The recommended dosage of COLCRYS for prophylaxis of gout flares for adults and adolescents older than 16 years of age is 0.6 mg once or twice daily. The maximum recommended dose for prophylaxis of gout flares is 1.2 mg/day.
The recommended dose of COLCRYS for treatment of a gout flare is 1.2 mg (2 tablets) at the first sign of the flare followed by 0.6 mg (1 tablet) one hour later. Higher doses have not been found to be more effective. 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.
COLCRYS is not recommended for pediatric use in prophylaxis or treatment of gout flares.
The recommended dosage of COLCRYS for FMF 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
Concomitant Therapy:
Co-administration of COLCRYS with drugs known to inhibit CYP3A4 and/or P-glycoprotein (P-gp) increases the risk of colchicine-induced toxic effects (Table 1). If patients are taking or have recently completed treatment with drugs listed in Table 1 within the prior 14 days, the dose adjustments are as shown on the table below [see DRUG INTERACTIONS (7)].
Table 1 COLCRYS Dose Adjustment for Co-administration with Interacting Drugs if no Alternative AvailableFor magnitude of effect on colchicine plasma concentrations [see Pharmacokinetics (12.3)]
| Strong CYP3A4 Inhibitors Patients with renal or hepatic impairment should not be given COLCRYS in conjunction with strong CYP3A4 or P-gp inhibitors [see CONTRAINDICATIONS (4)]. |
|---|
| Drug | Noted or Anticipated Outcome | Gout Flares | FMF |
| | Prophylaxis of Gout Flares | Treatment of Gout Flares |
| | Original Intended Dosage | Adjusted Dose | Original Intended Dosage | Adjusted Dose | Original Intended Dosage | Adjusted Dose |
Atazanavir Clarithromycin Darunavir/ RitonavirWhen used in combination with Ritonavir, see dosing recommendations for strong CYP3A4 inhibitors [see CONTRAINDICATIONS (4)]. Indinavir Itraconazole Ketoconazole Lopinavir/ Ritonavir Nefazodone Nelfinavir Ritonavir Saquinavir Telithromycin Tipranavir/ Ritonavir | Significant increase in colchicine plasma levels; fatal colchicine toxicity has been reported with clarithromycin, a strong CYP3A4 inhibitor. Similarly, significant increase in colchicine plasma levels is anticipated with other strong CYP3A4 inhibitors. | 0.6 mg twice a day
0.6 mg once a day
| 0.3 mg once a day
0.3 mg once every other day | 1.2 mg (2 tablets) followed by 0.6 mg (1 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 1.2 – 2.4 mg | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
| Moderate CYP3A4 Inhibitors |
| Drug | Noted or Anticipated Outcome | Gout Flares | FMF |
| | Prophylaxis of Gout Flares | Treatment of Gout Flares |
| | Original Intended Dosage | Adjusted Dose | Original Intended Dosage | Adjusted Dose | Original Intended Dosage | Adjusted Dose |
Amprenavir Aprepitant Diltiazem Erythromycin Fluconazole Fosamprenavir (pro-drug of Amprenavir) Grapefruit Juice Verapamil | Significant increase in colchicine plasma concentration is anticipated. Neuromuscular toxicity has been reported with diltiazem and verapamil interactions. | 0.6 mg twice a day
0.6 mg once a day
| 0.3 mg twice a day or 0.6 mg once a day
0.3 mg once a day
| 1.2 mg (2 tablets) followed by 0.6 mg (1 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | 1.2 mg (2 tablets) × 1 dose. Dose to be repeated no earlier than 3 days.
