Pharmacokinetics of cyclophosphamide in patients with systemic necrotizing angiitis

Ovarian protection in cyclophosphamide-treated mice by fennel

•

Morphological parameters (WVD) in CP-treated groups significantly reduced.

•

Female sexual hormones in CP-treated groups significantly decreased.

•

CP-treatment lead to a reduction in the number of different ovarian follicles.

•

Fennel extract significantly ameliorate cyclophosphamide ovarian damages.

Evaluation of protective effect of fennel on mouse ovary against the destructive effects of cyclophosphamide (CP) was the aim of this study. Adult female NMARI mice were randomly divided into six groups (n = 8): (A) negative control, (B) CP200 mg/kg, (C) fennel 400 mg/kg/day, (E, F, and D) that received fennel 200, 400 and 100 mg/kg/day respectively + CP200 mg/kg. Their ovary weight, volume, and diameter (WVD) were measured. Five micron sections were stained using the H&E method. The serum levels of oestrogen and progesterone were measured using ELISA kit. The results showed that WVD significantly reduced in the CP-treated groups in comparison with the A and C, but WVD increased after treatment of the mice with fennel extract, in comparison with B group. A significant decrease of serum in terms of oestrogen and progesterone levels among CP-treated groups in comparison with the A group was observed. In the CP-treated groups a reduction in the number of different ovarian follicles in comparison with the A and C groups was observed. However, in the treated animals with fennel extract, these parameters significantly increased in comparison with the B group. Finally, it is concluded that fennel can protect ovary from cyclophosphamide side effects.

Impact of glomerular kidney diseases on the clearance of drugs

Numerous physiologic variations, including urinary protein excretion, low serum albumin concentrations, and reductions in kidney function (clearance), exist in patients with glomerulonephritis. These factors could alter the disposition of numerous drugs. The purpose of the current article was to review the influence of glomerulonephritis on the pharmacokinetics of drugs used clinically or experimentally in the treatment of these conditions. Several articles or presentations were located that reported on the pharmacokinetics of immunosuppressant, cytotoxic, and therapeutic antibody drugs in populations with glomerulonephritis. Most publications reported an increase in systemic clearance in glomerulonephritis as compared with populations in whom the drugs were typically used and in patients with nonglomerular forms of chronic kidney disease. It appears that the increase in systemic clearance is predominantly through nonrenal clearance pathways, although enhancement of renal clearance has also been appreciated for some drugs. Available preliminary data suggest specific alterations in the activity of individual pathways of drug metabolism and transport. Recommendations are provided for the design of future studies of drugs in the glomerulonephritis population and for inclusion of patients with urinary protein excretion in studies that assess drug pharmacokinetics.

Clinical pharmacokinetics of cyclophosphamide

Cyclophosphamide is an extensively used anticancer and immunosuppressive agent. It is a prodrug undergoing a complicated process of metabolic activation and inactivation. Technical difficulties in the accurate determination of the cyclophosphamide metabolites have long hampered the assessment of the clinical pharmacology of this drug. As these techniques are becoming increasingly available, adequate description of the pharmacokinetics of cyclophosphamide and its metabolites has become possible. There is incomplete understanding on the role of cyclophosphamide metabolites in the efficacy and toxicity of cyclophosphamide therapy. However, relationships between toxicity (cardiotoxicity, veno-occlusive disease) and exposure to cyclophosphamide and its metabolites have been established. Variations in the balance between metabolic activation and inactivation of cyclophosphamide owing to autoinduction, dose escalation, drug-drug interactions and individual differences have been reported, suggesting possibilities for optimisation of cyclophosphamide therapy. Knowledge of the pharmacokinetics of cyclophosphamide, and possibly monitoring the pharmacokinetics of cyclophosphamide in individuals, may be useful for improving its therapeutic index.

Pharmacokinetics of cyclophosphamide (CP) and 4-OH-CP/aldophosphamide in systemic vasculitis

Cyclophosphamide given in association with corticosteroids has markedly improved the prognosis of systemic vasculitis. Little information has been reported on cyclophosphamide pharmacokinetics in these diseases and data evaluating its metabolite, 4-hydroxycyclophosphamide/aldophosphamide, pharmacokinetics and concentrations are lacking. Cyclophosphamide was administered as a 1-h intravenous infusion every 3 weeks for six cycles to ten vasculitis patients. Serum cyclophosphamide and 4-hydroxycyclophosphamide/aldophosphamide concentrations were assayed on the first cycle of the treatment by reversed-phase high-pressure liquid chromatography with ultraviolet detection. The mean (+/- SD) 4-hydroxycyclophosphamide/aldophosphamide and cyclophosphamide areas under the serum concentration-time curves were, respectively, 1.86 +/- 1.12 and 154.1 +/- 62.7 mg/L x h with a ratio of 1.30 +/- 0.76%. The mean maximum serum 4-hydroxycyclophosphamide/aldophosphamide was reached 2.3 h after cyclophosphamide administration. The mean (+/- SD) cyclophosphamide and 4-hydroxycyclophosphamide/aldophosphamide half-lives were, respectively, 5.5 +/- 3.1 and 7.6 +/- 2.3 h. The results are consistent with those obtained for cancer patients, in spite of a wide interpatient variability of concentrations and pharmacokinetic parameters.