Pharmacokinetics of panipenem/betamipron in patients with end-stage renal disease

Recent updates of carbapenem antibiotics

Carbapenems are among the most commonly used and the most efficient antibiotics since they are relatively resistant to hydrolysis by most β-lactamases, they target penicillin-binding proteins, and generally have broad-spectrum antibacterial effect. In this review, we described the initial discovery and development of carbapenems, chemical characteristics, in vitro/in vivo activities, resistance studies, and clinical investigations for traditional carbapenem antibiotics in the market; imipenem-cilastatin, meropenem, ertapenem, doripenem, biapenem, panipenem/betamipron in addition to newer carbapenems such as razupenem, tebipenem, tomopenem, and sanfetrinem. We focused on the literature published from 2010 to 2016.

Population Pharmacokinetic Analysis of Panipenem/Betamipron in Patients with Various Degrees of Renal Function

BACKGROUND

Although plasma concentrations of panipenem were elevated and the risk of adverse events would increase in patients with renal impairment, a precise dosage regimen for patients with renal impairment has not been established.

METHODS

Population pharmacokinetic analyses were performed with plasma concentrations from 26 healthy volunteers and 41 patients. Optimal dosage regimens for patients with renal impairment were determined based on the bacteriostatic index of C(20%T)>(MIC), the concentration corresponding to the time above MIC of 20% of the dosing interval.

RESULTS

The clearance of panipenem and betamipron was correlated with creatinine clearance and the volume of the distribution of panipenem was correlated with body weight. C(20%T)>(MIC) for a standard dosage regimen of panipenem was 4.3 microg/ml, and the optimal dosage regimen for the patients was established based on this value.

CONCLUSION

The dosage regimen of panipenem for patients with renal impairment should be reduced when creatinine clearance is lower than 60 ml/min.

Prediction of Pharmacokinetics of Antibiotics in Patients with End-Stage Renal Disease

A novel and convenient method to predict the pharmacokinetics of several kinds of antibiotic agents in patients with end-stage renal disease (ESRD) was examined based on the in vitro extraction ratios and pharmacokinetic parameters in healthy volunteers. The dializability of 17 antibiotic agents in 4% human serum albumin solution were determined using a high-performance hemodialytic membrane for clinical use. We assumed that the off-hemodialysis clearance approximated the non-renal clearance, while the on-hemodialysis clearance was considered to be sum of the off-hemodialysis clearance and the hemodialytic clearance. The estimated on- and off-hemodialysis clearances were compared with the ones observed in ESRD patients. In order to confirm the method prospectively, an in vivo pharmacokinetic study was performed in dogs with mercury chloride-induced experimental renal failure. The in vitro extraction ratios of 9 beta-lactams were broadly ranged from 10.9 to 75.6% depending on their physicochemical properties. In contrast, those of the other antibiotics were consistent with their chemical classes: 60.5-63.2% for fluoroquinolone, 48.8-51.1% for aminoglycoside and 18.7-25.6% for glycopeptide. Both the estimated on- and off-hemodialysis clearances of the 17 antibiotics coincided well with the observed values in the literature, regardless of their physicochemical and pharmacokinetic properties. The validity and applicability of this method to three cefems, cefmetazole, cefotaxime and cefoperazone, was prospectively confirmed in the animal study. In conclusion, this new method enables the prediction of the on- and off-hemodialysis clearances of several kinds of antibiotics in ESRD patients from minimal information of their pharmacokinetics in healthy subjects and their in vitro dializability.

Quantitative Evaluation of Effect of Renal Failure on the Pharmacokinetics of Panipenem in Rats

The pharmacokinetics of panipenem in experimental renal failure animal models was investigated in order to identify the appropriate covariates affecting the pharmacokinetic behavior. Panipenem and betamipron were administered intravenously to rats with a variety of renal failures, such as nephritis induced by glycerol, gentamicin, uranium and antiserum against glomerular basement membrane as well as 5/6 subtotal nephrectomy. Panipenem in plasma and urine was determined and pharmacokinetic analysis was performed using a one-compartment open model. The elimination half-life prolonged and total body clearance, renal clearance (CL(R)) and renal excretion ratio were decreased according to the renal function, i.e. control>glycerol>anti-GBM=gentamicin>nephrectomy=uranium in order. However, distribution volume was consistent in all models. CL(R) showed strong positive correlation with the glomerular filtration rate in spite of a weak correlation with the reciprocal of blood urea nitrogen. However, no obvious correlation was observed with secretory clearance of N-1-methylnicotinamide. This preliminary information based on animal model might be useful for designing pharmacokinetic studies in special population at early stage of new drug development.