| Maximum daily dose of 1.2 – 2.4 mg. | Maximum daily dose of 1.2 mg (may be given as 0.6 mg twice a day) |
| P-gp Inhibitors |
| Drug | Noted or Anticipated Outcome | Gout Flares | FMF |
| | Prophylaxis of Gout Flares | Treatment of Gout Flares |
| | Original Intended Dosage | Adjusted Dose | Original Intended Dosage | Adjusted Dose | Original Intended Dosage | Adjusted Dose |
| Cyclosporine Ranolazine | Significant increase in colchicine plasma levels; fatal colchicine toxicity has been reported with cyclosporine, a P-gp inhibitor. Similarly, significant increase in colchicine plasma levels is anticipated with other P-gp inhibitors. | 0.6 mg twice a day
0.6 mg once a day
| 0.3 mg once a day
0.3 mg once every other day | 1.2 mg (2 tablets) followed by 0.6 mg (1 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | 0.6 mg (1 tablet) × 1 dose. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 1.2 – 2.4 mg | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
Table 2 COLCRYS Dose Adjustment for Co-administration with Protease Inhibitors| Protease Inhibitor | Clinical Comment | w/Colchicine – Prophylaxis of Gout Flares | w/Colchicine – Treatment of Gout Flares | w/Colchicine – Treatment of FMF |
|---|
Atazanavir sulfate (Reyataz) | Patients with renal or hepatic impairment should not be given colchicine with Reyataz. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Darunavir (Prezista) | Patients with renal or hepatic impairment should not be given colchicine with Prezista/ritonavir. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Fosamprenavir (Lexiva) with Ritonavir | Patients with renal or hepatic impairment should not be given colchicine with Lexiva/ritonavir. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Fosamprenavir (Lexiva) | Patients with renal or hepatic impairment should not be given colchicine with Lexiva/ritonavir. | Original dose | Adjusted dose | 1.2 mg (2 tablets) × 1 dose. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 1.2 mg (may be given as 0.6 mg twice a day) |
| 0.6 mg twice a day | 0.3 mg twice a day or 0.6 mg once a day |
| 0.6 mg once a day | 0.3 mg once a day |
| Indinavir (Crixivan) | Patients with renal or hepatic impairment should not be given colchicine with Crixivan. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Lopinavir/Ritonavir (Kaletra) | Patients with renal or hepatic impairment should not be given colchicine with Kaletra. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Nelfinavir mesylate (Viracept) | Patients with renal or hepatic impairment should not be given colchicine with Viracept. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Ritonavir (Norvir) | Patients with renal or hepatic impairment should not be given colchicine with Norvir. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
| Saquinavir mesylate (Invirase) | Patients with renal or hepatic impairment should not be given colchicine with Invirase/ritonavir. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
Tipranavir (Aptivus)
| Patients with renal or hepatic impairment should not be given colchicine with Aptivus/ritonavir. | Original dose | Adjusted dose | 0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (1/2 tablet) 1 hour later. Dose to be repeated no earlier than 3 days. | Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day) |
0.6 mg twice a day
0.6 mg once a day | 0.3 mg once a day
0.3 mg once every other day |
Treatment of gout flares with COLCRYS is not recommended in patients receiving prophylactic dose of COLCRYS and CYP3A4 inhibitors.
Gout Flares:
Prophylaxis of Gout Flares:
For prophylaxis of gout flares in patients with mild (estimated creatinine clearance Clcr 50 – 80 mL/min) to moderate (Clcr 30 – 50 mL/min) renal function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of colchicine. However, in patients with severe impairment, the starting dose should be 0.3 mg per day and any increase in dose should be done with close monitoring. For the prophylaxis of gout flares in patients undergoing dialysis, the starting doses should be 0.3 mg given twice a week with close monitoring [see Clinical Pharmacology (12.3) and Renal Impairment (8.6)].
Treatment of Gout Flares:
For treatment of gout flares in patients with mild (Clcr 50 – 80 mL/min) to moderate (Clcr 30 – 50 mL/min) renal function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of colchicine. However, in patients with severe impairment, while the dose does not need to be adjusted for the treatment of gout flares, a treatment course should be repeated no more than once every 2 weeks. For patients with gout flares requiring repeated courses consideration should be given to alternate therapy. For patients undergoing dialysis, the total recommended dose for the treatment of gout flares should be reduced to a single dose of 0.6 mg (1 tablet). For these patients, the treatment course should not be repeated more than once every 2 weeks [see Clinical Pharmacology (12.3) and Renal Impairment (8.6)].
