After oral administration of VESIcare to healthy volunteers, peak plasma levels (Cmax) of solifenacin are reached within 3 to 8 hours after administration, and at steady state ranged from 32. 3 to 62. 9 ng/mL for the 5 and 10 mg VESIcare tablets, respectively.
The absolute bioavailability of solifenacin is approximately 90%, and plasma concentrations of solifenacin are proportional to the dose administered. Distribution Solifenacin is approximately 98% (in vivo) bound to human plasma proteins. Solifenacin is highly distributed to non-CNS tissues, having a mean steady-state volume of distribution of 600L. Metabolism.
Solifenacin is extensively metabolized in the liver. The primary pathway for elimination is by way of CYP3A4; however, alternate metabolic pathways exist. The primary metabolic routes of solifenacin are through N-oxidation of the quinuclidin ring and 4R-hydroxylation of tetrahydroisoquinoline ring.
One pharmacologically active metabolite (4R-hydroxy solifenacin), occurring at low concentrations and unlikely to contribute significantly to clinical activity, and three pharmacologically inactive metabolites (N-glucuronide and the N-oxide and 4R-hydroxy-N-oxide of solifenacin) have been found in human plasma after oral dosing.
Excretion Following the administration of 10 mg of 14C-solifenacin succinate to healthy volunteers, 69. 2% of the radioactivity was recovered in the urine and 22. 5% in the feces over 26 days. Less than 15% (as mean value) of the dose was recovered in the urine as intact solifenacin.
The major metabolites identified in urine were N-oxide of solifenacin, 4R-hydroxy solifenacin and 4R-hydroxy-N-oxide of solifenacin and in feces 4R-hydroxy solifenacin. The elimination half-life of solifenacin following chronic dosing is approximately 45-68 hours. 9. Therapeutic efficacy (Clinical trials): 2 studies 1.
Type of study: Fasting Design: Single-dose, parallel* in-vivo Strength: 10 mg Subjects: Normal healthy males and females, general population Additional comments: Females should not be pregnant or lactating, and if applicable, should practice abstention or contraception during the study. * Note: As an option, you may conduct this study using a single dose, two-way crossover design. As an additional option for either the crossover or parallel design, you may truncate the AUC at 72 hours, provided the drug demonstrates low intrasubject variability in distribution and clearance. 2. Type of Study: Fed.
Design: Single-dose, parallel* in-vivo Strength: 10 mg Subjects: Normal healthy males and females, general population 10. Comparison with other therapies and/or other drugs: In a study patients were randomised to receive either solifenacin 5 mg or 10 mg once daily, tolterodine 2 mg twice daily or placebo for 12 weeks. This study did not demonstrate that solifenacin is clinically superior to tolterodine. 11. Adverse Effects: The most common side effects of VESIcare include:
Serious allergic reaction dry mouth constipation. Call your doctor if you become constipated for 3 or more days. urinary tract infection blurred vision heat exhaustion or heat-stroke. This can happen when VESIcare is used in hot environments. 12. Drug interactions: Inhibitors of CYP3A4 may increase the concentration of VESIcare. Inducers of CYP3A4 may decrease the concentration of VESIcare. 13. Contraindications:
Urinary retention Gastric retention Uncontrolled narrow-angle glaucoma In patients who have demonstrated hypersensitivity to the drug 14. Warning and precautions: Angioedema and Anaphylactic Reactions Angioedema of the face, lips, tongue, and/or larynx have been reported with solifenacin. In some cases angioedema occurred after the first dose.
Cases of angioedema have been reported to occur hours after the first dose or after multiple doses. Angioedema associated with upper airway swelling may be life threatening. If involvement of the tongue, hypopharynx, or larynx occurs, solifenacin should be promptly discontinued and appropriate therapy and/or measures necessary to ensure a patent airway should be promptly provided.
Anaphylactic reactions have been reported rarely in patients treated with solifenacin succinate. Solifenacin succinate should not be used in patients with a known or suspected hypersensitivity to solifenacin succinate.
In patients who develop anaphylactic reactions, solifenacin succinate should be discontinued and appropriate therapy and/or measures should be taken. Urinary Retention VESIcare, like other anticholinergic drugs, should be administered with caution to patients with clinically significant bladder outflow obstruction because of the risk of urinary retention.
Gastrointestinal Disorders VESIcare, like other anticholinergics, should be used with caution in patients with decreased gastrointestinal motility. Controlled Narrow-Angle Glaucoma VESIcare should be used with caution in patients being treated for narrow-angle glaucoma. Hepatic Impairment VESIcare should be used with caution in patients with hepatic impairment.
Doses of VESIcare greater than 5 mg are not recommended in patients with moderate hepatic impairment (Child-Pugh B). VESIcare is not recommended for patients with severe hepatic impairment (Child-Pugh C). Renal Impairment VESIcare should be used with caution in patients with renal impairment.