Pharmacokinetics and safety of a single oral dose of once-daily alfuzosin, 10 mg, in male subjects with mild to severe renal impairment

[Lower urinary tract symptoms and urinary incontinence in renal transplant recipients and candidates: The French guidelines from CTAFU]

OBJECTIVE

To propose surgical recommendations for the management of lower urinary tract symptoms (LUTS) and urinary incontinence in kidney transplant recipients and candidates.

METHOD

Following a systematic approach, a review of the literature (Medline) was conducted by the CTAFU focusing on medical and surgical treatment of LUTS and urinary incontinence in kidney transplant recipients and candidates. References were assessed according to a predefined process to propose recommendations with levels of evidence.

RESULTS

Functional bladder capacity and bladder compliance are impaired during dialysis. LUTS, related to pre-kidney transplantion alterations, frequently improve spontaneously after kidney transplantation. LUTS secondary to benign prostatic hyperplasia (BPH) may be underestimated before kidney transplantation due to oliguria, low bladder compliance and low bladder capacity. In LUTS associated with BPH, anticholinergics require dosage adjustment with creatinine clearance. If surgery is indicated after kidney transplantation, procedure can be safely performed in the early post-transplant course after removal of ureteral stent. Surgical management of urinary incontinence does not seem to be associated with an icreased risk for infectious complications in kidney transplant recipients. Particular attention should be paid to the management of postvoid residual and bladder pressures in case of neurological bladder disease. Optimal care of neurological bladder should be provided prior to transplantation: with a cautious management, and despite an increased occurrence of febrile urinary tract infections, transplant survival is not compromised.

CONCLUSION

These recommendations must contribute to improve the management of lower urinary tract symptoms and urinary incontinence in kidney transplant patients and kidney transplant candidates.

Medication burden and inappropriate prescription risk among elderly with advanced chronic kidney disease

BACKGROUND

Elderly patients with chronic kidney disease (CKD) frequently present comorbidities that put them at risk of polypharmacy and medication-related problems. This study aims to describe the overall medication profile of patients aged ≥75 years with advanced CKD from a multicenter French study and specifically the renally (RIMs) and potentially inappropriate-for-the-elderly medications (PIMs) that they take.

METHODS

This is a cross-sectional analysis of medication profiles of individuals aged ≥75 years with eGFR < 20 ml/min/1.73 m2 followed by a nephrologist, who collected their active prescriptions at the study inclusion visit. Medication profiles were first analyzed according to route of administration, therapeutic classification. Second, patients were classified according to their risk of potential medication-related problems, based on whether the prescription was a RIM or a PIM. RIMs and PIMs have been defined according to renal appropriateness guidelines and to Beer's criteria in the elderly. RIMs were subclassified by 4 types of category: (a) contraindication; (b) dose modification is recommended based on creatinine clearance (CrCl); (c) dose modification based on CrCl is not recommended but a maximum daily dose is mentioned, (d) no specific recommendations based on CrCl: "use with caution", "avoid in severe impairment", "careful monitoring of dose is required" "reduce the dose".

RESULTS

We collected 5196 individual medication prescriptions for 556 patients, for a median of 9 daily medications [7-11]. Antihypertensive agents, antithrombotics, and antianemics were the classes most frequently prescribed. Moreover, 77.0% of patients had at least 1 medication classified as a RIM. They accounted 31.3% of the drugs prescribed and 9.25% was contraindicated drugs. At least 1 PIM was taken by 57.6 and 45.5% of patients had at least one medication classified as RIM and PIM. The prescriptions most frequently requiring reassessment due to potential adverse effects were for proton pump inhibitors and allopurinol. The PIMs for which deprescription is especially important in this population are rilmenidine, long-term benzodiazepines, and anticholinergic drugs such as hydroxyzine.

CONCLUSION

We showed potential drug-related problems in elderly patients with advanced CKD. Healthcare providers must reassess each medication prescribed for this population, particularly the specific medications identified here.

TRIAL REGISTRATION

NCT02910908.

