Spontaneous Reports of Hypertension Leading to Hospitalisation in Association with Rofecoxib, Celecoxib, Nabumetone and Oxaprozin

Influence of celecoxib on the vasodilating properties of human mesenteric arteries constricted with endothelin-1

The mitogenic and vasoconstrictive properties of the vascular system are attributed to endothelin-1 (ET-1). ET-1 serum concentration increases in a number of pathological conditions, particularly in those associated with blood vessel constriction. ET-1 is also associated with the underlying pathomechanisms of primary pulmonary hypertension, arterial hypertension and eclampsia. The aim of this study was to compare the vasodilating properties of selected phosphodiesterase (PDE) inhibitors and celecoxib in human mesenteric arteries constricted with ET-1, and investigate the role of the endothelium in relaxation. Perfused human mesenteric arteries were collected and stored under the same conditions as organs for transplantation. The mesenteric arteries (with and without the endothelium) were constricted by the addition of ET-1 and treated with one of the following: sildenafil (PDE5 inhibitor), zaprinast (PDE5 and 6 inhibitor), rolipram (PDE4 inhibitor) and celecoxib [cyclooxygenase-2 (COX-2) inhibitor]. Based on the observed changes of the perfusion pressure, concentration response curves (CRCs) were prepared for the respective inhibitors and the EC₅₀ (concentration causing an effect equal to half of the maximum effect), pD₂ (negative common logarithm of EC₅₀) and relative potency (RP) were calculated. The results suggested that all the inhibitors triggered a concentration-dependent decrease in the perfusion pressure in isolated human superior mesenteric arteries with endothelium constricted by the addition of ET-1. In the arteries without endothelium, CRCs for celecoxib and rolipram were shifted to the right without a significant decrease in the maximum dilating effect. Moreover, CRCs for sildenafil and zaprinast were shifted to the right with a simultaneous significant decrease in the maximum dilating effect and with an increased inclination angle in reference to the concentration axis. In the presence of the endothelium, all of the evaluated PDE inhibitors, as well as celecoxib, reduced the reactivity of the mesenteric arteries caused by ET-1. Sildenafil indicated the lowest efficacy in the presence of the endothelium, but showed a higher potency compared to that of the other compounds. Removing the endothelium significantly reduced the vasodilating efficacy of PDE5 and 6 inhibitors and a statistically significant influence on the vasodilating efficacy of PDE4 inhibitor and celecoxib was observed. The high vasorelaxing efficacy of celecoxib at the background of the PDE inhibitors was observed, not only in the presence, but also in the absence of the endothelium and may be evidence for the relaxation induced by this COX-2 inhibitor in the cAMP- and cGMP-dependent pathways.

Cyclooxygenase inhibitors: scope of their use and development in cancer chemotherapy

The traditional nonsteroidal anti-inflammatory drugs (NSAIDs) exert their effect by inhibition of cyclooxygenase-1 (COX-1) as well as COX-2 enzymes. As COX-1 is responsible for maintaining normal biological functions, the nonselective inhibition of these enzymes caused side effects including gastrointestinal (GI) problems. Recently developed selective COX-2 inhibitors could reduce these adverse effects, but the evidence of cardiovascular side effects including an increased risk of myocardial infarction began to emerge, and some of the COX-2 inhibitors were eventually withdrawn from the market and this led to the downfall of this research. So, the discovery of novel COX-2 inhibitors with their safety profile became the biggest challenge in pharmaceutical research. However, recent mechanistic and clinical studies revolutionized this area by indicating the fact that COX-2 is involved in apoptosis resistance, angiogenesis, and tumor progression. Epidemiological data suggest that selective COX-2 inhibitors might prevent the development of cancers. Moreover, COX-2 is found to be overexpressed in many cancers thus making it an attractive therapeutic target for the prevention and treatment of a number of malignancies. The purpose of this review is to focus on the medicinal chemistry aspects of COX-2 inhibitors in cancer chemotherapy and recent reports on these inhibitors as anticancer agents. We attempted to cover only the COX inhibitors that showed anticancer activity, although a number of potent COX-2 inhibitors have been reported without their anticancer effects. Furthermore, structure-activity relationships (SAR) of different classes of compounds for COX-2 inhibition as well as anticancer activity, and their future applications are discussed.

