Study Design and Oversight

This cohort study was conducted on a subset of patients who achieved clinical improvement from the multicenter, placebo-controlled, double-blind phase 2 randomized clinical trial involving patients with moderate to severe PN.²⁰ The trial was conducted according to the principles of the Declaration of Helsinki,²³ and the protocol was approved by ethics committees at each participating institution, and patients provided written informed consent. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.