Teaching an Old Dog New Tricks: Colchicine in Cardiovascular Medicine

Colchicine for the primary prevention of cardiovascular events

BACKGROUND

Atherosclerotic cardiovascular diseases (ACVDs), a condition characterised by lipid accumulation in arterial walls, which is often exacerbated by chronic inflammation disorders, is the major cause of mortality and morbidity worldwide. Colchicine, with its first medicinal use in ancient Egypt, is an inexpensive drug with anti-inflammatory properties. However, its role in primary prevention of ACVDs in the general population remains unknown.

OBJECTIVES

To assess the clinical benefits and harms of colchicine as primary prevention of cardiovascular outcomes in the general population.

SEARCH METHODS

We searched the Cochrane Heart Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase, Web of Science, and LILACS. We searched ClinicalTrials.gov and WHO ICTRP for ongoing and unpublished studies. We also scanned the reference lists of relevant included studies, reviews, meta-analyses, and health technology reports to identify additional studies. There were no limitations on language, date of publication, or study setting. The search results were updated on 31 May 2023.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in any setting, recruiting adults without pre-existing cardiovascular disease. We included trials that compared colchicine versus placebo, non-steroidal anti-inflammatory drugs, corticosteroids, immunomodulating drugs, or usual care. Our primary outcomes were all-cause mortality, non-fatal myocardial infarction, stroke, and adverse events.

DATA COLLECTION AND ANALYSIS

Two or more review authors independently selected studies, extracted data, and performed risk of bias and GRADE assessments.

MAIN RESULTS

We identified 15 RCTs (1721 participants randomised; 1412 participants analysed) with follow-up periods ranging from 4 to 728 weeks. The intervention was oral colchicine compared with placebo, immunomodulating drugs, or usual care or no treatment. Due to biases and imprecision, the evidence was very uncertain for all outcomes. All trials but one had a high risk of bias. Five out of seven meta-analyses included fewer than six trials (71.4%). The objectives of the review were to assess cardiovascular outcomes in the general population, but many of the included trials focused on liver disease. Colchicine compared to placebo Colchicine may reduce all-cause mortality compared to placebo in primary prevention, but the evidence is very uncertain (risk ratio (RR) 0.68, 95% confidence interval (CI) 0.51 to 0.91; 6 studies, 463 participants; very low-certainty evidence; number needed to treat for an additional beneficial outcome (NNTB) 11, 95% CI 6 to 67). Colchicine may result in little to no difference in non-fatal myocardial infarction, but the evidence is very uncertain (RR 0.87, 95% CI 0.41 to 1.82; 1 study, 100 participants; very low-certainty evidence). Colchicine may not reduce the incidence of stroke, but the evidence is very uncertain (RR 2.43, 95% CI 0.67 to 8.86; 1 study, 100 participants; very low-certainty evidence). Regarding adverse events, colchicine may increase the incidence of diarrhoea (RR 3.99, 95% CI 1.44 to 11.06; 8 studies, 605 participants; very low-certainty evidence; number needed to treat for an additional harmful outcome (NNTH) 10, 95% CI 6 to 17), and may have little to no effect on neurological outcomes such as seizure or mental confusion (RR 0.72, 95% CI 0.31 to 1.66; 2 studies, 155 participants; very low-certainty evidence), but the evidence is very uncertain. The effect of colchicine on cardiovascular mortality is also very uncertain (RR 1.27, 95% CI 0.03 to 62.43; 2 studies, 160 participants; very low-certainty evidence). Colchicine may not reduce post-cardiac procedure atrial fibrillation, but the evidence is very uncertain (RR 0.74, 95% CI 0.25 to 2.19; 1 study, 100 participants). We found no trials reporting on pericardial effusion, peripheral artery disease, heart failure, or unstable angina. Colchicine compared to methotrexate (immunomodulating drug) Colchicine may result in little to no difference in all-cause mortality compared to methotrexate, but the evidence is very uncertain (RR 0.42, 95% CI 0.12 to 1.51; 1 study, 85 participants; very low-certainty evidence). We found no trials reporting other cardiovascular outcomes or adverse events for this comparison. Colchicine compared to usual care or no treatment The evidence is very uncertain about the effect of colchicine compared with usual care on all-cause mortality in primary prevention (RR 1.07, 95% CI 0.90 to 1.27; 2 studies, 729 participants; very low-certainty evidence). Regarding adverse events, colchicine may increase the incidence of diarrhoea compared to usual care, but the evidence is very uncertain (RR 3.32, 95% CI 1.56 to 7.03; 2 studies, 729 participants; very low-certainty evidence; NNTH 18, 95% CI 12 to 42). No trials reported other cardiovascular outcomes for this comparison.