Case series in drug safety: a review to determine characteristics and quality

Case series and case reports are a cornerstone of drug safety research; however, the characteristics of case series published in the literature remain poorly examined. A narrative review of case series addressing drug safety, published in the literature between 1 January 2003 and 15 July 2009, and identified through a PubMed search, was conducted in order to determine their characteristics and quality according to the criteria found in the US FDA Pharmacovigilance Guidance 2005. Of 130 publications that met the search criteria, 11.5% included an analytical component and 88.5% were descriptive. The median number of cases included in a given case series was 7 (range 2-2195) and the median time period for recruitment of the cases was 23 months (range 0.5-96). Overall, 43.1% of case series consisted of individual case reports, while 24.6% originated from cohorts and 21% from pharmacovigilance databases. Of the case series, 65.1% concerned adults (age ≥18 years), 11.6% elderly (age ≥65 years) and 8.5% youth (<18 years). Adverse effects involved mainly the skin (18.5%) and the circulatory system (13.8%). The main suspected drug classes (Anatomical Therapeutic Chemical classification) were nervous system drugs (23.1%) and antineoplastic and immunomodulating agents (20.0%). On average, six out of the possible nine US FDA Pharmacovigilance Guidance Criteria were fulfilled, with 27% of publications fulfilling at least seven criteria. Only 10% reported data on co-morbidity. In conclusion, this review highlights the reporting gaps and heterogeneity in published case series with respect to size, recruitment period and quality.

Information about ADRs explored by pharmacovigilance approaches: a qualitative review of studies on antibiotics, SSRIs and NSAIDs

Background

Despite surveillance efforts, unexpected and serious adverse drug reactions (ADRs) repeatedly occur after marketing. The aim of this article is to analyse ADRs reported by available ADR signal detection approaches and to explore which information about new and unexpected ADRs these approaches have detected.

Methods

We selected three therapeutic cases for the review: antibiotics for systemic use, non-steroidal anti-inflammatory medicines (NSAID) and selective serotonin re-uptake inhibitors (SSRI). These groups are widely used and represent different therapeutic classes of medicines. The ADR studies were identified through literature search in Medline and Embase. The search was conducted in July 2007. For each therapeutic case, we analysed the time of publication, the strengths of the evidence of safety in the different approaches, reported ADRs and whether the studies have produced new information about ADRs compared to the information available at the time of marketing.

Results

79 studies were eligible for inclusion in the analysis: 23 antibiotics studies, 35 NSAID studies, 20 SSRI studies. Studies were mainly published from the end of the 1990s and onwards. Although the drugs were launched in different decades, both analytical and observational approaches to ADR studies were similar for all three therapeutic cases: antibiotics, NSAIDs and SSRIs. The studies primarily dealt with analyses of ADRs of the type A and B and to a lesser extent C and D, cf. Rawlins' classification system. The therapeutic cases provided similar results with regard to detecting information about new ADRs despite different time periods and organs attacked. Approaches ranging higher in the evidence hierarchy provided information about risks of already known or expected ADRs, while information about new and previously unknown ADRs was only detected by case reports, the lowest ranking approach in the evidence hierarchy.

Conclusion

Although the medicines were launched in different decades, approaches to the ADR studies were similar for all three therapeutic cases: antibiotics, NSAIDs and SSRIs. Both descriptive and analytical designs were applied. Despite the fact that analytical studies rank higher in the evidence hierarchy, only the lower ranking descriptive case reports/spontaneous reports provided information about new and previously undetected ADRs. This review underscores the importance of systems for spontaneous reporting of ADRs. Therefore, spontaneous reporting should be encouraged further and the information in ADR databases should continuously be subjected to systematic analysis.

