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VIOXX (rofecoxib tablets and oral suspension) 9556413 Hepatic Effects Borderline elevations of one or more liver tests may occur in up to 15% of patients taking NSAIDs, and notable elevations of ALT or AST (approximately three or more times the upper limit of normal) have been reported in approximately 1% of patients in clinical trials with NSAIDs. These laboratory abnormalities may progress, may remain unchanged, or may be transient with continuing therapy. Rare cases of severe hepatic reactions, including jaundice and fatal fulminant hepatitis, liver necrosis and hepatic failure (some with fatal outcome) have been reported with NSAIDs, including VIOXX. Text Continues Below
In controlled clinical trials of VIOXX, the incidence of borderline elevations of liver tests at doses of 12.5 and 25 mg daily was comparable to the incidence observed with ibuprofen and lower than that observed with diclofenac. In placebo-controlled trials, approximately 0.5% of patients taking rofecoxib (12.5 or 25 mg QD) and 0.1% of patients taking placebo had notable elevations of ALT or AST. A patient with symptoms and/ or signs suggesting liver dysfunction, or in whom an abnormal liver test has occurred, should be monitored carefully for evidence of the development of a more severe hepatic reaction while on therapy with VIOXX. The maximum recommended chronic daily dose in patients with moderate hepatic insufficiency is 12.5 mg daily. Use of VIOXX is not recommended in patients with severe hepatic insufficiency (see CLINICAL PHARMACOLOGY, Special Populations and DOSAGE AND ADMINISTRATION, Hepatic Insufficiency). If clinical signs and symptoms consistent with liver disease develop, or if systemic manifestations occur (e. g., eosinophilia, rash, etc.), VIOXX should be discontinued. Hematological Effects Anemia is sometimes seen in patients receiving VIOXX. In placebo-controlled trials, there were no significant differences observed between VIOXX and placebo in clinical reports of anemia. Patients on long-term treatment with VIOXX should have their hemoglobin or hematocrit checked if they exhibit any signs or symptoms of anemia or blood loss. VIOXX does not generally affect platelet counts, prothrombin time (PT), or partial thromboplastin time (PTT), and does not inhibit platelet aggregation at indicated dosages (see CLINICAL STUDIES, Special Studies, Platelets). Preexisting Asthma Patients with asthma may have aspirin-sensitive asthma. The use of aspirin in patients with aspirin-sensitive asthma has been associated with severe bronchospasm which can be fatal. Since cross reactivity, including bronchospasm, between aspirin and other nonsteroidal anti-inflammatory drugs has been reported in such aspirin-sensitive patients, VIOXX should not be administered to patients with this form of aspirin sensitivity and should be used with caution in patients with preexisting asthma. Information for Patients Physicians should instruct their patients to read the patient package insert before starting therapy with VIOXX and to reread it each time the prescription is renewed in case any information has changed. VIOXX can cause discomfort and, rarely, more serious side effects, such as gastrointestinal bleeding, which may result in hospitalization and even fatal outcomes. Although serious GI tract ulcerations and bleeding can occur without warning symptoms, patients should be alert for the signs and symptoms of ulcerations and bleeding, and should ask for medical advice when observing any indicative signs or symptoms. Patients should be apprised of the importance of this follow-up. For additional gastrointestinal safety information see CLINICAL STUDIES, Special Studies, VIGOR and WARNINGS, Gastrointestinal (GI) Effects -Risk of GI Ulceration, Bleeding and Perforation. Patients should be informed that VIOXX is not a substitute for aspirin for cardiovascular prophylaxis because of its lack of effect on platelets. For additional cardiovascular safety information see CLINICAL STUDIES, Special Studies, VIGOR and PRECAUTIONS, Cardiovascular Effects. Patients should promptly report signs or symptoms of gastrointestinal ulceration or bleeding, skin rash, unexplained weight gain, edema or chest pain to their physicians. Patients should be informed of the warning signs and symptoms of hepatotoxicity (e. g., nausea, fatigue, lethargy, pruritus, jaundice, right upper quadrant tenderness, and "flu-like" symptoms). If these occur, patients should be instructed to stop therapy and seek immediate medical therapy. Patients should also be instructed to seek immediate emergency help in the case of an anaphylactoid reaction (see WARNINGS). In late pregnancy VIOXX should be avoided because it may cause premature closure of the ductus