AUTHORS' CONCLUSIONS

This Cochrane review evaluated the clinical benefits and harms of using colchicine for the primary prevention of cardiovascular events in the general population. Comparisons were made against placebo, immunomodulating medications, or usual care or no treatment. However, the certainty of the evidence for the predefined outcomes was very low, highlighting the pressing need for high-quality, rigorous studies to ascertain colchicine's clinical impact definitively. We identified numerous biases and inaccuracies in the included studies, limiting their generalisability and precluding a conclusive determination of colchicine's efficacy in preventing cardiovascular events. The existing evidence regarding colchicine's potential cardiovascular benefits or harms for primary prevention is inconclusive owing to the limitations inherent in the current studies. More robust clinical trials are needed to bridge this evidence gap effectively.

A survey on Shar Pei autoinflammatory disease in the United Kingdom

OBJECTIVES

To characterise the fever episodes attributed to Shar Pei autoinflammatory disease and to identify common diagnostic and management strategies in the United Kingdom. A secondary objective was to determine risk factors associated with Shar Pei autoinflammatory disease fever episodes.

METHODS

A retrospective survey was performed to characterise episodes of Shar Pei autoinflammatory disease fever and to identify commonly used treatments in affected dogs. Clinical data were collected from owners and veterinarians. Frequencies of previously proposed risk factors (skin thickness and folding, muzzle conformation) and comorbid conditions were compared between dogs that had exhibited fever episodes consistent with Shar Pei autoinflammatory disease and those who had not.

RESULTS

At least one episode of fever attributed to Shar Pei autoinflammatory disease was reported in 52 of 106 (49%) Shar Pei. Nine other dogs had fever episodes consistent with Shar Pei autoinflammatory disease reported by their owners but not by veterinarians. Median rectal temperature at presentation for Shar Pei autoinflammatory disease fever was 40.1°C [104.2°F] (39.9 to 41.3°C [103.8 to 106.3°F]) and owners reported associated hyporexia (n=33, 63%) and vomiting (n=8, 15%) more frequently than veterinary records (n=22, 42% and n=0, 0%, respectively). The median number of veterinary appointments for Shar Pei autoinflammatory disease was two per dog (1 to 15) while owners reported a median of four episodes per dog per year. None of the assessed phenotypic variants or comorbidities were significantly associated with exhibiting Shar Pei autoinflammatory disease fever episodes.

CLINICAL SIGNIFICANCE

Episodes of Shar Pei autoinflammatory disease fever were reported approximately twice as frequently by owners compared to veterinary records, suggesting the burden of this condition may be underestimated by veterinarians. Specific risk factors for Shar Pei autoinflammatory disease fever were not identified.

Evolving Diagnostic and Management Advances in Coronary Heart Disease

Despite considerable improvement in diagnostic modalities and therapeutic options over the last few decades, the global burden of ischemic heart disease is steadily rising, remaining a major cause of death worldwide. Thus, new strategies are needed to lessen cardiovascular events. Researchers in different areas such as biotechnology and tissue engineering have developed novel therapeutic strategies such as stem cells, nanotechnology, and robotic surgery, among others (3D printing and drugs). In addition, advances in bioengineering have led to the emergence of new diagnostic and prognostic techniques, such as quantitative flow ratio (QFR), and biomarkers for atherosclerosis. In this review, we explore novel diagnostic invasive and noninvasive modalities that allow a more detailed characterization of coronary disease. We delve into new technological revascularization procedures and pharmacological agents that target several residual cardiovascular risks, including inflammatory, thrombotic, and metabolic pathways.

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.

