained in all the patients.

CONCLUSION

In our patients we observed significant differences in some pharmacokinetic parameters of ciprofloxacin after two types of nephrectomy.

Pharmacokinetics and pharmacodynamics of ciprofloxacin in critically ill patients after the first intravenous administration of 400 mg

PURPOSE

To investigate the pharmacokinetics and pharmacodynamics of ciprofloxacin in critically ill patients after the first intravenous administration of 400 mg.

MATERIAL/METHODS

Plasma concentrations were measured in 20 critically ill patients (mean [SD]; age, 55.5 [16.5] years; weight, 80.3 [16.9] kg; and creatinine clearance, 110.0 [71.5] mL/min). Four blood samples were drawn at the following time points 0, 0.5, 6 , 8 hours after infusion. Ciprofloxacin concentrations were determined by high-performance liquid chromatography.

RESULTS

In the cases where ciprofloxacin was applied in targeted antibiotic therapy the minimum inhibitory concentrations (MIC) were ≤0.5 mg/l. The maximum and minimum plasma concentrations of ciprofloxacin were 1.74 (0.58-7.90) and 0.45 (0.16-2.96) mg/l, respectively. The main pharmacokinetic parameters for ciprofloxacin in the analyzed patients were as follows: k(el), 0.21 h-1; t(1/2kel), 3.37 h; AUC(0-inf), 10.10 mg×h/l; AUMC(0-last), 15.36 mg×h(2)/l; MRT, 1.71 h; V(d), 214.8 l; Cl, 39.70 l/h. Considering the maximum value of MIC (0.5 mg/l) only 30% and 25% of analyzed patients had desired values of the PK/PD indexes AUIC>125 and C(max) /MIC>10, respectively.

CONCLUSIONS

The target plasma concentrations after the first dose of ciprofloxacin were reached only in a few critically ill patients. Considerable inter-subject variability for PK/PD parameters in ICU patients requires systematic monitoring.

N-cyclohexyl-2-[5-(4-pyridyl)-4-(p-tolyl)-4H-1,2,4-triazol-3-ylsulfanyl]-acetamide dihydrate: synthesis, experimental, theoretical characterization and biological activities

The triazol compound N-cyclohexyl-2-[5-(4-pyridyl)-4-(p-tolyl)-4H-1,2,4-triazol-3-ylsulfanyl]-acetamide dihydrate has been synthesized and characterized by (1)H NMR, (13)C NMR, IR, and X-ray single-crystal determination. The molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) (1)H and (13)C NMR chemical shift values of III in the ground state have been calculated using the density functional method (B3LYP) with the 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure, and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values. The energetic behavior of III in solvent media was examined using the B3LYP method with the 6-31G(d) basis set by applying the Onsager and the polarizable continuum model (PCM). The predicted nonlinear optical properties of III are greater than ones of urea. In addition, DFT calculations of molecular electrostatic potentials, frontier molecular orbitals and thermodynamic properties of III were carried out at the B3LYP/6-31G(d) level of theory. The title compound was screened for antibacterial, antifungal and antioxidant activities.

Shelf-life extension program (SLEP) as a significant contributor to Strategic National Stockpile Maintenance: the Israeli experience with ciprofloxacin

In the past decade, the 2001 anthrax incident in the U.S. and the 2003 SARS epidemic have highlighted the biological threat to civilian populations. The risk posed by the natural or manmade spread of biological agents among the population dictates a need for better national preparedness. One key component of this preparation is the establishment of a Strategic National Stockpile (SNS) of pharmaceuticals that would provide appropriate medical countermeasures in case of an outbreak. However, to reduce the expense of such a stockpile and to make it worthwhile, there is also a need for a shelf-life extension program (SLEP) through which pharmaceuticals could be extended beyond manufacturer-ascribed shelf life, as long as they meet regulation standards. In this article, we review the Israeli experience with the national ciprofloxacin stockpile procurement and shelf-life extension program.

Design, synthesis of some new (2-aminothiazol-4-yl)methylester derivatives as possible antimicrobial and antitubercular agents

A series of (2-aminothiazol-4-yl)methylester (5a-t) derivatives were synthesized in good yields and characterized by (1)H NMR, (13)C NMR, mass spectral and elemental analyses. The crystal structure of 5a was evidenced by X-ray diffraction study. The compounds were evaluated for their preliminary in vitro antibacterial, antifungal activity and were screened for antitubercular activity against Mycobacterium tuberculosis H37Rv strain. The synthesized compounds displayed interesting antimicrobial activity.

