Repurposing colchicine's journey in view of drug-to-drug interactions. A review

Colchicine: the good, the bad, the ugly and how to minimize the risks

Colchicine has an important role in managing various conditions, including gout, familial Mediterranean fever, amyloidosis, Behçet's syndrome, recurrent pericarditis and calcium pyrophosphate deposition disease. The adverse effect profile of colchicine is well understood. However, due to its narrow therapeutic index, colchicine has been associated with overdose and fatalities. When ingested in toxic amounts, the mainstay of management is supportive care. Strategies to minimize the risk of colchicine poisoning can focus on three broad causes: unauthorized access, intentional overdose and inappropriate dosing. Culturally safe and appropriate education about storage and appropriate use of colchicine is essential to minimize the risk of overdose.

Colchicine Drug Interaction Errors and Misunderstandings: Recommendations for Improved Evidence-Based Management

Colchicine is useful for the prevention and treatment of gout and a variety of other disorders. It is a substrate for CYP3A4 and P-glycoprotein (P-gp), and concomitant administration with CYP3A4/P-gp inhibitors can cause life-threatening drug-drug interactions (DDIs) such as pancytopenia, multiorgan failure, and cardiac arrhythmias. Colchicine can also cause myotoxicity, and coadministration with other myotoxic drugs may increase the risk of myopathy and rhabdomyolysis. Many sources of DDI information including journal publications, product labels, and online sources have errors or misleading statements regarding which drugs interact with colchicine, as well as suboptimal recommendations for managing the DDIs to minimize patient harm. Furthermore, assessment of the clinical importance of specific colchicine DDIs can vary dramatically from one source to another. In this paper we provide an evidence-based evaluation of which drugs can be expected to interact with colchicine, and which drugs have been stated to interact with colchicine but are unlikely to do so. Based on these evaluations we suggest management options for reducing the risk of potentially severe adverse outcomes from colchicine DDIs. The common recommendation to reduce the dose of colchicine when given with CYP3A4/P-gp inhibitors is likely to result in colchicine toxicity in some patients and therapeutic failure in others. A comprehensive evaluation of the almost 100 reported cases of colchicine DDIs is included in table form in the electronic supplementary material. Colchicine is a valuable drug, but improvements in the information about colchicine DDIs are needed in order to minimize the risk of serious adverse outcomes.

Treatment with COLchicine in hospitalized patients affected by COVID-19: The COLVID-19 trial

OBJECTIVE

To evaluate whether the addition of colchicine to standard of care (SOC) results in better outcomes in hospitalized patients with COVID-19.

DESIGN

This interventional, multicenter, randomized, phase 2 study, evaluated colchicine 1.5 mg/day added to SOC in hospitalized COVID-19 patients (COLVID-19 trial) and 227 patients were recruited. The primary outcome was the rate of critical disease in 30 days defined as need of mechanical ventilation, intensive care unit (ICU), or death.

RESULTS

152 non-anti-SARS-CoV-2-vaccinated patients (colchicine vs controls: 77vs75, mean age 69.1±13.1 vs 67.9±15 years, 39% vs 33.3% females, respectively) were analyzed. There was no difference in co-primary end-points between patients treated with colchicine compared to controls (mechanical ventilation 5.2% vs 4%, ICU 1.3% vs 5.3%, death 9.1% vs 6.7%, overall 11 (14.3%) vs 10 (13.3%) patients, P=ns, respectively). Mean time to discharge was similar (colchicine vs controls 14.1±10.4 vs 14.7±8.1 days). Older age (>60 years, P=0.025), P/F<275 mmHg (P=0.005), AST>40 U/L (P<0.001), pre-existent heart (P=0.02), lung (P=0.003), upper-gastrointestinal (P=0.014), lower-gastrointestinal diseases (P=0.009) and cancer (P=0.008) were predictive of achieving the primary outcome. Diarrhoea (9.1% vs 0%, p=0.0031) and increased levels of AST at 6 days (76.9±91.8 vs 33.5±20.7 U/l, P=0.016) were more frequent in the colchicine group.

CONCLUSION

Colchicine did not reduce the rate and the time to the critical stage. Colchicine was relatively safe although adverse hepatic effects require caution. We confirm that older (>60 years) patients with comorbidities are characterized by worse outcome.

