Colchicine dose reduction in patients with normal liver and kidney function: comment on the article by Terkeltaub et al

Consensus Statement Regarding the Efficacy and Safety of Long-Term Low-Dose Colchicine in Gout and Cardiovascular Disease

Over the last decade, evidence has demonstrated that long-term, low-dose colchicine (0.5 mg daily) is effective for preventing gout flare and cardiovascular (CV) events in a wide range of patients. Given the potentially expanding use of colchicine in CV disease, we here review and update the biologic effects and safety of colchicine based on recent data gathered from bench and pharmacodynamic studies, clinical reports, controlled clinical trials, and meta-analyses, integrated with important studies over the last 50 years, to offer a consensus perspective by experts from multiple specialties familiar with colchicine's long-term use. We conclude that the clinical benefits of colchicine in gout and CV disease achieved at low dose do not sustain serum levels above the upper limit of safety when used in patients without advanced renal or liver disease or when used concomitantly with most medications. Further, data accrued over the last 50 years strongly suggest that the biologic effects of long-term colchicine do not increase the risk of cancer, sepsis, cytopenia, or myotoxicity.

Colchicine and the heart

Colchicine is a unique, sophisticated anti-inflammatory agent that has been used for decades for the prevention of acute inflammatory flares in gout and familial Mediterranean fever. In recent years, clinical trials have demonstrated its potential in a range of cardiovascular (CV) conditions. Colchicine is avidly taken up by leucocytes, and its ability to bind to tubulin and interfere with microtubular function affects the expression of cytokines and interleukins, and the ability of neutrophils to marginate, ingress, aggregate, express superoxide, release neutrophil extracellular traps, and interact with platelets. In patients with acute and recurrent pericarditis, clinical trials in >1600 patients have consistently shown that colchicine halves the risk of recurrence [relative risk (RR) 0.50, 95% confidence interval (CI) 0.42–0.60]. In patients with acute and chronic coronary syndromes, multicentre randomized controlled trials in >11 000 patients followed for up to 5 years demonstrated that colchicine may reduce the risk of CV death, myocardial infarction, ischaemic stroke and ischaemia-driven revascularization by >30% (RR 0.63, 95% CI 0.49–0.81). The use of colchicine at doses of 0.5–1.0 mg daily in CV trials has proved safe. Early gastrointestinal intolerance limits its use in ∼10% of patients; however, ∼90% of patients tolerate it well over the long term. Despite isolated case reports, clinically relevant drug interactions with moderate to strong CYP3A4 inhibitors/competitors or P-glycoprotein inhibitors/competitors are rare if this dosage of colchicine is used in the absence of advanced renal or liver disease. The aim of this review is to summarize the contemporary data supporting the efficacy and safety of colchicine in patients with CV disease.

Fab fragments of ovine antibody to colchicine enhance its clearance in the rat

CONTEXT

Colchicine is an anti-inflammatory alkaloid used for the treatment of acute gout, but has a narrow therapeutic index. Colchicine overdoses are relatively rare, but have high mortality requiring rapid treatment.

OBJECTIVE

To evaluate the ability of a newly available ovine fragment antigen-binding (Fab) antibody to colchicine (ColchiFab(™)) to protect rats against renal and other injury 24 h after colchicine ingestion.

MATERIALS AND METHODS

Rats were gavaged with colchicine (5 mg/kg), then 2 h later injected intraperitoneally with 5 ml of sterile saline, or Fab anti-colchicine, a newly available ovine antibody to colchicine. Samples of blood were taken at 1, 2, 5 and 24 h after gavage, and urine was collected from 5 to 24 h after gavage. Concentrations of colchicine in tissue, blood and urine were measured by liquid chromatography/mass spectrometry, concentrations of Fab anti-colchicine, urinary neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 or KIM-1 by enzyme-linked immunosorbent assay or ELISA, while concentrations of creatine kinase and creatinine (Cr) were measured enzymatically.

RESULTS

Colchicine equilibrated rapidly throughout the body and increased serum creatine kinase. Fab anti-colchicine also rapidly redistributed to the blood and remained at high concentrations over 24 h. Fab anti-colchicine caused a rapid 7.1-fold increase in serum colchicine level, followed by excretion of both colchicine and Fab anti-colchicine through the urine. This was associated with the accumulation of colchicine in the kidney, a reversal of colchicine-induced diarrhoea, and increasing urinary NGAL level; from 168 ± 48 to 477 ± 255 ng/mmol Cr [mean ± standard deviation or SD].

DISCUSSION

Fab anti-colchicine greatly increased the clearance of colchicine, although increasing NGAL level suggested the presence of mild kidney damage.

CONCLUSION

These data suggest clinical utility for Fab anti-colchicine in the treatment of colchicine overdose.