Orally Administered ENT-01 for Parkinson's Disease-Related Constipation (KARMET)

This study will be conducted as a multi-center, randomized, double-blind, placebo-controlled study. Approximately 72 patients will be randomized 3:1 to treatment or placebo, with approximately 54 patients allocated to receive the active investigational product and approximately 18 patients allocated to receive placebo. \- Study Update- Amendment 3 - In this amendment, an additional 80 patients (approximately) will be randomized 1:1 to treatment or placebo (double-blind) with approximately 40 subjects allocated to each group.