Biodegradation of ciprofloxacin in water and soil and its effects on the microbial communities

While antibiotics are frequently found in the environment, their biodegradability and ecotoxicological effects are not well understood. Ciprofloxacin inhibits active and growing microorganisms and therefore can represent an important risk for the environment, especially for soil microbial ecology and microbial ecosystem services. We investigated the biodegradation of (14)C-ciprofloxacin in water and soil following OECD tests (301B, 307) to compare its fate in both systems. Ciprofloxacin is recalcitrant to biodegradation and transformation in the aqueous system. However, some mineralisation was observed in soil. The lower bioavailability of ciprofloxacin seems to reduce the compound's toxicity against microorganisms and allows its biodegradation. Moreover, ciprofloxacin strongly inhibits the microbial activities in both systems. Higher inhibition was observed in water than in soil and although its antimicrobial potency is reduced by sorption and aging in soil, ciprofloxacin remains biologically active over time. Therefore sorption does not completely eliminate the effects of this compound.

Paediatric use of second-line anti-tuberculosis agents: a review

Childhood multidrug-resistant tuberculosis (MDR-TB) is an emerging global epidemic. With the imminent roll-out of rapid molecular diagnostic tests, more children are likely to be identified and require treatment. As MDR-TB is resistant to the most effective first-line drugs, clinicians will have to rely on second-line medications which are less effective and often associated with more pronounced adverse effects than first-line therapy. Despite the fact that most of these agents were discovered many years ago, robust information is lacking regarding their pharmacokinetic and pharmacodynamic properties, adverse effects and drug interactions, especially in children. Children differ from adults in the way that drugs are administered, the manner in which they are metabolised and in the adverse effects experienced. The interaction of these drugs with human immunodeficiency virus infection and antiretroviral therapy is also poorly documented. This article reviews the available second-line drugs currently used in the treatment of MDR-TB in children and discusses medication properties and adverse effects while potential interactions with antiretroviral therapy are explored.

New quinolin-4-yl-1,2,3-triazoles carrying amides, sulphonamides and amidopiperazines as potential antitubercular agents

Three new series of quinoline-4-yl-1,2,3-triazoles carrying amides, sulphonamides and amidopiperazines were synthesized through multi-step reactions. The required intermediate, [1-(6-methoxy-2-methylquinolin-4-yl)-1H-1,2,3-triazol-4-yl]methanol (2) was prepared by treating 4-azido-6-methoxy-2-methylquinoline (1) with propargyl alcohol. Three different series of compounds were synthesized from this intermediate. All the newly synthesized compounds were characterized by spectral and elemental analyses. The structure of 2 was confirmed by X-ray crystallographic study. Further, the title compounds were evaluated for their in vitro anti-bacterial activity against five different bacterial strains and antimycobacterial activity against Mycobacterium tuberculosis H37Rv, Mycobacterium smegmatis (ATCC 19420) and Mycobacterium fortuitum (ATCC 19542). Title compounds, 6a, 6d, 6i, 6j, 7e, 10a and 10i were found to be active against Mycobacterium tuberculosis H37Rv strain and could be lead molecules of interest.

Pharmacokinetic interactions between ciprofloxacin and itraconazole in healthy male volunteers

OBJECTIVE

To investigate the pharmacokinetic interaction between ciprofloxacin and itraconazole in healthy male volunteers.

METHODS

Ten healthy male volunteers were assigned into a 2-sequence, 3-period pharmacokinetic interaction study. In phase 1, all subjects were randomly assigned to receive 500 mg of ciprofloxacin alone and 200 mg of itraconazole alone twice daily for 7 days with a 14 day wash-out period in a crossover design. Phase 2 was performed 14 days after finishing phase 1, all subjects received 500 mg of ciprofloxacin in combination with 200 mg of itraconazole twice daily for 7 days. Ciprofloxacin and itraconazole pharmacokinetics were studied and adverse effects noted.

RESULTS

Ciprofloxacin significantly increased the C(max) and AUC(0 - ∞) of itraconazole by 53.13% and 82.46%, respectively. The half-life and CL of itraconazole were not changed significantly. The combination of itraconazole and ciprofloxacin could therefore result in an increase in adverse drug reactions. Conversely, itraconazole had no significant effect on the pharmacokinetics of ciprofloxacin.

CONCLUSION

Ciprofloxacin decreases the metabolism of itraconazole, most likely through inhibition of CYP3A4. The dosage of itraconazole should be reduced and its therapeutic outcome should be monitored closely when these two agents are concomitantly administered.

Synthesis of some nucleosides derivatives from L- rhamnose with expected biological activity

Practical procedures for production of variously blocked compounds from L-rhamnose have been developed. These compounds are highly useful as indirect β-L-rhamnosyl donors. This approach represents a new method for the synthesis of aromatic nucleoside analogues and the synthesis of (3S, 4S, 5S, 6R) 3, 4, 5-triacetoxy-2-methyl-7,9-diaza-1-oxa-spiro [4,5]decane-10-one-8-thione (7).