The Effects of CKD on Cytochrome P450-Mediated Drug Metabolism

CKD affects a significant proportion of the world's population, and the prevalence of CKD is increasing. Standard practice currently is to adjust the dose of renally eliminated medications as kidney function declines in effort to prevent adverse drug reactions. It is increasingly becoming recognized that CKD also impacts nonrenal clearance mechanisms such as hepatic and intestinal cytochrome P450 (CYP) enzymes and drug transport proteins, the latter of which is beyond the scope of this review. CYPs are responsible for the metabolism of many clinically used drugs. Genetics, patient factors (eg, age and disease) and drug interactions are well known to affect CYP metabolism resulting in variable pharmacokinetics and responses to medications. There now exists an abundance of evidence demonstrating that CKD can impact the activity of many CYP isoforms either through direct inhibition by circulating uremic toxins and/or by reducing CYP gene expression. Evidence suggests that reductions in CYP metabolism in ESRD are reversed by kidney transplantation and temporarily restored via hemodialysis. This review summarizes the current understanding of the effects that CKD can have on CYP metabolism and also discusses the impact that CYP metabolism phenotypes can have on the development of kidney injury.

Current understanding of drug disposition in kidney disease

Patients with chronic kidney disease (CKD) represent 13% of the American population. CKD has been shown to significantly alter drug disposition of nonrenally eliminated drugs. Indeed, modifications in the expression and function of intestinal and hepatic drug metabolism enzymes and uptake and efflux transporters have been reported. Uremic toxins, inflammatory cytokines, and parathyroid hormone have been implicated as causes. These changes can have an important clinical impact on drug disposition and lead to unintended toxicity if they are administered without dose adjustment in patients with impaired kidney function. This review summarizes recent preclinical and clinical studies and presents the current understanding of the effect of CKD on drug absorption, distribution, metabolism, and excretion.

Extended-release alfuzosin hydrochloride: A new alpha-adrenergic receptor antagonist for symptomatic benign prostatic hyperplasia

BACKGROUND

Extended-release (ER) alfuzosin hydrochloride is the most recently approved alpha-adrenergic receptor antagonist (AARA) for the management of symptomatic benign prostatic hyperplasia (BPH). Although new to the United States, alfuzosin has been available in immediate-release (IR) and sustained-release (SR) formulations in other countries for many years.

OBJECTIVE

This article reviews data on the pharmacodynamics, pharmacokinetics, efficacy, tolerability, drug-interaction potential, and dosing of alfuzosin ER.

METHODS

Relevant articles were identified through MEDLINE, EMBASE, and International Pharmaceutical Abstracts searches of the English-language literature published between 1986 and September 2003 using the terms alfuzosin, alpha-adrenergic receptor antagonists, and quinazolines. The reference lists of identified articles were also searched, as were abstracts from annual meetings of the American Urological Association for the past 5 years. Data regarding the ER formulation were emphasized, and data involving the IR/SR formulations were included only when data for the ER formulation were not available or as needed for clarification.

RESULTS

In comparative trials with its IR counterpart (alfuzosin ER 10 mg QD vs alfuzosin IR 2.5 mg TID), alfuzosin ER was an equieffective once-daily AARA. No comparative trials of alfuzosin ER with the SR (BID) formulation or with other AARAs were identified. Food has been found to exert a clinically important effect by enhancing the bioavailability of the ER formulation; thus, the drug should be taken on a full stomach. Hepatic impairment has been found to significantly delay the elimination of alfuzosin IF, which constitutes a contraindication to use of the ER formulation. Renal impairment does not appear to exert clinically important effects on the pharmacokinetics of alfuzosin ER. Adverse events with alfuzosin ER include dizziness, upper respiratory tract infection, headache, and fatigue, with hypotension and syncope reported rarely. Concurrent use of inhibitors of the cytochrome P450 3A4 isozyme (eg, ketoconazole, diltiazem, cimetidine, atenolol) can significantly elevate serum concentrations of alfuzosin and enhance its pharmacodynamic effects.

CONCLUSIONS

In the absence of direct head-to-head comparative trials, the role of alfuzosin ER in the management of symptomatic BPH relative to that of other AARAs is unclear. Because the effect size (drug response minus placebo response) of alfuzosin ER is comparable to that of other AARAs, marked differences in efficacy are unlikely. Extrapolating from direct comparative trials between these agents and alfuzosin IR/SR, alfuzosin ER would be expected to have better cardiovascular tolerability (eg, in terms of dizziness and orthostasis) than prazosin, terazosin, or doxazosin, and to have similar tolerability to tamsulosin. However, the existing data do not suggest that alfuzosin ER is likely to represent a significant advance over tamsulosin.