A Study to Assess the Safety and Efficacy of LB-P8 in Patients With PSC

This is phase 2, randomized, double-blind, placebo-controlled, multicenter study to assess the safety and efficacy of LB-P8 in adult patients with primary sclerosing cholangitis(PSC). * Part 1 will evaluate safety and tolerability of 2 pre-selected dose level of LB-P8 (low-dose\[1×10\^10 CFU/capsule\] and high dose \[1×10\^11 CFU/capsule\]) in adult patients with PSC. Part 1 plans to enroll a maximum number of 12 patients based on a "3+3" study design. * Part 2 will evaluate safety and efficacy in adult patients with PSC. Eligible patients with PSC will be randomized in a 1:1:1 ratio to receive treatment with low-dose LB-P8(1×10\^10 CFU/capsule), high-dose LB-P8(1×10\^11 CFU/capsule) or matched placebo capsule. Part 2 plans to enroll and randomize 75 patients to obtain 60 evaluable patients.