Combination of a cyclo-oxygenase-2 inhibitor and a proton-pump inhibitor for prevention of recurrent ulcer bleeding in patients at very high risk: a double-blind, randomised trial

BACKGROUND

Guidelines on pain management recommend that patients at risk of ulcers receive either a cyclo-oxygenase (COX 2) inhibitor or a non-steroidal anti-inflammatory drug (NSAID) with a proton-pump inhibitor (PPI). These two treatments have similar effectiveness, but they are insufficient for protection of patients at very high risk for ulcer bleeding. We aimed to test the hypothesis that in patients with previous ulcer bleeding induced by non-selective NSAIDs, combined treatment with the COX 2 inhibitor celecoxib and the PPI esomeprazole would be better than celecoxib alone for prevention of recurrent ulcer bleeding.

METHODS

441 consecutively presenting patients who were taking non-selective NSAIDs for arthritis were recruited to our single-centre, prospective, randomised, double-blind trial after admission to hospital with upper-gastrointestinal bleeding. Patients were enrolled after their ulcers had healed and a histological test for Helicobacter pylori was negative. All patients were given 200 mg celecoxib twice daily. 137 patients were randomly assigned to receive 20 mg esomeprazole twice daily (combined-treatment group), and 136 to receive a placebo (control group) for 12 months. The primary endpoint was recurrent ulcer bleeding during treatment or within 1 month of the end of treatment. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00365313.

FINDINGS

Combination treatment was more effective than celecoxib alone for prevention of ulcer bleeding in patients at high risk. The 13-month cumulative incidence of the primary endpoint was 0% in the combined-treatment group and 12 (8.9%) in the controls (95% CI difference, 4.1 to 13.7; p=0.0004). The median follow-up was 13 months (range 0.4-13.0). Discontinuation of treatment and the incidence of adverse events were similar in the two treatment groups.

INTERPRETATION

Patients at very high risk for recurrent ulcer bleeding who need anti-inflammatory analgesics should receive combination treatment with a COX 2 inhibitor and a PPI. Our findings should encourage guideline committees to review their recommendations for patients at very high risk of recurrent ulcer bleeding.

Anti-inflammatory and side effects of cyclooxygenase inhibitors

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly used drugs in inflammatory diseases, since they are effective in management of pain, fever, redness, edema arising as a consequence of inflammatory mediator release. Studies have shown that both therapeutic and side effects of NSAIDs are dependent on cyclooxygenase (COX) inhibition. COX isoforms have been named constitutive (COX-1) and inducible (COX-2). COX-1 catalyzes formation of cytoprotective prostaglandins in thrombocytes, vascular endothelium, stomach mucosa, kidneys, pancreas, Langerhans islets, seminal vesicles, and brain. Induction of COX-2 by various growth factors, proinflammatory agents, endotoxins, mitogens, and tumor agents indicates that this isoform may have a role in induction of pathological processes, such as inflammation. It is well known that therapy with COX inhibitors is associated with a number of side effects including gastrointestinal erosions, and renal and hepatic insufficiency. Such critical adverse reactions are mostly dependent on COX-1 inhibition. As a result of research focused on reduction of the adverse effects of NSAIDs, selective COX-2 inhibitors, such as celecoxib and rofecoxib have been developed. However, many data demonstrate that mechanisms of action of these drugs are multidirectional and complex. These drugs or their derivatives, which belong to the same group, have distinct pharmacological effects, side effects and potencies which implies that there may be more than two, five or even tens of COX isoforms.

Combining enzyme specificity and tissue selectivity of cyclooxygenase inhibitors: towards better tolerability?