The interconnections between the microtubules and mitochondrial networks in cardiocerebrovascular diseases: Implications for therapy

Microtubules, a highly dynamic cytoskeleton, participate in many cellular activities including mechanical support, organelles interactions, and intracellular trafficking. Microtubule organization can be regulated by modification of tubulin subunits, microtubule-associated proteins (MAPs) or agents modulating microtubule assembly. Increasing studies demonstrate that microtubule disorganization correlates with various cardiocerebrovascular diseases including heart failure and ischemic stroke. Microtubules also mediate intracellular transport as well as intercellular transfer of mitochondria, a power house in cells which produce ATP for various physiological activities such as cardiac mechanical function. It is known to all that both microtubules and mitochondria participate in the progression of cancer and Parkinson's disease. However, the interconnections between the microtubules and mitochondrial networks in cardiocerebrovascular diseases remain unclear. In this paper, we will focus on the roles of microtubules in cardiocerebrovascular diseases, and discuss the interplay of mitochondria and microtubules in disease development and treatment. Elucidation of these issues might provide significant diagnostic value as well as potential targets for cardiocerebrovascular diseases.

Colchicine for Patients With Coronary Artery Disease: A Systematic Review and Meta-analysis

Several randomized controlled trials have studied the role of colchicine, a potent anti-inflammatory drug, to prevent adverse cardiovascular events in patients with coronary artery disease (CAD). In this meta-analysis, we aimed to determine the role of colchicine in patients with CAD in clinical outcomes and mortality. We searched PubMed, PubMed Central, Scopus, and Embase for randomized controlled trials/experimental studies evaluating the role of colchicine in patients with CAD. After assessing the eligibility for inclusion, risk-of-bias assessment, and data extraction from the included studies, a narrative synthesis was conducted. Of 17 studies included for the qualitative analysis, 11 studies reported that inflammatory markers such as C-reactive protein and cytokines were reduced in the colchicine group, suggesting an anti-inflammatory role of colchicine in CAD. Quantitative analysis with pooling of data from 9 studies using a fixed-effect model showed 28% lower odds of acute myocardial infarction [odds ratio (OR) 0.72, 95% CI 0.59-0.86; n = 11,712], 52% lower occurrence of stroke (OR 0.48, 95% CI 0.30-0.76), and 37% reduction in odds of coronary revascularization procedure in the colchicine group (OR 0.63, 95% CI 0.52-0.76; n= 11,258). However, the odds of gastrointestinal adverse events were 50% higher in the colchicine group (OR 1.50, 95% CI 1.01-2.23; n = 12,214). In conclusion, colchicine is associated with a lower risk of acute myocardial infarction, stroke, and coronary revascularization. However, there is some increased risk of gastrointestinal adverse events with the use of colchicine.

Colchicine may become a new cornerstone therapy for coronary artery disease: a meta-analysis of randomized controlled trials

PURPOSE

Colchicine is an ancient anti-inflammatory drug. In recent years, an increasing number of studies have shown that colchicine improves the prognosis of patients with coronary artery disease (CAD), while other studies have reported the opposite. The aim of this study was to evaluate the relative efficacy and safety of colchicine in treating CAD.

METHODS

PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov were searched from inception to 20 October 2020 for randomized controlled trials (RCTs) comparing colchicine and placebo in patients with CAD. The primary outcomes were the primary composite outcomes of cardiovascular death, myocardial infarction (MI), ischemic stroke, or ischemia-driven coronary revascularization after colchicine administration. The secondary outcomes were cardiovascular death, death from any cause, noncardiac death, MI, ischemic stroke, coronary revascularization, gastrointestinal (GI) symptoms, and the different effects of colchicine in acute and chronic CAD. We assessed the pooled odds ratio (OR) of all-cause and cardiovascular mortality for CAD in fixed-effects models, the pooled risk ratio (RR) of the primary composite outcomes, MI, ischemic stroke, and ischemia-driven coronary revascularization in fixed-effects models and the pooled RR of GI symptoms in random-effects models. The Cochrane risk of bias tool was used to assess the risk of bias in the included RCTs.

FINDINGS

Eleven of the 894 identified studies (n = 12,899 patients) were included (6501 subjects in the colchicine group; 6389 subjects in the control group). The colchicine group had significantly lower pooled RRs of the primary composite outcomes (0.73, 95% confidence interval (CI) 0.64-0.84, P < 0.0001), MI (0.77, 95% CI 0.64-0.92, P = 0.004), ischemic stroke (0.47, 95% CI 0.30-0.76, P = 0.002), and ischemia-driven coronary revascularization (0.77, 95% CI 0.66-0.89, P = 0.0007), while the pooled RR of adverse GI events (2.15 95% CI 1.40-3.31, P = 0.0005) was significantly higher. Colchicine had a lower pooled RR of ischemic stroke (0.28, 95% CI 0.12-0.65, P = 0.003) for patients with acute compared with chronic CAD.