arteriosus. Laboratory Tests Because serious GI tract ulcerations and bleeding can occur without warning symptoms, physicians should monitor for signs or symptoms of GI bleeding. Drug Interactions ACE inhibitors Reports suggest that NSAIDs may diminish the antihypertensive effect of Angiotensin Converting Enzyme (ACE) inhibitors. In patients with mild to moderate hypertension, administration of 25 mg daily of VIOXX with the ACE inhibitor benazepril, 10 to 40 mg for 4 weeks, was associated with an average increase in mean arterial pressure of about 3 mm Hg compared to ACE inhibitor alone. This interaction should be given consideration in patients taking VIOXX concomitantly with ACE inhibitors. Aspirin Concomitant administration of low-dose aspirin with VIOXX may result in an increased rate of GI ulceration or other complications, compared to use of VIOXX alone. In a 12-week endoscopy study conducted in OA patients there was no difference in the cumulative incidence of endoscopic gastroduodenal ulcers in patients taking low-dose (81 mg) enteric coated aspirin plus VIOXX 25 mg daily, as compared to those taking ibuprofen 2400 mg daily alone. Patients taking low-dose aspirin plus ibuprofen were not studied. (See CLINICAL STUDIES, Special Studies, Upper Endoscopy in Patients with Osteoarthritis and Rheumatoid Arthritis.) At steady state, VIOXX 50 mg once daily had no effect on the anti-platelet activity of low-dose (81 mg once daily) aspirin, as assessed by ex vivo platelet aggregation and serum TXB2 generation in clotting blood. Because of its lack of platelet effects, VIOXX is not a substitute for aspirin for cardiovascular prophylaxis. Therefore, in patients taking VIOXX, antiplatelet therapies should not be discontinued and should be considered in patients with an indication for cardiovascular prophylaxis. (See CLINICAL STUDIES, Special Studies, Platelets and PRECAUTIONS, Cardiovascular Effects.) Prospective, long-term studies on concomitant administration of VIOXX and aspirin have not been conducted. Cimetidine Co-administration with high doses of cimetidine [800 mg twice daily] increased the Cmax of rofecoxib by 21%, the AUC0-120hr by 23% and the t1/ 2 by 15%. These small changes are not clinically significant and no dose adjustment is necessary. Digoxin Rofecoxib 75 mg once daily for 11 days does not alter the plasma concentration profile or renal elimination of digoxin after a single 0.5 mg oral dose. Furosemide: Clinical studies, as well as post-marketing observations, have shown that NSAIDs can reduce the natriuretic effect of furosemide and thiazides in some patients. This response has been attributed to inhibition of renal prostaglandin synthesis. Ketoconazole Ketoconazole 400 mg daily did not have any clinically important effect on the pharmacokinetics of rofecoxib. Lithium: NSAIDs have produced an elevation of plasma lithium levels and a reduction in renal lithium clearance. In post-marketing experience there have been reports of increases in plasma lithium levels. Thus, when VIOXX and lithium are administered concurrently, subjects should be observed carefully for signs of lithium toxicity. Methotrexate VIOXX 12.5, 25, and 50 mg, each dose administered once daily for 7 days, had no effect on the plasma concentration of methotrexate as measured by AUC0-24hr in patients receiving single weekly methotrexate doses of 7.5 to 20 mg for rheumatoid arthritis. At higher than recommended doses, VIOXX 75 mg administered once daily for 10 days increased plasma concentrations by 23% as measured by AUC0-24hr in patients receiving methotrexate 7.5 to 15 mg/ week for rheumatoid arthritis. At 24 hours postdose, a similar proportion of patients treated with methotrexate alone (94%) and subsequently treated with methotrexate co-administered with 75 mg of rofecoxib (88%) had methotrexate plasma concentrations below the measurable limit (5 ng/ mL). Standard monitoring of methotrexate-related toxicity should be continued if VIOXX and methotrexate are administered concomitantly. Oral Contraceptives Rofecoxib did not have any clinically important effect on the pharmacokinetics of ethinyl estradiol and norethindrone. Prednisone/ prednisolone Rofecoxib did not have any clinically important effect on the pharmacokinetics of prednisolone or prednisone. Rifampin: Co-administration of VIOXX with rifampin 600 mg daily, a potent inducer of hepatic metabolism, produced an approximate 50% decrease in rofecoxib plasma concentrations. Therefore, a starting daily dose of 25 mg of VIOXX should be considered for the treatment of osteoarthritis when VIOXX is co-administered with potent inducers of hepatic metabolism. Theophylline: VIOXX 12.5, 25, and 50 mg administered once daily for 7 days increased plasma theophylline concentrations (AUC( 0- )) by 38 to 60% in healthy subjects administered a single 300-mg dose of theophylline. Adequate monitoring of theophylline plasma concentrations should be considered when therapy with VIOXX is initiated or changed in patients receiving theophylline. These data suggest that rofecoxib may produce a modest inhibition of cytochrome P450 (CYP) 1A2. Therefore, there is a potential for an interaction with other drugs that are metabolized by CYP 1A2 (e. g., amitriptyline, tacrine, and zileuton). Warfarin Anticoagulant activity should be monitored, particularly in the first few days after initiating or changing VIOXX therapy in patients