Treatment of gout flares with COLCRYS is not recommended in patients with renal impairment who are receiving COLCRYS for prophylaxis.
FMF:
Caution should be taken in dosing patients with moderate and severe renal impairment and in patients undergoing dialysis. For these patients, the dosage should be reduced [see Clinical Pharmacology (12.3)]. Patients with mild (Clcr 50 – 80 mL/min) and moderate (Clcr 30 – 50 mL/min) renal impairment should be monitored closely for adverse effects of COLCRYS. Dose reduction may be necessary. For patients with severe renal failure (Clcr less than 30 mL/minute), start with 0.3 mg/day; any increase in dose should be done with adequate monitoring of the patient for adverse effects of colchicine [see Renal Impairment (8.6)]. For patients undergoing dialysis, the total recommended starting dose should be 0.3 mg (half tablet) per day. Dosing can be increased with close monitoring. Any increase in dose should be done with adequate monitoring of the patient for adverse effects of colchicine [see Clinical Pharmacology (12.3) and Renal Impairment (8.6)].
Gout Flares
Prophylaxis of Gout Flares:
For prophylaxis of gout flares in patients with mild to moderate hepatic function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of colchicine. Dose reduction should be considered for the prophylaxis of gout flares in patients with severe hepatic impairment [see Hepatic Impairment (8.7)].
Treatment of Gout Flares:
For treatment of gout flares in patients with mild to moderate hepatic function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of colchicine. However, for the treatment of gout flares in patients with severe impairment while the dose does not need to be adjusted, but a treatment course should be repeated no more than once every 2 weeks. For these patients, requiring repeated courses for the treatment of gout flares, consideration should be given to alternate therapy [see Hepatic Impairment (8.7)].
Treatment of gout flares with COLCRYS is not recommended in patients with hepatic impairment who are receiving COLCRYS for prophylaxis.
FMF:
Patients with mild to moderate hepatic impairment should be monitored closely for adverse effects of colchicine. Dose reduction should be considered in patients with severe hepatic impairment [see Hepatic Impairment (8.7)].
Prophylaxis of Gout Flares:
The most commonly reported adverse reaction in clinical trials of colchicine for the prophylaxis of gout was diarrhea.
Treatment of Gout Flares:
The most common adverse reactions reported in the clinical trial with COLCRYS for treatment of gout flares were diarrhea (23%) and pharyngolaryngeal pain (3%).
FMF:
Gastrointestinal tract adverse effects are the most frequent side effects in patients initiating COLCRYS, usually presenting within 24 hours, and occurring in up to 20% of patients given therapeutic doses. Typical symptoms include cramping, nausea, diarrhea, abdominal pain, and vomiting. These events should be viewed as dose-limiting if severe as they can herald the onset of more significant toxicity.
Prophylaxis of Gout Flares:
For prophylaxis of gout flares in patients with mild (estimated creatinine clearance Clcr 50 – 80 mL/min) to moderate (Clcr 30 – 50 mL/min) renal function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of colchicine. However, in patients with severe impairment, the starting dose should be 0.3 mg per day and any increase in dose should be done with close monitoring. For the prophylaxis of gout flares in patients undergoing dialysis, the starting doses should be 0.3 mg given twice a week with close monitoring [see Dose Modification in Renal Impairment (2.5)].
Treatment of Gout Flares:
For treatment of gout flares in patients with mild (Clcr 50 – 80 mL/min) to moderate (Clcr 30 – 50 mL/min) renal function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of COLCRYS. However, in patients with severe impairment, while the dose does not need to be adjusted for the treatment of gout flares, a treatment course should be repeated no more than once every 2 weeks. For patients with gout flares requiring repeated courses consideration should be given to alternate therapy. For patients undergoing dialysis, the total recommended dose for the treatment of gout flares should be reduced to a single dose of 0.6 mg (1 tablet). For these patients, the treatment course should not be repeated more than once every 2 weeks [see Dose Modification in Renal Impairment (2.5)].
