The Study of Brave-LC LDN Treatment Trial

This is a randomized, double-blind, placebo-controlled Phase 3 trial evaluating the efficacy and safety of a 16-week course of low-dose naltrexone (LDN) in approximately 1,300 participants aged 6 to 25 years with fatigue associated with Long COVID. Participants will be enrolled across three age cohorts (6-11, 12-17, and 18-25 years) and randomized 1:1 to receive LDN capsules or matching placebo capsules. LDN will be initiated at 1.5 mg daily and titrated weekly to a maximum tolerated dose of up to 4.5 mg daily. Randomization will be stratified by age cohort, and participants will also be randomized to a pharmacokinetic (PK) sampling window. Primary objective is to compare the change in fatigue severity from baseline to 16 weeks between participants aged 6 to 25 years with Long COVID randomized to a 16-week course of LDN or placebo. Secondary objectives: To compare the change in fatigue severity from baseline to 16 weeks between participants with Long COVID in age groups: 6 to 11 years, 12 to 17 years and 18-25 years. Each participant will be randomized to a 16-week course of LDN or placebo.