Off-label drug use evaluation in paediatrics--applied to ciprofloxacin when used as treatment of cholangitis

PURPOSE

To evaluate drug and indication specific off-label use in paediatrics, applied to ciprofloxacin (CPFX) in cholangitis.

METHODS

We collected four different sets of data for an off-label drug use evaluation. (1) Literature review from medical journals, (2) the use and safety profile from the whole Swedish paediatric population by extracting data from national registers, (3) locally performed retrospective drug chart reviews, and (4) interviews regarding paediatric patients with CPFX treated cholangitis.

RESULTS

The literature reviews show a lack of information for paediatric use of CPFX in cholangitis. The prescribing of CPFX to Swedish children has grown over the last decade and generated a small number of reports for adverse drug reactions. In our local biliary atresia population 32 patients had suffered from at least one episode of cholangitis and 13 patients had been prescribed CPFX. The dosing strategy had an empirical prescribing approach, since monitoring of bacterial resistance and efficacy is difficult in the biliary ducts. No clear relationship was seen between dosing and age/weight. Reports of suspected side effects could not be found in the retrospective chart reviews. The interviews show that the existing dosage forms are well accepted.

CONCLUSIONS

This drug use evaluation creates awareness of the off-label situation. The international and national data are sparse for the paediatric use of CPFX in cholangitis. Locally we have highlighted a heterogeneous dosing strategy of CPFX, drug/drug interactions, and the need to monitor and report the risk of short- and long-term adverse drug reactions.

A novel antibiotic based long-term model of ovine smoke inhalation injury and septic shock

We modified our established and clinically relevant ARDS model of smoke inhalation injury and septic shock by administration of combined antibiotics (AB) such as piperacillin and ciprofloxacin, to more closely mimic the clinical intensive care setting. Twenty-three sheep were subjected to the injury, and allocated to four groups for a 96 h study period: sham (n=5 non-injured); control (n=6: injured); AB6h (n=6: injured, antibiotics started 6 h post-injury); AB12h (n=6: injured, antibiotics started 12 h post-injury). All sham animals survived 96 h. Control, AB6h, AB12h groups reached criteria of septic shock within 12 h post-injury. All controls died within 36 h. Eighty three percent of AB6h and fifty percent of AB12h survived 96 h. Median survival times were significantly improved in the treated groups compared with the control group: 24 h in control vs. 80.5 h in AB6h, and 65 h in AB12h animals. Combined ciprofloxacin and piperacillin therapy was effective, reduced nitric oxide production and mortality, and will allow future long-term studies in this model.

Preparation of ciprofloxacin-encapsulated poly(DL-lactide-co-glycolide) microspheres and its antibacterial activity

In this study, we created ciprofloxacin.HCl (CIP)-encapsulated poly(DL-lactide-co-glycolide) (PLGA) microspheres by the solvent evaporation method. Their antibacterial activity was evaluated with pathogenic microorganisms in vitro and in vivo. Since the half-life of CIP in the blood stream is short, sustained-release properties of microspheres may provide enhanced antibacterial activity. CIP-encapsulated microspheres of PLGA were prepared by the O/O method. CIP-encapsulated PLGA microspheres showed spherical shapes under a scanning electron microscope (SEM), and their particle sizes ranged from 10 to 50 microm. In an in vitro drug release study, CIP was continuously released over 3 weeks from the microspheres, and a burst effect was observed for the first 3 days. In the in vitro antibacterial activity test, CIP-microspheres showed lower antibacterial activity compared to free CIP because of their sustained-release properties, while empty microspheres did not affect the growth of microorganisms. In the in vivo antibacterial activity test, the number of microorganisms following treatment with CIP-encapsulated microspheres was significantly lower than after treatment with free CIP at 5 days postinjection. These results suggest that encapsulated CIP keeps its antibacterial activity after microencapsulation.

The administration of ciprofloxacin during continuous renal replacement therapy: pilot study

Continuous renal replacement therapy (CRRT) is a common technique in critically ill patients. However, there is no uniformity in the pharmacokinetics of ciprofloxacin (CPFX) used during CRRT. The aims of the present study were to estimate the pharmacokinetics of CPFX and to determine the appropriate administration of CPFX for critically ill patients undergoing CRRT. The pharmacokinetics of ciprofloxacin total clearance (CL(tot)) was calculated based on the creatinine clearance (CL(cre)), dialysate flow (QD), and ultrafiltrate flow (QF) as follows: CL(tot(L/h)) = (4.83 CL(cre(L/h)) + 6.41) + 0.92 (QD + Q(F(L/h))) based on in vitro study using CRRT circuit model. We administered CPFX to critically ill patients based on the CL(tot), which was 50 x CL(tot(L/h)) (mg/day). We confirmed that the CPFX concentrations reached higher than optimal concentrations, and infection was successfully controlled in these patients.