Safety of the nonselective NSAID nabumetone : focus on gastrointestinal tolerability

Although effective in the treatment of pain associated with rheumatic conditions such as osteoarthritis and rheumatoid arthritis, long-term use of NSAIDs is primarily limited by their association with upper gastrointestinal (GI) toxicity. Adverse effects range from dyspepsia and abdominal pain to ulceration and bleeding. GI damage elicited by NSAIDs arises as the result of biochemically induced topical irritant effects and by topical and systemic pharmacological suppression of gastroprotective prostaglandins. Variation in the physicochemical properties and pharmacological profiles among the individual NSAIDs translate into inter-agent differences regarding propensity to cause adverse GI effects. Nabumetone is a nonselective NSAID that offers distinct advantages over other agents in this class with regard to GI tolerability. Its non-acidic nature and pro-drug formulation, together with the lack of biliary secretion of its active metabolite, 6-methoxy-2-naphthylacetic acid, are thought to contribute to the improved GI tolerability of this drug. In head-to-head trials with other NSAIDs, nabumetone has demonstrated significant benefits regarding the incidence of GI events and more serious perforations, ulcers and bleeds (PUBs). Pooled data from eight postmarketing, randomized, controlled trials demonstrated a lower cumulative frequency of PUBs with nabumetone (0.03%; 95% CI 0.0, 0.08) versus comparator NSAIDs (1.4%; 95% CI 0.5, 2.4). Large-scale database studies also indicate that risk of serious GI complications is lower with nabumetone than comparator NSAIDs. Limited comparative data suggest that nabumetone offers a GI tolerability profile similar to that of cyclo-oxygenase-2 selective NSAIDs (coxibs). Although adverse cardiovascular outcomes appear to be a class effect of the coxibs, conventional NSAIDs may also have the potential for causing atherothrombotic complications. However, based on available data, nabumetone does not appear to be associated with increased cardiovascular risk. Finally, there is no particular concern about the nephrotoxic and hepatotoxic potential of nabumetone. Nonetheless, the potential for adverse drug reactions remains, and hence nabumetone, as with any NSAID, should be used at the lowest dose, which is effective for each patient, and for the shortest time necessary to control symptoms.

Mechanism for Covalent Binding of Rofecoxib to Elastin of Rat Aorta

We have previously reported that oral administration of [(14)C]rofecoxib to rats resulted in the long retention of radioactivity by the aorta as a consequence of covalent binding to elastin. Treatment of rats with alpha-phenyl-alpha-propylbenzeneacetic acid 2-[diethylamino]-ethyl ester hydrochloride (SKF-525A), a cytochrome P450 inhibitor, significantly decreased the systemic exposure of 5-hydroxyrofecoxib, one of the main metabolites of rofecoxib, whereas there was no statistically significant change in the retention of radioactivity from [(14)C]rofecoxib in the aorta. On the other hand, the aortic retention of radioactivity closely correlated to the systemic exposure of unchanged rofecoxib in the dose range between 2 and 10 mg/kg. A covalent binding study of [(14)C]rofecoxib in vitro using rat aorta homogenate in the presence of d-penicillamine, hydralazine, beta-aminopropionitrile, and sodium borohydride suggested that the aldehyde group of allysine in elastin was relevant to the covalent binding. In a model reaction using benzaldehyde, rofecoxib but not 5-hydroxyrofecoxib reacted with the aldehyde group of benzaldehyde in a manner of condensation reaction under a physiological pH condition. A histopathological examination using an electron microscope demonstrated that multiple oral administration of rofecoxib to rats caused marked degradation of the elastic fiber system of the aorta. These results suggested that rofecoxib as such is reactive in vivo, undergoing a condensation reaction with allysine, thereby preventing the formation of cross-linkages in elastin, i.e., desmosine and isodesmosine, and causing the degradation of the elastic fibers.

