Effect of prucalopride on the pharmacokinetics of oral contraceptives in healthy women.

BACKGROUND: Prucalopride is a selective, high-affinity, 5-hydroxytryptamine 4 (5-HT4) receptor agonist, which is approved for the symptomatic treatment of chronic constipation in women in whom laxatives fail to provide adequate relief. Women of childbearing potential, many of whom will be using oral contraceptives, comprise a large proportion of patients seeking medical therapy for constipation. OBJECTIVE: The aim of this study was to evaluate the effect of prucalopride on the absorption and steady-state pharmacokinetics of oral contraceptives in healthy women. METHODS: Sixteen women (aged 18-45 years) were enrolled in this open-label, two-way crossover trial (ClinicalTrials.gov identifier: NCT01036893) and given two 5-day treatments with a once-daily oral contraceptive (ethinylestradiol 0.035 mg + norethisterone 1 mg), alone and in combination with prucalopride 2 mg once daily. Treatments were separated by a 7 ± 2-day washout period. On days 1 and 5, blood samples were obtained pre-dose and at regular intervals post-dose up to 24 and 48 hours, respectively, to determine ethinylestradiol and norethisterone plasma concentrations. Prucalopride plasma concentrations were determined pre-dose and 3 hours post-dose on days 1 and 5, and 24 hours post-dose on day 6. Safety was assessed. RESULTS: Thirteen participants completed the study. One participant was thought to be non-compliant on days 3 and/or 4, and was excluded from the day 5 analysis. On days 1 and 5, maximum plasma concentrations of both oral contraceptive constituents were attained in ~1 hour and were unaffected by prucalopride administration. On day 5, steady-state prucalopride and oral contraceptive concentrations had been achieved. Prucalopride did not affect the pharmacokinetics of the oral contraceptives: point estimates for the maximum plasma concentration and area under the plasma concentration-time curve values and their associated 90 % confidence intervals were contained within predefined equivalence limits (80-125 %). Prucalopride was well tolerated, with a safety profile consistent with those observed in previous studies. CONCLUSION: Co-administration of prucalopride with an oral contraceptive did not result in any clinically meaningful pharmacokinetic interactions and was well tolerated.

Effect of renal impairment on the pharmacokinetics of prucalopride: a single- dose open-label Phase I study.

OBJECTIVE: To evaluate the pharmacokinetics of prucalopride in individuals with renal impairment (RI). METHODS: This open-label Phase I study (ClinicalTrials.gov identifier: NCT01674192) enrolled men and women aged 18-75 years who were classified by renal function: normal renal function (creatinine clearance ≥ 80 mL/min/1.73 m²), mild RI (50-79 mL/min/1.73 m²), moderate RI (25-49 mL/min/1.73 m²), and severe RI (≤ 24 mL/min/1.73 m²). All received a single oral dose of prucalopride 2 mg. RESULTS: Thirty-four individuals (normal renal function: 10; mild RI: 8; moderate RI: 7; severe RI: 9) received prucalopride. In all groups, maximum plasma concentration was reached within 2-4 hours. There was no significant difference in exposure (area under the plasma concentration-time curve from time zero to infinity) between participants with mild RI and those with normal renal function. However, area under the plasma concentration-time curve from time zero to infinity values were 1.5- and 2.3-fold higher (P = 0.002 and P < 0.001) in patients with moderate RI and severe RI, respectively, than in those with normal renal function. The proportion of total body clearance accounted for by renal clearance was significantly reduced in those with RI. CONCLUSION: Clinically meaningful reductions in renal clearance were seen in participants with severe RI, which supports a decrease from the standard dose of prucalopride 2 mg daily to 1 mg daily in these individuals.

Absence of an active metabolite for the triazole antifungal pramiconazole.

Pramiconazole is an antifungal with high potential for the treatment of dermatophyte and yeast infections of the skin. It is currently not known whether pramiconazole is active alone as the parent agent or assisted by active metabolites. The in vitro metabolism as well as the metabolic stability of pramiconazole was investigated in subcellular liver fractions and isolated hepatocytes of several species. Results indicate that the metabolism of pramiconazole was slow, since the enzyme-mediated disappearance of pramiconazole was rather slow. To investigate whether pramiconazole was converted into an active metabolite in humans, serum samples from healthy volunteers receiving a daily dose of 100 or 200 mg pramiconazole for one week were assayed with an agar diffusion bioassay and liquid chromatography-tandem mass spectrometry. It was concluded that there was no active metabolite present in serum samples from healthy volunteers after oral dosing of pramiconazole.