IMPLICATIONS

Colchicine treatment significantly decreased the risk of primary cardiovascular composite outcomes, MI, ischemic stroke, and ischemia-driven coronary revascularization in CAD patients but increased adverse GI events. There was no significant difference in all-cause mortality, cardiovascular mortality, and non-cardiovascular death between the colchicine and control groups. Colchicine performs better in acute CAD patients with ischemic stroke than chronic CAD patients. Colchicine might be a new treatment for patients with CAD.

Repurposing Colchicine for Heart Disease

Colchicine is one of the most ancient medications still prescribed. It is extracted from the Colchicum autumnale plant and is routinely used because of its broad anti-inflammatory properties to treat gout and familial Mediterranean fever. Colchicine has shown efficacy in various clinical settings in which inflammation is a key component, and it has become first-line therapy for acute and recurrent pericarditis. Two landmark clinical trials have recently shown that colchicine significantly improves cardiovascular outcomes on background statin and antiplatelet therapy in patients with coronary artery disease, supporting its role for the prevention of atherothrombotic events. Favorable results have also emerged in atrial fibrillation. We herein briefly review the most recent data related to the multiple cardiovascular conditions for which colchicine has been successfully repurposed. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 62 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Psoriasis and Cardiovascular Disease: A Narrative Review

Psoriasis is a chronic, autoimmune, and inflammatory disease that affects 2% of the world's population. In recent years, it has been demonstrated that psoriasis confers a 25% increase in relative risk of cardiovascular disease, independent of factors such as hyperlipidemia, smoking, and obesity. The objective of this review was to analyze and describe the association between psoriasis and cardiovascular disease. In this review, we describe the epidemiological association of psoriasis and cardiovascular disease, pathophysiology, mechanisms, and its association with the well-known cardiovascular risk calculators. In addition, we describe diagnostic tools, such as imaging techniques and novel biomarkers, that are useful in the evaluation of atherosclerotic cardiovascular disease. Finally, we present different systemic therapies that are used in patients with psoriasis and their effect on atherosclerotic cardiovascular disease. This article provides an overview of the current literature on psoriasis and cardiovascular risk, which can be useful for primary care physicians in their daily clinical practice.

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

Colchicine's medical evolution is historically bound to the Mediterranean basin, since remarkable researchers from this region underscored its valuable properties. With the passing of years colchicine became an essential pharmaceutical substance for the treatment of rheumatologic and cardiovascular diseases. In light of recent findings, the therapeutic value of colchicine has grown. In clinical practice, colchicine remains underutilized in view of its proven efficacy and safety. Its complex pharmacokinetics and multifaceted anti-inflammatory role remain under investigation. The current review addresses the safe administration of colchicine in view of key drug to drug interactions. Finally, we are briefly presenting colchicine's future potential applications.

Colchicine inhibits the prothrombotic effects of oxLDL in human endothelial cells

BACKGROUND

Tissue Factor (TF) plays a pivotal role in coronary thrombosis. Oxidized low-density lipoproteins (oxLDL) are crucial in development of atherosclerosclerosis. Moreover, oxLDL are known to induce TF expression on several cell types including endothelial cells. The lectin-type oxidized LDL receptor 1 (LOX-1) represent the oxLDL receptor. Colchicine is an anti-mitotic drug recently proven to have beneficial effects in cardiovascular disease via unknown mechanisms. Thus, we aim at investigating colchicine effects on TF expression in oxLDL stimulated human vascular endothelial cells (HUVEC). Some molecular mechanism(s) potentially involved were investigated.

METHODS

HUVEC were pre-incubated with colchicine 10 μM for 1 h and then stimulated with oxLDL (50 μg/mL). TF gene (RT-PCR), protein (western blot), surface expression (FACS) and procoagulant activity (FXa generation assay) were measured. TF translocation to cell surface was investigated by immunofluorescence. NF-κB/IκB axis was examined by western blot analysis and translocation assay. Finally, LOX-1 expression was also investigated.

RESULTS

Colchicine significantly reduced TF gene and protein expression as well as its procoagulant activity in oxLDL-treated HUVEC. These effects seem to be related mainly to action of colchicine on microtubules that, in turn, modulate TF trafficking in the cytoplasm, NF-κB/IκB pathway and LOX-1 expression.

