OXYBUTYNIN CHLORIDE (Page 2 of 4)

Pediatric

Pharmacokinetic information for pediatric patients 5 to 15 years of age with symptoms of detrusor overactivity associated with a neurological condition (e.g., spina bifida) is approved for Alza Corporation’s oxybutynin chloride extended release tablets. However, due to Alza Corporation’s marketing exclusivity rights, this drug product is not labeled for pediatric use.

Gender

There are no significant differences in the pharmacokinetics of oxybutynin in healthy male and female volunteers following administration of oxybutynin chloride extended release tablets.

Race

Available data suggest that there are no significant differences in the pharmacokinetics of oxybutynin based on race in healthy volunteers following administration of oxybutynin chloride extended release tablets.

Renal Insufficiency

There is no experience with the use of oxybutynin chloride extended release tablets in patients with renal insufficiency.

Hepatic Insufficiency

There is no experience with the use of oxybutynin chloride extended release tablets in patients with hepatic insufficiency.

Drug-Drug Interactions

See PRECAUTIONS: Drug Interactions.

CLINICAL STUDIES

Oxybutynin chloride extended release tablets were evaluated for the treatment of patients with overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency in three controlled studies and one open-label study. The majority of patients were Caucasian (89.0%) and female (91.9%) with a mean age of 59 years (range, 18 to 98 years). Entry criteria required that patients have urge or mixed incontinence (with a predominance of urge) as evidenced by ≥ 6 urge incontinence episodes per week and ≥ 10 micturitions per day. Study 1 was a fixed-dose escalation design, whereas the other studies used a dose-adjustment design in which each patient’s final dose was adjusted to a balance between improvement of incontinence symptoms and tolerability of side effects. Controlled studies included patients known to be responsive to oxybutynin or other anticholinergic medications, and these patients were maintained on a final dose for up to 2 weeks.

The efficacy results for the three controlled trials are presented in the following tables and figures.

Number of Urge Urinary Incontinence Episodes Per Week

Study 1	N	Oxybutynin Cl ER Tablets	N	Placebo
* Covariate adjusted mean with missing observations set to baseline values † The difference between Oxybutynin Chloride ER Tablets and placebo was statistically significant.
Mean Baseline	34	15.9	16	20.9
Mean (SD) Change from Baseline *	34	-15.8 (8.9)	16	-7.6 (8.6)
95% Confidence Interval for Difference	(-13.6,-2.8)†
(Oxybutynin Chloride ER Tablet- Placebo)

Study 2	N	Oxybutynin Cl ER Tablets	N	Oxybutynin
* Covariate adjusted mean with missing observations set to baseline values
Mean Baseline	53	27.6	52	23.0
Mean (SD) Change from Baseline *	53	-17.6 (11.9)	52	-19.4 (11.9)
95% Confidence Interval for Difference	(-2.8, 6.5)
(Oxybutynin Chloride ER Tablet- Oxybutynin)

Study 3	N	Oxybutynin Cl ER Tablets	N	Oxybutynin
* Covariate adjusted mean with missing observations set to baseline values † The difference between oxybutynin chloride ER tablets and oxybutynin fulfilled the criteria for comparable efficacy.
Mean Baseline	111	18.9	115	19.5
Mean (SD) Change from Baseline *	111	-14.5 (8.7)	115	-13.8 (8.6)
95% Confidence Interval for Difference	(-3.0, 1.6)†
(Oxybutynin Chloride ER Tablet- Oxybutynin)

OXYBUTYNIN CHLORIDE Indications and Usage

Oxybutynin chloride extended release tablets are once-daily controlled-release tablets indicated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency.

Pediatric use information for the treatment of patients aged 6 years and older with symptoms of detrusor overactivity associated with a neurological condition (e.g., spina bifida) is approved for Alza Corporation’s oxybutynin chloride extended release tablets. However, due to Alza Corporation’s marketing exclusivity rights, this drug product is not labeled for pediatric use.