receiving warfarin or similar agents, since these patients are at an increased risk of bleeding complications. In single and multiple dose studies in healthy subjects receiving both warfarin and rofecoxib, prothrombin time (measured as INR) was increased by approximately 8% to 11%. In post-marketing experience, bleeding events have been reported, predominantly in the elderly, in association with increases in prothrombin time in patients receiving VIOXX concurrently with warfarin. Carcinogenesis, Mutagenesis, Impairment of Fertility Rofecoxib was not carcinogenic in mice given oral doses up to 30 mg/ kg (male) and 60 mg/ kg (female) (approximately 5-and 2-fold the human exposure at 25 and 50 mg daily based on AUC0-24) and in male and female rats given oral doses up to 8 mg/ kg (approximately 6-and 2-fold the human exposure at 25 and 50 mg daily based on AUC0-24) for two years. Rofecoxib was not mutagenic in an Ames test or in a V-79 mammalian cell mutagenesis assay, nor clastogenic in a chromosome aberration assay in Chinese hamster ovary (CHO) cells, in an in vitro and an in vivo alkaline elution assay, or in an in vivo chromosomal aberration test in mouse bone marrow. Rofecoxib did not impair male fertility in rats at oral doses up to 100 mg/ kg (approximately 20-and 7-fold human exposure at 25 and 50 mg daily based on the AUC0-24) and rofecoxib had no effect on fertility in female rats at doses up to 30 mg/ kg (approximately 19-and 7-fold human exposure at 25 and 50 mg daily based on AUC0-24). Pregnancy Teratogenic effects Pregnancy Category C. Rofecoxib was not teratogenic in rats at doses up to 50 mg/ kg/ day (approximately 28-and 10-fold human exposure at 25 and 50 mg daily based on AUC0-24). There was a slight, non-statistically significant increase in the overall incidence of vertebral malformations only in the rabbit at doses of 50 mg/ kg/ day (approximately 1-or <1-fold human exposure at 25 and 50 mg daily based on AUC0-24). There are no studies in pregnant women. VIOXX should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Nonteratogenic effects Rofecoxib produced peri-implantation and post-implantation losses and reduced embryo/ fetal survival in rats and rabbits at oral doses 10 and 75 mg/ kg/ day, respectively (approximately 9-and 3-fold [rats] and 2-and <1-fold [rabbits] human exposure based on the AUC0-24 at 25 and 50 mg daily). These changes are expected with inhibition of prostaglandin synthesis and are not the result of permanent alteration of female reproductive function. There was an increase in the incidence of postnatal pup mortality in rats at 5 mg/ kg/ day (approximately 5-and 2-fold human exposure at 25 and 50 mg daily based on AUC0-24). In studies in pregnant rats administered single doses of rofecoxib, there was a treatment-related decrease in the diameter of the ductus arteriosus at all doses used (3-300 mg/ kg: 3 mg/ kg is approximately 2-and <1-fold human exposure at 25 or 50 mg daily based on AUC0-24). As with other drugs known to inhibit prostaglandin synthesis, use of VIOXX during the third trimester of pregnancy should be avoided. Labor and delivery Rofecoxib produced no evidence of significantly delayed labor or parturition in females at doses 15 mg/ kg in rats (approximately 10-and 3-fold human exposure as measured by the AUC0-24 at 25 and 50 mg). The effects of VIOXX on labor and delivery in pregnant women are unknown. Merck & Co., Inc. maintains a registry to monitor the pregnancy outcomes of women exposed to VIOXX while pregnant. Healthcare providers are encouraged to report any prenatal exposure to VIOXX by calling the Pregnancy Registry at (800) 986-8999. Nursing mothers Rofecoxib is excreted in the milk of lactating rats at concentrations similar to those in plasma. There was an increase in pup mortality and a decrease in pup body weight following exposure of pups to milk from dams administered VIOXX during lactation. The dose tested represents an approximate 18-and 6-fold human exposure at 25 and 50 mg based on AUC0-24. It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from VIOXX, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Pediatric Use
Safety and effectiveness in pediatric patients below the age of 18 years have not been evaluated. Geriatric Use Of the patients who received VIOXX in osteoarthritis clinical trials, 1455 were 65 years of age or older. This included 460 patients who were 75 years or older, and in one of these studies, 174 patients who were 80 years or older. No substantial differences in safety and effectiveness were observed between these subjects and younger subjects. Greater sensitivity of some older individuals cannot be ruled out. As with
other NSAIDs, including those that selectively inhibit COX-2, there have been more spontaneous post-marketing reports of fatal GI events and acute renal failure in the elderly than in younger patients. Dosage adjustment in the elderly is not necessary; however, therapy with VIOXX should be initiated at the lowest recommended dose. Page: << Prev | 1 | 2 | 3 | 4 | 5
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