CONCLUSIONS

Data of the present study, although in vitro, indicate that one of the hypothetical mechanisms by which colchicine exert protective cardiovascular effects might be its ability to inhibit the pro-thrombotic activity of oxLDL.

Adverse events of colchicine for cardiovascular diseases: a comprehensive meta-analysis of 14 188 patients from 21 randomized controlled trials

AIMS

Colchicine has an emerging role in the cardiovascular field, although, concerns for side effects, especially gastrointestinal, limit its prescription. We aimed at evaluating reported side effects of colchicine for cardiovascular indications.

METHODS

We performed a meta-analysis of published randomized controlled trials on colchicine for the treatment of cardiovascular diseases. Random-effects meta-analysis was used to assess the risk of adverse events and drug withdrawal. Publication bias was assessed using the Egger test, and meta-regression was performed to assess sources of heterogeneity.

RESULTS

Among 14 188 patients, 7136 patients received colchicine while the other 7052 received placebo. The occurrence of any adverse event with colchicine was reported in 15.3 vs. 13.9% patients [relative risk (RR) 1.26, 95% confidence interval (CI) 0.96-1.64, P = 0.09]. Gastrointestinal events were reported in 16.1 vs. 12.2% (RR 2.16, 95% CI 1.50-3.12, P < 0.001), while diarrhea was reported in 12.5 vs. 8.1% (RR 2.77, 95% CI 1.55-4.94, P < 0.001). The risk of gastrointestinal events increased with daily dose and shorter treatment duration. Myalgias were observed in 21 vs. 18% patients (RR 1.16, 95% CI 1.02-1.32, P = 0.03). Other adverse events such as myotoxicity, hepatic adverse events, hematologic adverse events, cutaneous adverse events, infection or death were not increased by colchicine treatment. Colchicine discontinuation was reported in 4.8 vs. 3.4% patients (RR 1.54, 95% CI 1.20-1.99, P < 0.001).

CONCLUSION

Colchicine is associated with increased risk of gastrointestinal events and myalgias, but not of other adverse events. The risk of gastrointestinal events may be avoided with lower dose (0.5 mg/daily) and is inversely related to treatment duration, possibly due to early drug discontinuation or drug tolerance.

Colchicine for acute and chronic coronary syndromes

Colchicine is an ancient drug, traditionally used for the treatment and prevention of gouty attacks; it has become standard of treatment for pericarditis with a potential role in the treatment of coronary artery disease. Atherosclerotic plaque formation, progression, destabilisation and rupture are influenced by active proinflammatory cytokines interleukin (IL)-1β and IL-18 that are generated in the active forms by inflammasomes, which are cytosolic multiprotein oligomers of the innate immune system responsible for the activation of inflammatory responses. Colchicine has a unique anti-inflammatory mechanism: it is not only able to concentrate in leucocytes, especially neutrophils, and block tubulin polymerisation, affecting the microtubules assembly, but also inhibits (NOD)-like receptor protein 3 (NLRP3) inflammasome. On this basis, colchicine interferes with several functions of leucocytes and the assembly and activation of the inflammasome as well, reducing the production of interleukin 1β and interleukin 18. Long-term use of colchicine has been associated with a reduced rate of cardiovascular events both in chronic and acute coronary syndromes, with an overall good safety profile. This review will focus on the influence of colchicine on the pathophysiology of coronary artery disease, reviewing essential pharmacology and discussing the most important and recent clinical studies. On the basis of current literature, colchicine is emerging as a possible new valuable, safe and cheap agent for the treatment of acute and chronic coronary syndromes.

Colchicine in Pericardial Disease: from the Underlying Biology and Clinical Benefits to the Drug-Drug Interactions in Cardiovascular Medicine

PURPOSE OF REVIEW

This is an in-depth review on the mechanism of action, clinical utility, and drug-drug interactions of colchicine in the management of pericardial disease.

RECENT FINDINGS

Recent evidence about therapeutic targets on pericarditis has demonstrated that NALP3 inflammasome blockade is the cornerstone in the clinical benefits of colchicine. Such benefits extend from acute and recurrent pericarditis to transient constriction and post-pericardiotomy syndrome. Despite the increased utilization of colchicine in cardiovascular medicine, safety concerns remains unsolved regarding the long-term use of colchicine in the cardiac patient. Moreover, recent evidence has demonstrated that numerous cardiovascular medications, ranging from antihypertensive medication to antiarrhythmics, are known to interact with the CYP3A4 and/or P-gp system increasing the toxicity potential of colchicine. The use of adjunctive colchicine in the management of inflammatory pericardial diseases is standard of care in current practice. It is advised that a careful medication reconciliation with emphasis on pharmacokinetic is completed before prescribing colchicine in order to avoid harmful interaction by finding an alternative regimen or adjusting colchicine dosing.