Inhibitors of cyclooxygenases (COXs) are the most widely used drugs. They reduce discomfort and fever, inhibit peri-operative and inflammatory pain. These effects are largely mediated by inhibition of cyclooxygenase-1 and -2 (COX-1 and COX-2)-enzymes found throughout the body producing prostaglandins, which are important mediators of pain and fever, but also adaptive and protective reactions in many organs. A first step to reduce the overall toxicity and to increase the anti-inflammatory activity of these drugs was achieved with the development of acidic 'non-selective' (traditional) non-steroidal anti-inflammatory drugs (tNSAIDs). These agents distribute unequally throughout the body, reaching effective concentrations in inflamed tissue (effect compartment) for prolonged time periods. They can also reach effective concentrations in the bloodstream, kidney and gastrointestinal (GI) mucosa, where they can cause unwanted effects, such as GI toxicity, kidney dysfunction and cardiovascular impairment. All these effects are particularly prominent with compounds which are eliminated slowly [half-life (T((1/2))) >12 h] and thus also block prostaglandin production permanently outside the effect compartment. A second step towards improving safety was achieved with selective COX-2 inhibitors. These agents reduce the incidence of GI toxicity, pseudo-asthmatic reactions and blood loss following surgical interventions. However, they may be more toxic to the cardiovascular and renal systems than some tNSAIDs, possibly because they distribute homogeneously throughout the body and inhibit COX-2 in the endothelial layer of the vessels and the kidney permanently due to their slow elimination. Another step towards improvement in safety appears possible by combining both enzyme specificity and tissue selectivity, to achieve a further reduction of unwanted drug effects while maintaining the anti-inflammatory/analgesic efficacy.

Naproxen and celecoxib do not prevent AD in early results from a randomized controlled trial

OBJECTIVE

To evaluate the efficacy and safety of naproxen and celecoxib for the primary prevention of Alzheimer disease (AD).

METHODS

Randomized, placebo-controlled, double-masked clinical trial conducted at six US dementia research clinics. Volunteers aged 70+ years, with cognitive screening scores above designated cut-offs and a family history of AD, were randomly assigned to celecoxib 200 mg BID, naproxen sodium 220 mg BID, or placebo. Enrollment began in early 2001. The main outcome measure was diagnosis of AD after randomization.

RESULTS

On December 17, 2004, treatments were suspended. Events while on treatment yielded hazard ratios vs placebo of 1.99 (95% CI 0.80 to 4.97; p = 0.14) for celecoxib and 2.35 (0.95 to 5.77; p = 0.06) for naproxen. Imperfect screening measures led to enrollment of 7 individuals with dementia and 46 others with milder cognitive syndromes. Their (prevalent) illness was detected at enrollment and diagnosed within 6 months following randomization. Secondary analyses that excluded the 7 cases of prevalent dementia showed increased hazard ratios for AD with both treatments. Neither treatment produced a notable effect on the incidence of milder cognitive syndromes.

CONCLUSIONS

These results do not support the hypothesis that celecoxib or naproxen prevent Alzheimer dementia, at least within the early years after initiation of treatment. Masked long-term follow-up of these participants will be essential.

COX-2 inhibition: a possible role in the management of prostate cancer?

There is mounting evidence to support a role for cyclooxygenase-2 (COX-2) inhibitors (coxibs) in the management of prostate cancer. This review considers the current evidence base for the use of coxibs in prostate cancer as well as their adverse event profile. A systematic literature review using the search terms 'cyclooxygenase', 'COX-2', 'coxibs', 'cardiovascular risk', and 'prostate cancer' was performed using Medline. Celecoxib appears safer in terms of cardiovascular toxicity than other coxibs, and this may relate to its lower selectivity for the COX-2 enzyme. This lower selectivity also provides rationale for its putative broader anti-cancer effects, via non-COX-2-dependent pathways that affect cell cycle regulation, angiogenesis, and hypoxic modulation. There are also interacting relationships between COX-2, chronic inflammation, and prostate cancer. There is much promise for the coxibs as anti-cancer agents. The future might be to pharmacologically adapt these agents to exert their COX-2 independent mechanisms of action while minimizing their COX-2-dependent adverse cardiovascular effects.

