Efficacy and safety of long-term treatment with intravenous colchicine for familial Mediterranean fever (FMF) refractory to oral colchicine.

Colchicine is the mainstay of treatment for familial Mediterranean fever (FMF). Intravenous (IV) colchicine, administered over several months, has been shown to be effective for FMF patients unresponsive to oral colchicine. The objective of this study was to evaluate the efficacy and safety of long-term IV colchicine treatment in oral colchicine-resistant FMF. We analyzed data of 15 patients with frequent FMF attacks, despite a maximal tolerated dose of oral colchicine (2-3 mg/day), who were treated with weekly IV injections of 1 mg of colchicine for at least 12 months. Treatment efficacy was determined by changes in frequency, duration and severity of FMF attacks. Safety was assessed according to adverse events. The mean duration of IV colchicine treatment was 5.16 ± 2.85 years. Decreases were observed from pre-treatment period in the monthly mean rates of abdominal attacks (from 5.6 ± 3.7 to 1.9 ± 3.3, p = 0.0009), joint attacks (from 6.5 ± 5.1 to 1.6 ± 1.6, p = 0.01) and overall attacks (from 22.3 ± 16.2 to 7.4 ± 5.7, p = 0.002) as well as in the mean duration (from 3.8 ± 1.5 to 2.4 ± 1.1 days per attack, p = 0.008) and severity of attacks (from 9.9 ± 0.3 to 5.7 ± 2.6, on a scale of 0-10, p < 0.05). The rate of adverse events was low, and they were mainly gastrointestinal. No severe or serious adverse events were recorded. Long-term treatment with IV colchicine in patients unresponsive to oral colchicine therapy is effective and safe.