FMF
Although, pharmacokinetics of colchicine in patients with mild (Clcr 50 – 80 mL/min) and moderate (Clcr 30 – 50 mL/min) renal impairment is not known, these patients should be monitored closely for adverse effects of colchicine. Dose reduction may be necessary. In patients with severe renal failure (Clcr less than 30 mL/minute) and end-stage renal disease requiring dialysis, COLCRYS may be started at the dose of 0.3 mg/day. Any increase in dose should be done with adequate monitoring of the patient for adverse effects of COLCRYS [see Pharmacokinetics (12.3) and Dose Modification in Renal Impairment (2.5)].
Prophylaxis of Gout Flares:
For prophylaxis of gout flares in patients with mild to moderate hepatic function impairment, adjustment of the recommended dose is not required, but patients should be monitored closely for adverse effects of colchicine. Dose reduction should be considered for the prophylaxis of gout flares in patients with severe hepatic impairment [see Dose Modification in Hepatic Impairment (2.6)].
Treatment of Gout Flares:
For treatment of gout flares in patients with mild to moderate hepatic function impairment, adjustment of the recommended COLCRYS dose is not required, but patients should be monitored closely for adverse effects of COLCRYS. However, for the treatment of gout flares in patients with severe impairment while the dose does not need to be adjusted, the treatment course should be repeated no more than once every 2 weeks. For these patients, requiring repeated courses for the treatment of gout flares, consideration should be given to alternate therapy [see Dose Modification in Hepatic Impairment (2.6)].
FMF
In patients with severe hepatic disease, dose reduction should be considered with careful monitoring [see Pharmacokinetics (12.3) and Dose Modification in Hepatic Impairment (2.6)].
Absorption
In healthy adults, COLCRYS is absorbed when given orally, reaching a mean Cmax of 2.5 ng/mL (range 1.1 to 4.4 ng/mL) in 1 to 2 hours (range 0.5 to 3 hours) after a single dose administered under fasting conditions.
Following oral administration of COLCRYS given as 1.8 mg colchicine over 1 hour to healthy, young adults under fasting conditions, colchicine appears to be readily absorbed, reaching mean maximum plasma concentrations of 6.2 ng/mL at a median 1.81 hours (range: 1.0 to 2.5 hours). Following administration of the non-recommended high-dose regimen (4.8 mg over 6 hours), mean maximal plasma concentrations were 6.8 ng/mL, at a median 4.47 hours (range: 3.1 to 7.5 hours).
After 10 days on a regimen of 0.6 mg twice daily, peak concentrations are 3.1 to 3.6 ng/mL (range 1.6 to 6.0 ng/mL), occurring 1.3 to 1.4 hours post-dose (range 0.5 to 3.0 hours). Mean pharmacokinetic parameter values in healthy adults are shown in Table 5 below.
Table 5 Mean (%CV) Pharmacokinetic Parameters in Healthy Adults Given COLCRYS| Cmax (colchicine ng/mL) | Tmax Tmax mean (range) (h) | Vd/F (L) | CL/F (L/hr) | t1/2 (h) |
|---|
CL= Dose/AUC0-t (Calculated from mean values) Vd = CL/Ke (Calculated from mean values) |
| COLCRYS 0.6 mg Single Dose (N=13) |
| 2.5 (28.7) | 1.5 (1.0 – 3.0) | 341.5 (54.4) | 54.1 (31.0) | -- |
| COLCRYS 0.6 mg b.i.d. × 10 days (N=13) |
| 3.6 (23.7) | 1.3 (0.5 – 3.0) | 1150 (18.7) | 30.3 (19.0) | 26.6 (16.3) |
In some subjects, secondary colchicine peaks are seen, occurring between 3 and 36 hours post-dose and ranging from 39% to 155% of the height of the initial peak. These observations are attributed to intestinal secretion and reabsorption and/or biliary recirculation.
