A. Role of colchicine in COVID-19: Given the anti-inflammatory properties of colchicine, there was enthusiasm to study its effect on COVID-19. A recent retrospective cohort study showed colchicine use was associated with reduced mortality and faster recovery in COVID-19 patients.14
Another recent trial concluded that colchicine reduced the length of both oxygen therapy and hospitalization.15 The COLCORONA trial showed that, for non-hospitalized patients with COVID-19, colchicine reduced the composite rate of death or hospitalization.16 However, although the final results of the RECOVERY trial are yet to be published, the preliminary analysis of data failed to show a significant difference in the primary endpoint of 28-day mortality of colchicine vs. usual care alone.17
Multiple trials are in progress, as noted on clinicaltrials.gov.18
B. Cardiac conditions: Multiple in vitro animal models and observations in patients treated with colchicine have demonstrated that colchicine has antifibrotic effects and plays a role in improving endothelial dysfunction, inhibition of intimal hyperplasia, suppressing smooth muscle cell proliferation and reducing the expression of inflammatory proteins, such as TNF-α and NF-κB, among others.5 This encouraged investigations of colchicine’s role in pericarditis and atherosclerosis.
1. Colchicine proved efficacious in treating pericarditis when added to the conventional anti-inflammatory regimen.19
2. Interestingly, the COLCOT trial showed that treating patients with recent myocardial infarction with low-dose colchicine, 0.5 mg daily, significantly lowered the risk of ischemic cardiovascular events.20 However, the Australian COPS Randomized Clinical Trial did not replicate such a result and concluded the use of colchicine as secondary prevention after acute coronary syndrome was associated with an increased rate of mortality.21 Further studies are required to determine the safety and benefit of colchicine after a myocardial infarction.
C. Other arthritic conditions—calcium pyrophosphate (CPP) arthritis: Although minimal literature supports the use of colchicine in patients with CPP arthropathy, the shared mechanism of inflammation induced by CPP and urate crystals support the logic of its use.
In a randomized controlled trial of 39 patients with knee osteoarthritis with persistent inflammation induced by CPP, the addition of colchicine to intra-articular glucocorticoids was superior to intra-articular glucocorticoids alone.22
In another clinical trial among patients with knee osteoarthritis, the addition of colchicine to nimesulide was superior to nimesulide alone.
In 2011, EULAR recommended colchicine in patients with CPP arthropathy based on expert opinion.23
D. Dermatologic indications: Very limited data exist for the use of colchicine in dermatologic conditions, yet colchicine is used widely for a variety of dermatologic diseases, including several that rheumatologists frequently see. Neutrophilic dermatoses, such as Sweet’s syndrome, pyoderma gangrenosum and Behçet’s disease, as well as neutrophilic infiltrative diseases, such as pustular psoriasis, erythema nodosum, cutaneous vasculitis and recurrent aphthous stomatitis, have all been successfully treated with colchicine. It has also been used in neutrophilic bullous disorders, such as dermatitis herpetiformis, and other conditions, such as actinic keratosis and hidradenitis suppurativa. Some initial studies have also assessed the use of colchicine in scleroderma.24-27
Adverse Drug Reactions
Colchicine is a relatively well tolerated drug, with the most common side effect being diarrhea, which is noted in about 23% of patients receiving low to moderate doses. In patients using higher doses, more than 2–3 mg/day, the incidence of diarrhea could increase to about 80%. Other gastrointestinal side effects, such as nausea and vomiting, have also been noted.5,11