Molecular Insights in Atrial Fibrillation Pathogenesis and Therapeutics: A Narrative Review

The prevalence of atrial fibrillation (AF) is bound to increase globally in the following years, affecting the quality of life of millions of people, increasing mortality and morbidity, and beleaguering health care systems. Increasingly effective therapeutic options against AF are the constantly evolving electroanatomic substrate mapping systems of the left atrium (LA) and ablation catheter technologies. Yet, a prerequisite for better long-term success rates is the understanding of AF pathogenesis and maintenance. LA electrical and anatomical remodeling remains in the epicenter of current research for novel diagnostic and treatment modalities. On a molecular level, electrical remodeling lies on impaired calcium handling, enhanced inwardly rectifying potassium currents, and gap junction perturbations. In addition, a wide array of profibrotic stimuli activates fibroblast to an increased extracellular matrix turnover via various intermediaries. Concomitant dysregulation of the autonomic nervous system and the humoral function of increased epicardial adipose tissue (EAT) are established mediators in the pathophysiology of AF. Local atrial lymphomononuclear cells infiltrate and increased inflammasome activity accelerate and perpetuate arrhythmia substrate. Finally, impaired intracellular protein metabolism, excessive oxidative stress, and mitochondrial dysfunction deplete atrial cardiomyocyte ATP and promote arrhythmogenesis. These overlapping cellular and molecular alterations hinder us from distinguishing the cause from the effect in AF pathogenesis. Yet, a plethora of therapeutic modalities target these molecular perturbations and hold promise in combating the AF burden. Namely, atrial selective ion channel inhibitors, AF gene therapy, anti-fibrotic agents, AF drug repurposing, immunomodulators, and indirect cardiac neuromodulation are discussed here.

Anti-inflammatory Therapies for Coronary Heart Disease: A Systematic Review and Meta-Analysis

Background: Anti-inflammatory therapy has been proposed as a promising treatment for coronary heart disease (CHD) that could reduce residual inflammation risk (RIR) and therefore major adverse cardiovascular events. We implemented a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the clinical benefits of anti-inflammatory agents in patients with CHD based on secondary cardiovascular prevention. Methods: We systemically searched the PubMed, Embase, and Cochrane Library databases for RCTs (published between Jan 1, 1950, and June 1, 2021; no language restrictions) that focused on anti-inflammatory therapy for coronary heart disease. Our primary end points of interest were a composite of all-cause death, recurrent myocardial infarction and stroke. We processed pooled data using a random-effects model. Results: Of 1497 selected studies, 18 studies with 67,449 participants met our inclusion criteria and were included in the present meta-analysis. Comparing anti-inflammatory agents with placebo, there was no significant decrease in risk of primary end points, secondary end points, all-cause mortality, cardiac mortality, recurrent myocardial infarction, stroke or revascularization. Further subgroup analysis indicated that anti-inflammatory agents led to a significant reduction in secondary end points (OR 0.87, CI 0.77-0.99; P = 0.03), recurrent myocardial infarction (OR 0.86, CI 0.78-0.95; P = 0.003) and revascularization (OR 0.81, CI 0.70-0.92; P = 0.001) in patients with stable CHD compared with placebo. Moreover, stable CHD patients had a lower propensity for recurrent myocardial infarction than acute coronary syndrome (ACS) patients when using anti-inflammatory agents (P = 0.03). The colchicine subgroup analysis showed that colchicine yielded a promising reduction in the primary end points (OR 0.81, CI 0.70-0.95; P = 0.009) compared with placebo. Anti-inflammatory agents were associated with a higher risk of infection (OR 1.13, CI 1.03-1.23; P = 0.007) and negligible effects on cancers (OR 0.98, CI 0.90-1.06; P = 0.61). Conclusion: Anti-inflammatory agents appear to have beneficial effects in reducing the risk of recurrent myocardial infarction in patients with stable CHD, albeit at the cost of increased infection. Notably, colchicine demonstrates a promising cardioprotective effect with a lower incidence of major cardiovascular events and thus is a potential therapeutic strategy for stable CHD patients. Systematic Review Registration: PROSPERO, identifier CRD42021245514.