Rofecoxib 12.5 mg, rofecoxib 25 mg, and celecoxib 200 mg in the treatment of symptomatic osteoarthritis: results of two similarly designed studies

OBJECTIVE

To compare the efficacy of rofecoxib and celecoxib for the treatment of knee or hip OA over 6 weeks.

METHODS

Two similarly designed, multicenter, randomized, double-blind, placebo-controlled studies. Patients were randomly assigned 3:3:3:1 in Study 1 to once daily (QD) rofecoxib 12.5 mg (N = 456), rofecoxib 25 mg (N = 459), celecoxib 200 mg (N = 456), or placebo (N = 150) and 3:3:1 in Study 2 to QD rofecoxib 25 mg (N = 471), celecoxib 200 mg (N = 460), or placebo (N = 151). There was no rofecoxib 12.5 mg arm in Study 2. The primary outcome measure of both studies was pain at night over 6 weeks for rofecoxib 25 mg vs. celecoxib 200 mg. Efficacy comparisons with rofecoxib 12.5 mg in Study 1 were included as pre-specified study objectives but not as pre-specified study hypotheses. Secondary endpoints included Patient Global Assessment of Response to Therapy (PGART) over 6 weeks and over 1 week. Safety was evaluated through the assessment of spontaneously reported adverse experiences (AEs), evaluation of vital signs, and laboratory data reported by investigators and patients.

RESULTS

For the primary endpoint, reduction in pain at night over 6 weeks in Study 1 was not significantly different between active treatments; in Study 2 rofecoxib 25 mg significantly (p = 0.023) reduced pain at night compared with celecoxib 200 mg over 6 weeks. For the secondary endpoints, in both studies, significantly (p < 0.05) more patients treated with rofecoxib 25 mg than celecoxib 200 mg had a good or excellent PGART over 6 weeks, and over the first week (p < 0.01). In both studies, there were no significant differences between active medications in the incidence of reported overall, serious, or drug-related AEs. The reported AE rates with the active treatments were generally similar to those with placebo in the two studies.

CONCLUSIONS

Rofecoxib 25 mg was significantly better than celecoxib 200 mg in relieving night pain at 6 weeks in one study; this was not confirmed in the accompanying study.

COVALENT BINDING OF RADIOACTIVITY FROM [14C]ROFECOXIB, BUT NOT [14C]CELECOXIB OR [14C]CS-706, TO THE ARTERIAL ELASTIN OF RATS

Rofecoxib is a cyclooxygenase-2 (COX-2) inhibitor that has been withdrawn from the market because of an increased risk of cardiovascular (CV) events. With a special focus on the arteries, the distribution profiles of radioactivity in rats orally administered [14C]rofecoxib were investigated in comparison with two other COX-2 inhibitors, [14C]celecoxib and [14C]CS-706 (2-(4-ethoxyphenyl)-4-methyl 1-(4-sulfamoylphenyl)-1H-pyrrole), a novel selective COX-2 inhibitor. Whole-body autoradioluminography and quantitative determination of the tissue concentrations showed that considerable radioactivity is retained by and accumulated in the thoracic aorta of rats after oral administration of [14C]rofecoxib, but not [14C]celecoxib or [14C]CS-706. Acid, organic solvent, and proteolytic enzyme treatments of aorta retaining high levels of radioactivity from [14C]rofecoxib demonstrated that most of the radioactivity is covalently bound to elastin. In agreement with this result, the radioactivity was found to be highly localized on the elastic fibers in the aorta by microautoradiography. The retention of radioactivity on the elastic fibers was also observed in the aortic arch and the coronary artery. These findings indicate that [14C]rofecoxib and/or its metabolite(s) are covalently bound to elastin in the arteries. These data are consistent with the suggestion of modified arterial elasticity leading to an increased risk of CV events after long-term treatment with rofecoxib.

