Bladder-health diaries: an assessment of 3-day vs 7-day entries.

OBJECTIVES: To assess the reliability of symptom reports in 3-day vs 7-day bladder diaries used in clinical trials of patients with overactive bladder (OAB) and to compare those results and related issues with previous reports. MATERIALS AND METHODS: We analysed two large-scale, randomized, phase 3 clinical trials of the use of transdermal oxybutynin for treating patients with OAB. The first trial (Trial A, 520 patients) compared three doses of transdermal oxybutynin (1.3, 2.6 and 3.9 mg/day) with placebo. Patients documented their OAB symptoms in a 7-day diary. The second clinical study (Trial B, 361 patients) compared the efficacy of 3.9 mg/day transdermal oxybutynin with 4 mg/day extended-release tolterodine and with placebo; this trial required symptom recording for only 3 days. The internal consistency of the data from the 7-day trial was determined and then compared with the 3-day trial results. RESULTS: Patients on transdermal oxybutynin or long-acting tolterodine for their OAB symptoms showed a clinically and statistically significant improvement, results that were documented in both 3-day and 7-day bladder diaries. However, compared with 7-day symptom records, 3-day diaries were associated with significantly better compliance with record-keeping (P < 0.001). CONCLUSIONS: Seven-day diaries used in clinical trials supply accurate and reproducible data on clinical manifestations of OAB, but 3-day diaries are equally effective and have the potential for better accuracy through increased patient convenience. Three-day diaries may also reduce the tendency for patients to complete gaps in record-keeping from memory.

Pharmacokinetics, metabolism, and saliva output during transdermal and extended-release oral oxybutynin administration in healthy subjects.

OBJECTIVE: To compare the pharmacokinetics and adverse effect dynamics of 2 modified-release oxybutynin treatments. SUBJECTS AND METHODS: Between October 15 and November 6, 2001, 13 healthy subjects (7 men and 6 women) participated in a randomized, 2-way crossover study of transdermal (Oxytrol, 3.9 mg/d) and extended-release oral (Ditropan XL, 10 mg) oxybutynin. Multiple blood and saliva samples were collected. Pharmacokinetic parameters and total salivary output were assessed. Statistical analyses included 95% confidence intervals, paired t test, analysis of variance, and linear regression. RESULTS: Steady-state plasma concentrations were achieved after the first transdermal application and after the second extended-release oral dose. Mean +/- SD 24-hour oxybutynin areas under the concentration-time curve were comparable during transdermal and oral extended-release treatments, 10.8 +/- 24 vs 9.2 +/- 33 ng x h(-1) x mL(-1), respectively. However, the ratio of area under the curve (N-desethyloxybutynin/oxybutynin) after transdermal administration (1.2 +/- 03) was significantly lower (P < .001) than after extended-release oral administration (4.1 +/- 0.9). Mean plasma concentrations were less variable during transdermal compared with extended-release oral administration. Mean +/- SD saliva output was greater during transdermal than extended-release oral treatment (15.7 +/- 93 vs 12.2 +/- 6.8 g, respectively; P = .02). Lower N-desethyloxybutynin during transdermal application was associated with greater saliva output (r = -059, P = .04). No clinically important treatment-related adverse effects were observed. CONCLUSIONS: Transdermal oxybutynin administration results in greater systemic availability and minimizes metabolism to N-desethyloxybutynin compared with extended-release oral administration. Lower N-desethyloxybutynin plasma concentration and greater saliva output during transdermal treatment correspond to the reported low incidence of dry mouth in patients with overactive bladder.

Comparative efficacy and safety of transdermal oxybutynin and oral tolterodine versus placebo in previously treated patients with urge and mixed urinary incontinence.

