Randomized controlled trial of colchicine add on to the standard therapy in moderate and severe corona virus Disease-19 infection

Background: COVID19 complications cause inflammatory storm. Colchicine is a potent anti-inflammatory medication that has been proposed as a possible treatment option for COVID-19. Objective: to assess effectiveness and safety of add on use of colchicine to the standard treatment in moderate and severe COVID-19. Patients and methods: In this randomized controlled open label clinical trial, 160 patients hospitalized equally divided between moderate and severe COVID19 categories were randomized to 4 study groups in a 1:1:1:1 allocation (n = 40 for each group) according to type of treatment. Patients were randomly assigned to receive the standard treatment for 14 days (control group) or colchicine add on to the standard treatment 1 mg daily orally for 7 days then 0.5 mg daily for another 7 days. Survival rate, time to cure in days, and side effects were assessed. Results: Colchicine add on treatment was associated with a significantly shorter time to cure (referring to start of first symptom) by an average of 5 days in severe disease and 2 days in moderate disease (log-rank P=<0.001). In addition, the Colchicine add on significantly increased the risk of cure per unit of time by 2.69 times compared to controls after adjusting for disease severity, age, and time since the start of the disease to start of treatment. A severe COVID19 disease, a longer time for starting treatment, and the older age notably reduced the risk of cure (HR = 0.72, p = 0.07; HR = 0.74, p < 0.001; and HR = 0.59, p = 0.015 respectively). Possible side effects reported due to colchicine were 8/40 (20%) of severe COVID19 patients and 3/40 (7.5%) of moderate COVID19, non of which warranted stopping treatment by the data monitoring board. Generally, the side effects were 8/11 (72.73%) gastrointestinal disturbances. No immediate or late allergic reactions were observed. Conclusions: Colchicine add on treatment reduced significantly time to recovery in severe COVID19 (by five days) and in moderate cases (by two days) but did not lower the death rate. Side effects were mild, well tolerated and confined to gastrointestinal adverse events.