Absolute bioavailability is reported to be approximately 45%.
Administration of COLCRYS with food has no effect on the rate of colchicine absorption, but did decrease the extent of colchicine by approximately 15%. This is without clinical significance.
Distribution
The mean apparent volume of distribution in healthy young volunteers was approximately 5 to 8 L/kg.
Colchicine binding to serum protein is low, 39 ± 5%, primarily to albumin regardless of concentration.
Colchicine crosses the placenta (plasma levels in the fetus are reported to be approximately 15% of the maternal concentration). Colchicine also distributes into breast milk at concentrations similar to those found in the maternal serum [see Pregnancy (8.1) and Nursing Mothers (8.3)].
Metabolism
Colchicine is demethylated to two primary metabolites, 2-O-demethylcolchicine and 3-O-demethylcolchicine (2- and 3-DMC, respectively), and one minor metabolite, 10-O-demethylcolchicine (also known as colchiceine). In vitro studies using human liver microsomes have shown that CYP3A4 is involved in the metabolism of colchicine to 2- and 3-DMC. Plasma levels of these metabolites are minimal (less than 5% of parent drug).
Elimination/Excretion
In healthy volunteers (n=12) 40 – 65% of 1 mg orally administered colchicine was recovered unchanged in urine. Enterohepatic recirculation and biliary excretion are also postulated to play a role in colchicine elimination. Following multiple oral doses (0.6 mg twice daily), the mean elimination half-lives in young healthy volunteers (mean age 25 to 28 years of age) is 26.6 to 31.2 hours. Colchicine is a substrate of P-gp.
Extracorporeal Elimination: Colchicine is not removed by hemodialysis.
Special Populations
There is no difference between men and women in the pharmacokinetic disposition of colchicine.
Pediatric Patients: Pharmacokinetics of colchicine was not evaluated in pediatric patients.
Elderly: Pharmacokinetics of colchicine has not been determined in elderly patients. A published report described the pharmacokinetics of 1 mg oral colchicine tablet in four elderly women compared to six young healthy males. The mean age of the four elderly women was 83 years (range 75 – 93), mean weight was 47 kg (38 – 61 kg) and mean creatinine clearance was 46 mL/min (range 25 – 75 mL/min). Mean peak plasma levels and AUC of colchicine were two times higher in elderly subjects compared to young healthy males. However, it is possible that the higher exposure in the elderly subjects was due to decreased renal function.
Renal impairment: Pharmacokinetics of colchicine in patients with mild and moderate renal impairment is not known. A published report described the disposition of colchicine (1 mg) in young adult men and women with FMF who had normal renal function or end-stage renal disease requiring dialysis. Patients with end-stage renal disease had 75% lower colchicine clearance (0.17 vs 0.73 L/hr/kg) and prolonged plasma elimination half-life (18.8 hrs vs 4.4 hrs) as compared to subjects with FMF and normal renal function [see Dose Modification in Renal Impairment (2.5) and Renal Impairment (8.6)].
Hepatic impairment: Published reports on the pharmacokinetics of IV colchicine in patients with severe chronic liver disease, as well as those with alcoholic or primary biliary cirrhosis, and normal renal function suggest wide inter-patient variability. In some subjects with mild to moderate cirrhosis, the clearance of colchicine is significantly reduced and plasma half-life prolonged compared to healthy subjects. In subjects with primary biliary cirrhosis, no consistent trends were noted [see Dose Modification in Hepatic Impairment (2.6) and Hepatic Impairment (8.7)]. No pharmacokinetic data are available for patients with severe hepatic impairment (Child-Pugh C).