Cardiovascular risk with cyclooxygenase inhibitors: general problem with substance specific differences?

Randomised clinical trials and observational studies have shown an increased risk of myocardial infarction, stroke, hypertension and heart failure during treatment with cyclooxygenase inhibitors. Adverse cardiovascular effects occurred mainly, but not exclusively, in patients with concomitant risk factors. Cyclooxygenase inhibitors cause complex changes in renal, vascular and cardiac prostanoid profiles thereby increasing vascular resistance and fluid retention. The incidence of cardiovascular adverse events tends to increase with the daily dose and total exposure time. A comparison of individual selective and unselective cyclooxygenase inhibitors suggests substance-specific differences, which may depend on differences in pharmacokinetic parameters or inhibitory potency and may be contributed by prostaglandin-independent effects. Diagnostic markers such as N-terminal pro brain natriuretic peptide (NT-proBNP) or high-sensitive C-reactive protein might help in the early identification of patients at risk, thus avoiding the occurrence of serious cardiovascular toxicity.

Mechanisms of disease: Inflammatory mediators and cancer prevention

Discovery of molecular pathways critical to carcinogenesis is revolutionizing the treatment and prevention of cancer. Traditional chemotherapeutic approaches usually cause 'global' cytotoxicity to both normal and carcinoma cells. Over the past decade, however, investigators have developed compounds that inhibit tumor formation more selectively by targeting specific signaling pathways, including those involving the epidermal growth factor receptor (EGFR) and cyclooxygenase 2 (COX2). COX2-derived bioactive lipids, including prostaglandin E2, are potent inflammatory mediators that promote tumor growth and metastasis through stimulation of cell proliferation, invasion, and angiogenesis. Recent work has demonstrated significant crosstalk between the COX2 and EGFR pathways, while preclinical data demonstrates a synergistic effect when both pathways are targeted simultaneously. Combination therapy, a common strategy in cancer treatment, is likely to improve outcomes in cancer prevention as well. Ongoing clinical trials designed to assess whether low doses of COX2 and EGFR inhibitors used in combination could prove more effective and result in reduced toxicity than either agent alone may provide new options for cancer prevention and treatment. We discuss advances in cancer prevention by focusing on mechanisms by which bioactive lipids contribute to tumor formation. While cancer chemoprevention is a relatively young field, we argue that this approach to malignant disease bears significant potential.

Mechanisms for the prevention of gastrointestinal cancer: the role of prostaglandin E2

Carcinoma of the colon or rectum represents one of the most common malignancies worldwide with a higher prevalence in industrialized regions. Epidemiologic studies of individuals taking non-steroidal anti-inflammatory drugs (NSAIDs) have shown a significant reduction in colorectal cancer (CRC) mortality compared to those individuals not receiving these agents. NSAIDs inhibit the enzymatic activity of both isoforms of cyclooxygenase (COX-1 and COX-2), while COX-2-selective inhibitors have shown some efficacy in reducing polyp formation. COX-2-derived bioactive lipids, including the primary prostaglandin (PG) generated in colorectal tumors, PGE(2), are known to stimulate cell migration, proliferation and tumor-associated neovascularization while inhibiting cell death. Here we briefly review the role of NSAIDs in preventing CRC, as well as the proposed mechanism by which a COX-2-derived PG, PGE(2), promotes colon cancer.

COX-2 inhibitors and arterial hypertension: an analysis of spontaneous case reports in the Pharmacovigilance database

OBJECTIVE

To evaluate the main characteristics of case reports of arterial hypertension (AH) related to COX-2 inhibitor (coxib) use in real-life practice.