Cardioprotective Role of Colchicine Against Inflammatory Injury in a Rat Model of Acute Myocardial Infarction

BACKGROUND

Inflammation plays a crucial role in the pathophysiology of myocardial ischemia/reperfusion (I/R) injury. A clinical trial has recently reported a smaller infarct size in a cohort of patients with ST-segment elevation myocardial infarction (MI) treated with a short colchicine course. The mechanism underlying colchicine-induced cardioprotection in the early MI phase remains unclear. We hypothesized that a short pretreatment with colchicine could induce acute beneficial effects by protecting the heart against inflammation in myocardial I/R injury.

METHODS AND RESULTS

Rats were subjected to 40-minute left anterior descending coronary occlusion, followed by 120-minute reperfusion. Colchicine (0.3 mg/kg) or a vehicle was administered per os 24 hours and immediately before surgery. Infarct size was significantly reduced in the colchicine group (35.6% ± 3.0% vs 46.6% ± 3.3%, P < .05). The beneficial effects of colchicine were associated with an increased systemic interleukin-10 (IL-10) level and decreased cardiac transforming growth factor-β level. Interleukin-1β was found to increase in a "time of reperfusion"-dependent manner. Colchicine inhibited messenger RNA expression of caspase-1 and pro-IL-18. Interleukin-1β injected 10 minutes prior to myocardial ischemia induced greater infarct size (58.0% ± 2.0%, P < .05) as compared to the vehicle. Colchicine combined to IL-1β injection significantly decreased infarct size (47.1% ± 2.2%, P < .05) as compared to IL-1β alone, while colchicine alone exhibited a significantly more marked cardioprotective effect than the colchicine-IL-1β association.

CONCLUSION

The cardioprotection induced by a short colchicine pretreatment was associated with an anti-inflammatory effect in the early reperfusion phase in our rat MI model.

Anti-colchicine Fab fragments prevent lethal colchicine toxicity in a porcine model: a pharmacokinetic and clinical study

Background: Colchicine poisoning is commonly lethal. Colchicine-specific Fab fragments increase rat urinary colchicine clearance and have been associated with a good outcome in one patient. We aimed to develop a porcine model of colchicine toxicity to study the pharmacokinetics and efficacy of ovine Fab.

Methods: A Göttingen minipig critical care model was established and serial blood samples taken for colchicine and Fab pharmacokinetics, clinical chemistry, and haematology. Animals were euthanised when the mean arterial pressure fell below 45 mmHg without response to vasopressor, or at study completion.

Results: Initial studies indicated that oral dosing produced variable pharmacokinetics and time-to-euthanasia. By contrast, intravenous infusion of 0.25 mg/kg colchicine over 1 h produced reproducible pharmacokinetics (AUC_0–20 343 [SD = 21] µg/L/h), acute multi-organ injury, and cardiotoxicity requiring euthanasia a mean of 22.5 (SD = 3.2) h after dosing. A full-neutralising equimolar Fab dose given 6 h after the infusion (50% first hour, 50% next 6 h [to reduce renal-loss of unbound Fab]) produced a 7.35-fold increase in plasma colchicine (AUC_0–20 2,522 [SD = 14] µg/L/h), and removed all free plasma colchicine, but did not prevent toxicity (euthanasia at 29.1 [SD = 3.4] h). Earlier administration over 1 h of the full-neutralising dose, 1 or 3 h after the colchicine, produced a 12.9-fold (AUC_0–20 4,433 [SD = 607] µg/L/h) and 6.0-fold (AUC_0–20 2,047 [SD = 51] µg/L/h) increase in plasma colchicine, respectively, absence of free plasma colchicine until 20 h, and survival to study end without marked cardiotoxicity.

Conclusions: Colchicine-specific Fab given early, in equimolar dose, bound colchicine, eliciting its movement into the blood, and preventing severe toxicity. Clinical studies are now needed to determine how soon this antidote must be given to work in human poisoning.