OBJECTIVES: To compare the efficacy and safety of an oxybutynin transdermal delivery system (OXY-TDS) and oral, long-acting tolterodine (TOL-LA) with placebo in previously treated patients with urge or mixed urinary incontinence. METHODS: After withdrawal of their current antimuscarinic therapy, 361 adult patients were randomized to 12 weeks of double-blind, double-dummy treatment with twice weekly OXY-TDS 3.9 mg/day, daily TOL-LA 4 mg, or placebo. Evaluations included change from baseline in patient urinary diary symptoms, incontinence-specific quality of life, and safety. RESULTS: OXY-TDS 3.9 mg/day and TOL-LA 4 mg/day significantly reduced the number of daily incontinence episodes (median change -3 OXY-TDS and -3 TOL-LA versus -2 placebo; P <0.05), increased the average void volume (median change 24 and 29 mL versus 5.5 mL, P <0.01), and improved quality of life (incontinence impact questionnaire [IIQ] total score, P <0.05; Urogenital Distress Inventory Irritative Symptom subscale, P <0.05) compared with placebo. The most common adverse event for OXY-TDS was localized application site pruritus (14% versus 4% placebo) accompanied by a low incidence of systemic side effects (eg, dry mouth 4.1%). Anticholinergic adverse events occurred with greatest frequency during TOL-LA treatment (dry mouth 7.3% versus 1.7% placebo, P <0.05). CONCLUSIONS: OXY-TDS and TOL-LA are effective and comparable treatments for patients with urge and mixed incontinence. OXY-TDS improves systemic safety with regard to anticholinergic side effects. Local skin irritation occurs in some OXY-TDS patients.

Pharmacokinetics and metabolism of transdermal oxybutynin: in vitro and in vivo performance of a novel delivery system.

PURPOSE: The purpose of this work was to characterize in vitro/in vivo delivery and pharmacokinetics of oxybutynin (OXY) and its active metabolite. N-desethyloxybutynin (DEO), by a novel matrix transdermal system (TDS). METHODS: Two in vivo, randomized, three-way crossover trials examined single/multiple OXY TDS doses. Abdomen, buttock, and hip application sites were compared and dose proportionality was evaluated. Model independent pharmacokinetics, elimination rate constants, and metabolite/drug ratios were derived from both plasma OXY and DEO concentrations. RESULTS: Single/multiple applications of the OXY TDS to the abdomen yielded mean Cmax OXY concentrations of 3.4 +/- 1.1/6.6 +/- 2.4 ng/mL and median tmax of 36/10 h, with steady state achieved during the second application. Plasma OXY and DEO concentrations decreased gradually after Cmax until system removal. Buttock and hip applications resulted in bioequivalent OXY absorption. AUC ratios of DEO/OXY were 1.5 +/- 0.4 (single dose) and 1.3 +/- 0.3 (multiple dose). Mean in vitro OXY skin absorption (186 microg/h) was comparable to the estimated in vivo delivery (163 microg/h) over 96 h. CONCLUSIONS: Sustained delivery over 4 days and multiple sites allow a convenient, well-tolerated, twice-weekly OXY TDS dosing. A low incidence of anticholinergic side effects is expected during clinical use because of the avoidance of presystemic metabolism and low DEO plasma concentrations. The consistent delivery, absorption, and pharmacokinetics should result in an effective treatment of patients with overactive bladder.

Efficacy and safety of transdermal oxybutynin in patients with urge and mixed urinary incontinence.

PURPOSE: We evaluated the efficacy and safety of an oxybutynin transdermal delivery system (TDS) in a general population of patients with overactive bladder and urge or mixed urinary incontinence. MATERIALS AND METHODS: Following symptom stabilization or treatment withdrawal 520 adult patients were randomized to 12 weeks of double-blind daily treatment with 1.3, 2.6 or 3.9 mg. oxybutynin TDS or placebo administered twice weekly, followed by a 12-week open-label, dose titration period to assess efficacy and safety further. Evaluations included patient urinary diaries, incontinence specific quality of life and safety. RESULTS: A dose of 3.9 mg. daily oxybutynin TDS significantly reduced the number of weekly incontinence episodes (median change -19.0 versus -14.5, p = 0.0165), reduced average daily urinary frequency (mean change -2.3 versus -1.7, p = 0.0457), increased average voided volume (median change 24 versus 6 ml., p = 0.0063) and significantly improved quality of life (Incontinence Impact Questionnaire total score, p = 0.0327) compared with placebo. Average voided volume increased in the daily 2.6 mg. group (19 ml., p = 0.0157) but there were no other significant differences between 1.3 and 2.6 mg. oxybutynin TDS and placebo. The most common adverse event was application site pruritus (oxybutynin TDS 10.8% to 16.8%, placebo 6.1%). Dry mouth incidence was similar in both groups (7.0% versus 8.3%, p not significant). In the open-label period a sustained reduction of nearly 3 incontinence episodes per day was reported for all groups. CONCLUSIONS: Doses of 2.6 and 3.9 mg. oxybutynin TDS daily improve overactive bladder symptoms and quality of life, and are well tolerated. Transdermal oxybutynin is an innovative new treatment for overactive bladder.