Drug interactions:
In vitro drug interactions:
In vitro studies in human liver microsomes have shown that colchicine is not an inhibitor or inducer of CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, or CYP3A4 activity.
In vivo drug interactions:
The effects of co-administration of other drugs with COLCRYS on Cmax, AUC, and Cmin are summarized in Table 6 (effect of other drugs on colchicine) and Table 7 (effect of colchicine on other drugs). For information regarding clinical recommendations, see Table 1 in Dose Modification for Co-administration of Interacting Drugs [see Dose Modification for Co-administration of Interacting Drugs (2.4)].
Table 6 Drug Interactions: Pharmacokinetic Parameters for COLCRYS (colchicine, USP) tablets in the Presence of the Co-Administered Drug | Co-administered Drug | Dose of Co-administered Drug (mg) | Dose of COLCRYS (mg) | N | % Change in Colchicine Concentrations from Baseline (Range: Min - Max) |
|---|
| | | | Cmax | AUC0-t |
|---|
| Cyclosporine | 100 mg single-dose | 0.6 mg single-dose | 23 | 270.0 (62.0 to 606.9) | 259.0 (75.8 to 511.9) |
| Clarithromycin | 250 mg BID, 7 days | 0.6 mg single-dose | 23 | 227.2 (65.7 to 591.1) | 281.5 (88.7 to 851.6) |
| Ketoconazole | 200 mg BID, 5 days | 0.6 mg single-dose | 24 | 101.7 (19.6 to 219.0) | 212.2 (76.7 to 419.6) |
| Ritonavir | 100 mg BID, 5 days | 0.6 mg single-dose | 18 | 184.4 (79.2 to 447.4) | 296.0 (53.8 to 924.4) |
| Verapamil | 240 mg daily, 5 days | 0.6 mg single-dose | 24 | 40.1 (-47.1 to 149.5) | 103.3 (-9.8 to 217.2) |
| Diltiazem | 240 mg daily, 7 days | 0.6 mg single-dose | 20 | 44.2 (-46.0 to 318.3) | 93.4 (-30.2 to 338.6) |
| Azithromycin | 500 mg × 1 day, then 250 mg × 4 days | 0.6 mg single-dose | 21 | 21.6 (-41.7 to 222.0) | 57.1 (-24.3 to 241.1) |
| Grapefruit Juice | 240 mL BID, 4 days | 0.6 mg single-dose | 21 | -2.55 (-53.4 to 55.0) | -2.36 (-46.4 to 62.2) |
Estrogen-containing oral contraceptives: In healthy female volunteers given ethinyl estradiol and norethindrone (Ortho-Novum® 1/35) co-administered with COLCRYS (0.6 mg b.i.d. × 14 days), hormone concentrations are not affected.
In healthy volunteers given theophylline co-administered with COLCRYS (0.6 mg b.i.d. × 14 days), theophylline concentrations were not affected.
Table 7 Drug Interactions: Pharmacokinetic Parameters for Co-Administration of Drug in the Presence of COLCRYS (colchicine, USP) tablets| Co-administered Drug | Dose of Co-administered Drug (mg) | Dose of COLCRYS (mg) | N | % Change in Co-Administered Drug Concentrations from Baseline (Range: Min - Max) |
|---|
| | | | Cmax | AUC0-t |
|---|
| Theophylline | 300 mg (elixir) single-dose | 0.6 mg BID × 14 days | 27 | 1.6 (-30.4 to 23.1) | 1.6 (-28.5 to 27.1) |
| Ethinyl Estradiol (Ortho-Novum® 1/35) | 21-Day Cycle (Active Treatment) + 7-Day Placebo | 0.6 mg BID × 14 days | 27 Conducted in healthy adult females | -6.7 (-40.3 to 44.7) | -3.0 AUCτ (-25.3 to 24.9) |
| Norethindrone (Ortho-Novum® 1/35) | 0.94 (-37.3 to 59.4) | -1.6 (-32.0 to 33.7) |