METHODS

This study was based on spontaneous reports of adverse drug reactions (ADRs) submitted to the French Pharmacovigilance system. Associations between AH and the different groups of those using non-steroidal anti-inflammatory drugs (NSAIDs: rofecoxib, celecoxib and non-selective NSAIDs) were compared using calculation of the odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

In France, between 1 April 2000 and 30 November 2003, 34 AH cases related to coxibs were reported. Case reports include predominantly patients older than 65 years, with a previous story of essential AH. Most AH (60%) occurred during the first 15 days of treatment. The AH was reported significantly more frequently for rofecoxib than celecoxib. The OR for development of AH with rofecoxib versus celecoxib was 3.3 (1.6-6.9). The AH was also reported more frequently with coxib (2.8%) than with non-selective NSAID (0.5%) use, OR = 5.9 (3.8-9.0).

CONCLUSION

This study shows that coxibs are associated with a risk of AH in real-life practice. More spontaneous reports of AH to the French Pharmacovigilance system concern rofecoxib than celecoxib (and coxibs than non-selective NSAIDs). This ADR is of special epidemiological importance due to both the risks of AH and the large use of coxibs.

Cyclo-oxygenase-2 inhibitors: when should they be used in the elderly?

Chronic pain in the elderly is frequently a result of arthritic disorders, particularly osteoarthritis. The cyclo-oxygenase (COX)-2 inhibitors are as effective as standard NSAIDs for the relief of pain and for improving function in elderly patients with osteoarthritis and rheumatoid arthritis. COX-2 inhibitors increase the risk of serious gastroduodenal adverse reactions but there is evidence that they carry a lower risk for these adverse effects than standard NSAIDs, except when there is concurrent aspirin use. Since gastroduodenal disorders are the most frequently reported serious adverse effects of NSAIDs and these disorders occur more frequently in the elderly, COX-2 inhibitors offer an alternative to standard NSAIDs in this age group. However, they are not appropriate for many patients with cardiovascular and renal disease. The adverse reaction profile of the COX-2 inhibitors has confirmed the role of the COX-2 enzyme in renal function, salt and water homeostasis and the vascular endothelium. Thus, like standard NSAIDs, COX-2 inhibitors can cause renal failure, hypertension and exacerbation of cardiac failure. Of note is that these disorders are dose related. Thus, there are good reasons to avoid high doses of COX-2 inhibitors in the elderly. Clinical trials indicate that daily doses of rofecoxib 12.5 mg, celecoxib 100-200 mg, valdecoxib 10mg and etoricoxib 60 mg are the minimum effective doses of these agents. Data from the New Zealand Intensive Medicines Monitoring Programme indicate that celecoxib 200 mg/day and rofecoxib 25 mg/day are/were the most commonly prescribed doses and that 6% of patients had taken rofecoxib 50 mg/day for longer than recommended. Recent research indicates that COX-2 inhibitors have a thrombotic potential, especially in high doses and when use is prolonged, and this further limits the extent to which they can be used in the elderly. Important interactions with COX-2 inhibitors in the elderly include those with warfarin, which can result in loss of control of anticoagulation, and those with ACE inhibitors, angiotensin II type 1 receptor antagonists and diuretics, which can result in loss of control of blood pressure and cardiac failure and, in hypovolaemic conditions, renal failure. The clinical significance of an interaction between celecoxib and aspirin to reduce the antiplatelet effect of the latter drug is unknown. Preliminary information from spontaneous reporting systems indicates that there may be differences in the risk of cardiac failure and hypertension between standard NSAIDs and COX-2 inhibitors and between rofecoxib and celecoxib. More formal studies using equivalent doses are needed to test this observation. Use of COX-2 inhibitors may be considered in the elderly to reduce the risk of gastroduodenal complications associated with standard NSAIDs but only when consideration has first been given to use of less toxic medicines as alternatives or supplements, the appropriate dose of the COX-2 inhibitor or standard NSAID, the presence and possible impact of co-morbidities, and the implications of taking COX-2 inhibitors with any concomitant medications. Equally important is regular monitoring of the patient taking a COX-2 inhibitor for efficacy and adverse effects, and ensuring that the patient has a continuing need to keep taking the drug. Close attention also needs to be paid to intercurrent illnesses and new prescriptions that may reduce the safety of the COX-2 inhibitor. A standard NSAID plus a proton pump inhibitor may be equally effective as a COX-2 inhibitor in reducing the risk of gastroduodenal toxicity and if used the same prescribing advice applies. Current knowledge concerning the thrombotic potential of COX-2 inhibitors suggests that this combination, if tolerated, may be preferable to a COX-2 inhibitor, particularly where prolonged use is required. This knowledge also indicates that for patients with or at high risk of ischaemic heart disease or stroke, COX-2 inhibitors are contraindicated.