Thromboembolic cardiovascular risk among arthritis patients using cyclooxygenase-2-selective inhibitor or nonselective cyclooxygenase inhibitor nonsteroidal anti-inflammatory drugs

Selective cyclooxygenase (COX)-2 inhibitors have been associated with an increased risk of thromboembolic cardiovascular (CV) events. Prior studies have found that rofecoxib has a destabilizing effect on blood pressure; however, whether this translates to an increased risk of thromboembolic CV events is unknown. The objective of this study was to evaluate risk of thromboembolic CV events among hypertensive and nonhypertensive patients treated with rofecoxib or celecoxib, nonselective nonsteroidal anti-inflammatory drugs (ns-NSAIDs), or no NSAIDs (nonusers). This was a retrospective cohort study of 31,743 adult arthritis patients enrolled in a Blue Cross/Blue Shield health insurance plan in the northeastern United States. The main outcome measure was incident acute myocardial infarction and stroke. A clinically significant channeling effect was observed where selective COX-2 inhibitor users had a more severe CV risk profile. Among normotensive patients, the hazard ratio (HR) of CV events for ns-NSAIDs, rofecoxib, or celecoxib versus nonusers was 0.91 (95% confidence interval, 0.68-1.21), 1.05 (0.61-1.80), and 1.19 (0.86-1.66), respectively. Among hypertensive patients, the risk of CV events for ns-NSAIDs users was not significantly different versus nonusers (HR=1.21; 0.88-1.67). However, rofecoxib was associated with a significant 2-fold increase in CV risk versus nonusers of NSAIDs (HR=2.16; 1.51-3.09), whereas celecoxib was not (HR=1.18; 0.89-1.57). These data support the hypothesis that elevated CV risk is not a drug class effect of selective COX-2 inhibitors. That this effect was specific to hypertensive patients indicates that blood pressure destabilization is likely an important contributing mechanism.

[A novel class of anti-inflammatory and analgesic drugs--NO-donating NSAIDs]

Traditional non-steroidal anti-inflammatory drugs (NSAIDs) and COX-2 selective inhibitors are among the most widely used drugs. However, their significant side effects in gastrointestinal and cardiovascular systems limited the use of these drugs. Recently, research and development of NO-donating NSAIDs (NO-NSAIDs) have become one of the most important strategies to reduce these side effects. NO-NSAIDs may exert a broad range of positive effects in terms of NO-mediated gastrointestinal and cardiovascular safety as well as comparable or increased anti-inflammatory, analgesic properties relative to NSAIDs. This review briefly deals with chemistry of NO-NSAIDs, more details are focused on biological significance, mechanism of action, and therapeutic potential of this novel class of drugs.

Oral and intravenous administration of nimesulide in the horse: rational dosage regimen from pharmacokinetic and pharmacodynamic data

REASONS FOR PERFORMING STUDY

The selective COX-2-inhibitor nimesulide is used extra-label in equine veterinary practice as an anti-inflammatory agent. However, there are no data on which to base the rational use of the drug in this species.

OBJECTIVES

To determine the effective COX selectivity of nimesulide in the horse, and suggest a suitable dosing schedule.

METHODS

The pharmacokinetics of nimesulide in the horse after oral administration (1 mg/kg bwt), and oral and i.v. administration (1.5 mg/kg bwt) were investigated, effects of feeding status on bioavailability determined, and plasma protein binding of the drug and its principal metabolites measured. Compartmental and noncompartmental pharmacokinetic analyses were performed. The plasma concentration-time profile was used, together with in vitro literature data on nimesulide inhibition of COX isoforms, to determine the effective COX selectivity of nimesulide in the horse, and suggest a suitable dosing schedule.

RESULTS AND CONCLUSIONS

The findings suggest that 1.5 mg/kg bwt may produce adequate clinical effects, and the dosing interval should be 12-24 h depending on condition severity. However, at that dose, the concentration in the animal exceeds the in vitro IC50 for both isoforms, so that COX-1/COX-2 selectivity is lost and side-effects due to COX-1 inhibition are a possibility. Nimesulide should therefore be used with caution in equine clinical practice.

[Prenatal tolerability evaluation of diclofenac]

Diclofenac is a nonsteroidal anti-inflammatory drug that nonselectively inhibits constitutive and inducible isoenzymes of cyclooxygenase. It's a potent anti-inflammatory, analgesic and antipyretic agent that recently belong to the over-the-counter drugs. Several animal studies on reproductive effect of diclofenac have been conducted. The overall results do not implicate the drug teratogenicity. However, intrauterine growth retardation, constriction of ductus arteriosus, fetal anuria, oligohydramnions and other prostanoid-related side-effects were already reported. On the other hand, data from human reports do not support opinion about the connection between diclofenac exposure and the potential risk to the fetus.

