Colchicine to reduce coronavirus disease-19-related inflammation and cardiovascular complications in high-risk patients post-acute infection with SARS-COV-2-a study protocol for a randomized controlled trial

Background: There is no known effective pharmacological therapy for long COVID, which is characterized by wide-ranging, multisystemic, fluctuating, or relapsing symptoms in a large proportion of survivors of acute COVID. This randomized controlled trial aims to assess the safety and efficacy of an anti-inflammatory agent colchicine, to reduce symptoms among those at high risk of developing long COVID.

Methods: This multi-centre, parallel arm, 1:1 individual randomized, placebo-controlled, double-blind superiority trial will enrol 350 individuals with persistent post-COVID symptoms. Participants will be randomized to either colchicine 0.5 mg once daily (< 70 kg) or twice daily (≥ 70 kg) or matched placebo for 26 weeks and will be followed up until 52 weeks after randomization. The primary trial objective is to demonstrate the superiority of colchicine over a placebo in improving distance walked in 6 min at 52 weeks from baseline. The secondary objectives are to assess the efficacy of colchicine compared to placebo with respect to lung function, inflammatory markers, constitutional symptoms, and mental health state. In a sub-sample of 100 participants, cardiac biomarkers of myocardial injury and myocardial oedema using MRI will be compared.

Discussion: Persistent inflammatory response following SARS-CoV-19 is one of the postulated pathophysiological mechanisms of long COVID. Colchicine, a low-cost anti-inflammatory agent, acts via multiple inflammatory pathways and has an established safety profile. This trial will generate evidence for an important health priority that can rapidly translate into practice.

Trial registration: This clinical trial has been registered prospectively on www.

Clinicaltrials: gov with registration CTRI/2021/11/038234 dated November 24, 2021.