Ciprofloxacin or metronidazole for the treatment of perianal fistulas in patients with Crohn's disease: a randomized, double-blind, placebo-controlled pilot study

BACKGROUND

Although metronidazole and ciprofloxacin are used to treat perianal Crohn's disease (CD), no placebo-controlled trials have been performed.

METHODS

We performed a placebo-controlled pilot trial to evaluate the efficacy and safety of metronidazole and ciprofloxacin in patients with perianal CD. Twenty-five patients with CD and actively draining perianal fistulas were randomized to receive ciprofloxacin 500 mg, metronidazole 500 mg, or placebo twice daily for 10 weeks. Remission and response of perianal fistulas were defined as closure of all fistulas and closure of at least 50% of fistulas that were draining at baseline, respectively. The primary endpoint was remission at 10 weeks.

RESULTS

Ten patients were randomized to ciprofloxacin, 7 to metronidazole, and 8 to placebo. Remission at week 10 occurred in 3 patients (30%) treated with ciprofloxacin, no patients (0%) treated with metronidazole, and 1 patient (12.5%) treated with placebo (P = 0.41). Response at week 10 occurred in 4 patients (40%) treated with ciprofloxacin, 1 patient (14.3%) treated with metronidazole, and 1 patient (12.5%) treated with placebo (P = 0.43). Termination of the trial prior to week 10 occurred in 1 patient (10%) treated with ciprofloxacin, 5 patients (71.4%) treated with metronidazole, and 1 patient (12.5%) treated with placebo (P < 0.02). No serious adverse events occurred.

CONCLUSION

Remission and response occurred more frequently in patients treated with ciprofloxacin but the differences were not significant in this pilot study. Ciprofloxacin was well tolerated.

Clinical pharmacology of methadone for pain

BACKGROUND

This topical review addresses methadone's pharmacology, its application in malignant and non-malignant pain conditions, practical issues related to methadone for the treatment of pain and its influence on QTc time.

METHODS

Relevant papers were identified in PubMed and EMBASE.

RESULTS

Methadone is advocated by experts as a second line opioid when first line opioids fail to provide a satisfactory balance between pain control and side effects (opioid switching). Although randomized-controlled studies are lacking, current evidence suggests that switching to methadone in this situation reduces pain intensity. However, interindividual variability in its pharmacokinetics make its application challenging and metabolism by CYP 3A4 and 2B6 implies a substantial risk of drug-drug interactions. Several ways of switching to methadone have been presented, with a gradual switch during 3 days or 'stop and go' as the dominating strategies. Episodes of torsade de pointes arrhythmia during methadone treatment have been reported in patients with other risk factors for arrhythmia, while small prospective studies have reported a small, lasting and stable increase in QTc time. The extensive use of methadone for opioid replacement in addicts has added additional patient barriers to its use for pain control.

CONCLUSION

In spite of challenges related to the variable pharmacokinetics and concerns regarding increase in QTc time, current evidence indicates that opioid switching to methadone improves pain control in a substantial proportion of patients who are candidates for opioid switching. Measures must be instituted to secure that patients receiving methadone for pain are not considered opioid addicts.

Pharmacokinetic interaction of ketoconazole and itraconazole with ciprofloxacin

The effect of the concomitant administration of the antifungal drugs ketoconazole (KTC) and itraconazole (ITC) on the pharmacokinetics of ciprofloxacin (CIP) following short- and long-term administration in mice was investigated. Animals received either a dose of CIP (20 mg/kg, i.p.), CIP (20 mg/kg, i.p.) together with KTC (50 mg/kg, p.o.) or CIP (20 mg/kg, i.p.) and ITC (30 mg/kg, p.o.). The same treatments were repeated for 7 days. Blood samples were collected up to 4 h following drug administration and two urine samples were collected at 2 h and 4 h after drug administration. CIP plasma concentrations were significantly higher in KTC- and ITC-treated groups compared with the corresponding control groups. The concomitant administration of KTC or ITC with CIP also significantly (p<0.05) increased C(max), t(1/2), MRT and AUC(0-infinity) with no change in T(max). CIP clearance was significantly reduced by both agents. KTC and ITC reduced CIP urinary excretion. This study suggests that an important pharmacokinetic interaction between CIP and KTC or ITC is likely to occur when either of the two antifungal drugs is administered concomitantly with CIP. The results may suggest possible reductions in total clearance of CIP, owing to inhibition of its renal tubular excretion by KTC and ITC.