Intracranial hypertension induced by rofecoxib

Several secondary causes are implicated in the etiology of idiopathic intracranial hypertension. Rofecoxib is a selective cyclo-oxygenase (COX)-2 inhibitor, now being increasingly used in place of nonselective nonsteroidal anti-inflammatory drugs (NSAIDs). We report a case of intracranial hypertension in a 69-year-old man 3 weeks after the commencement of rofecoxib therapy with reversal of clinical findings on drug withdrawal.

Blood Pressure in Native Americans Switched from Celecoxib to Rofecoxib

BACKGROUND:

Nonsteroidal antiinflammatory drugs have been associated with exacerbation of hypertension. Differing effects on blood pressure (BP) have been reported in studies comparing celecoxib and rofecoxib. Concern regarding the cardiovascular safety of the cyclooxygenase-2 (COX-2) inhibitor class has intensified since the removal of rofecoxib from the market.

OBJECTIVE:

To evaluate the effect of a formulary change from celecoxib to rofecoxib on the BP of Native American patients at an Indian Health Service medical center.

METHODS:

Medical records of patients switched from celecoxib to rofecoxib were retrospectively reviewed. BP during the respective treatments was compared as follows: measurements recorded while taking celecoxib within 6 months before the index date and while taking rofecoxib from 1 week after the index date through 6 months of treatment were averaged. Differences in systolic and diastolic BP before and after the therapy change were evaluated using a paired Student's t-test. Subgroup analysis was performed for patients with preexisting hypertension.

RESULTS:

During rofecoxib therapy, the mean systolic BP was 2.9 mm Hg higher (p = 0.015) and the mean diastolic BP was 1.5 mm Hg higher (p = 0.042) than during celecoxib therapy. Among hypertensive patients, the respective mean systolic and diastolic BPs were 4.8 mm Hg (p = 0.009) and 2.0 mm Hg (p = 0.063) higher while taking rofecoxib.

CONCLUSIONS:

Switching patients from celecoxib to rofecoxib resulted in an increase in BP, with a larger difference observed in patients with hypertension. Future studies assessing the cardiovascular safety of currently marketed and investigational COX-2 inhibitors should evaluate the possible contribution of BP effects of these agents to overall risk.

The role of prostaglandins and other eicosanoids in the gastrointestinal tract

Nonsteroidal anti-inflammatory drugs (NSAIDs) are generally prescribed to ameliorate symptoms associated with acute pain and chronic inflammatory diseases such as arthritis. Recent epidemiologic studies and clinical trials indicate that use of NSAIDs and cyclooxygenase (COX)-2 selective inhibitors are associated with a reduced risk of certain malignancies, especially gastrointestinal cancer. The cyclooxygenase enzymes are the best known targets of NSAIDs; this diverse class of compounds blocks conversion of arachidonic acid to prostanoids. Prostaglandins and other eicosanoids derived from COX-1 and COX-2 are involved in a variety of physiologic and pathologic processes in the gastrointestinal tract. Recent efforts to identify the molecular mechanisms by which COX-2-derived prostanoids exert their proneoplastic effects have provided a rationale for the possible use of NSAIDs alone or in a combination with conventional or experimental anticancer agents for the treatment or prevention of gastrointestinal cancers.