A Study to Assess the Safety, Tolerability, and Pharmacology of Darifenacin in Patients With ALS

During the first two weeks (titration period), patients in the treatment arm will receive a daily dose of 7.5 mg darifenacin extended-release tablet. After the titration period, the dose will be increased to 15 mg once daily, which consists of two 7.5 mg tablets together for a period of 22 weeks.

During the first two weeks (titration period), patients in the placebo arm will receive a daily dose of 1 placebo tablet. After the titration period, the dose will be increased to two placebo tablets taken together, for a period of 22 weeks.