General Information

Colcrys (colchicine) is a toxic natural product and secondary metabolite, originally extracted from plants of the genus Colchicum (Autumn crocus, Colchicum autumnale, also known as Meadow saffron). The exact mechanism of action by which Colcrys works is not fully known. However, evidence suggests that colchicine may interfere with the intracellular assembly of the inflammasome complex present in neutrophils and monocytes that mediates activation of interleukin-1ß. Additionally, colchicine prevents the activation, degranulation, and migration of neutrophils thought to mediate some gout symptoms.

Colcrys is specifically indicated for the prophylaxis of gout flares, the treatment of acute gout flares when taken at the first sign of a flare and the treatment of familial Mediterranean fever in adults and children four years of age and older.

Colcrys are supplied as tablets for oral administration. The recommended initial doses are as follows:
Prophylaxis of Gout Flares:
For adults and adolescents older than 16 years of age the recommended dose is 0.6 mg once or twice daily. The maximum recommended dose for prophylaxis of gout flares is 1.2 mg/day.
Treatment of Gout Flares:
1.2 mg (2 tablets) at the first sign of the flare followed by 0.6 mg (1 tablet) one hour later. The maximum recommended dose for treatment of gout flares is 1.8 mg over a 1 hour period. Colcrys may be administered for treatment of a gout flare during prophylaxis at doses not to exceed 1.2 mg (2 tablets) at the first sign of the flare followed by 0.6 mg (1 tablet) one hour later. Wait 12 hours and then resume the prophylactic dose.
Familial Mediterranean Fever
The recommended dose in adults is 1.2 mg to 2.4 mg daily. The dose should be increased as needed to control disease and as tolerated in increments of 0.3 mg/day to a maximum recommended daily dose.
Recommended Pediatric Dosage
Prophylaxis and Treatment of Gout Flares:
Colcrys is not recommended for pediatric use for this indication.
Familial Mediterranean Fever
The recommended dosage in pediatric patients 4 years of age and older is based on age. The following daily doses may be given as a single or divided dose twice daily:
Children 4 - 6 years: 0.3 mg to 1.8 mg daily
Children 6 - 12 years: 0.9 mg to 1.8 mg daily
Adolescents older than 12 years: 1.2 mg to 2.4 mg daily

Clinical Results

FDA Approval
The FDA approval of Colcrys for gout was based on two randomized clinical trials. These trials assessed the efficacy of colchicine 0.6 mg twice a day for the prophylaxis of gout flares in patients with gout initiating treatment with urate lowering therapy. In both trials treatment with colchicine decreased the frequency of gout flares. Specific results from one of the trials are as follows:
This was a multicenter, randomized, double-blind, placebo-controlled, parallel group, 1 week, dose comparison study. The subjects were randomly assigned to three groups: (1) high-dose colchicine (1.2 mg, then 0.6 mg hourly × 6 hours [4.8 mg total]); (2) low-dose colchicine (1.2 mg, then 0.6 mg in 1 hour [1.8 mg total] followed by 5 placebo doses hourly); or (3) placebo (2 capsules, then 1 capsule hourly × 6 hours). Subjects took the first dose within 12 hours of the onset of the flare and recorded pain intensity (11-point Likert scale) and adverse events over 72 hours. Efficacy was measured based on response to treatment in the target joint, using patient self assessment of pain at 24 hours following the time of first dose as recorded in the diary. A responder was one who achieved at least a 50% reduction in pain score at the 24-hour post-dose assessment relative to the pre-treatment score and did not use rescue medication prior to the actual time of 24-hour post-dose assessment. Rates of response were similar for the low-dose treatment group (38%) and the high-dose group (33%) but were higher as compared to the placebo group (16%).

The FDA approval of Colcrys for familial Mediterranean fever (FMF) was based on three randomized, placebo-controlled studies.
Study One
This 6-month crossover study randomized 15 subjects with FMF, 5 of whom discontinued due to study non-compliance. The 10 subjects who completed the study experienced 5 attacks over the course of 90 days while treated with colchicine compared to 59 attacks over the course of 90 days while treated with placebo.
Study Two
This 4-month crossover study randomized 22 subjects with FMF, 9 of whom discontinued due to lack of efficacy while receiving placebo or study non-compliance. The 13 subjects who completed the study experienced 18 attacks over the course of 60 days while treated with colchicine compared to 68 attacks over the course of 60 days while treated with placebo.
Study Three
This study was discontinued after an interim analysis of 6 of the 11 subjects enrolled had completed the study; results could not be confirmed.

Mechanism of Action