ART-001

This is a phase 3, double-blind, randomized, placebo-controlled, parallel group, adaptive, multicenter study planned to be conducted at multiple sites in North America, Canada, Taiwan and South Korea.
The purpose of this study is to measure the efficacy and safety of KP-001 compared with placebo in patients aged ≥2 years with common VM, common LM, or KTS/CLOVES syndrome.
An independent data monitoring committee (DMC) will be established to determine whether to discontinue or continue the study. It will also determine the redesign of the number of cases based on the result of the interim analysis.
The study will comprise the following:
* Screening Period: Up to 42 days prior to the first dose of study intervention.
* Treatment Period 1: This is a double-blind period in which KP-001 100 mg (or lower dose depending on their body weight) or placebo will be administered to patients once daily after breakfast until Week 24.
* Treatment Period 2: After 24 weeks of double blind treatment, all patients will switch to the KP-001 open label extension and treated up to Week 52.
* Follow-up Visit: This visit will occur 30 days after the last dose of study intervention, and assessments will be performed per the SoA.
* Discontinuation Visit: Patients who discontinue study intervention will be requested to continue participating in the study and assessments will be performed per the SoA. If the patients request to withdraw from the study, all tests and evaluations when possible will be performed at Discontinuation visit.