Cost analysis applied to postoperative analgesia regimens: a comparison between parecoxib and propacetamol

BACKGROUND

Postoperative pain management represents a significant part of perioperative costs. Non-opioid analgesics are often used in combination with opiates to improve pain relief and reduce opioid-related side effects.

OBJECTIVE

To assess the costs and cost efficacy of intravenous (i.v.) parecoxib versus i.v. propacetamol in postoperative pain.

METHODS

A prospective, randomised, double-blind, clinical evaluation was performed to compare the efficacy of a single bolus injection of 40 mg parecoxib and 2 g propacetamol, administered twice within 12 h following surgical repair of inguinal hernia. Resources for each arm of treatment were collected, and total costs were determined, including costs of drug acquisition, devices and labour for preparation of the two analgesic drugs. Cost-efficacy analysis was performed as the cost to achieve complete satisfaction with analgesia. Incremental cost efficacy was determined as the ratio between the differential costs and the differential patient satisfaction. The analysis was performed from an institutional perspective over a 12 h time frame.

RESULTS

A total of 182 patients was evaluated. Pain at rest and morphine consumption were observed to be reduced in the parecoxib group. The percentages of patients totally satisfied with their pain management 12 h after surgery were 87% in the parecoxib-treated group and 70% in the propacetamol-treated group (P < 0.01). The average cost per patient was higher in the parecoxib group, 6.65 euros vs 5.28 euros in the propacetamol group). Cost per patient satisfied was calculated at a mean value of 7.64 euros for parecoxib and 7.54 euros for propacetamol. Incremental cost per additional patient satisfied was 8.02 euros in the parecoxib-treated group when preparation costs were included. Sensitivity analysis (+/-15%), including a bootstrap method applied to costs and efficacy, did not modify these conclusions.

CONCLUSION

Parecoxib exhibits higher cost and greater patient satisfaction than does propacetamol. From a cost-efficacy approach, incremental cost per additional patient satisfied for parecoxib treatment must be analysed in light of overall perioperative pharmaceutical cost.

Assessment of upper gastrointestinal safety of etoricoxib and diclofenac in patients with osteoarthritis and rheumatoid arthritis in the Multinational Etoricoxib and Diclofenac Arthritis Long-term (MEDAL) programme: a randomised comparison

BACKGROUND

Upper gastrointestinal safety of cyclo-oxygenase (COX)-2 selective inhibitors versus traditional non-steroidal anti-inflammatory drugs (NSAIDs) has not been assessed in trials that simulate standard clinical practice. Our aim was to assess the effects of these drugs on gastrointestinal outcomes in a population that includes patients taking gastrointestinal protective therapy.

METHODS

A prespecified pooled intent-to-treat analysis of three double-blind randomised comparisons of etoricoxib (60 or 90 mg daily) and diclofenac (150 mg daily) in 34 701 patients with osteoarthritis or rheumatoid arthritis was done for upper gastrointestinal clinical events (bleeding, perforation, obstruction, or ulcer) and the subset of complicated events (perforation, obstruction, witnessed ulcer bleeding, or significant bleeding). We also assessed such outcomes in patients who were taking concomitant proton pump inhibitors (PPIs) or low-dose aspirin. These trials are registered with , with the numbers , , and .

FINDINGS

Overall upper gastrointestinal clinical events were significantly less common with etoricoxib than with diclofenac (hazard ratio [HR] 0.69, 95% CI 0.57-0.83; p=0.0001). There were significantly fewer uncomplicated gastrointestinal events with etoricoxib than there were with diclofenac (0.57, 0.45-0.74; p<0.0001); there was no difference in complicated events (0.91, 0.67-1.24; p=0.561). PPIs were used concomitantly for at least 75% of the study period by 13 862 (40%) and low-dose aspirin by 11 418 (33%) patients; treatment effects did not differ significantly in these individuals.

INTERPRETATION

There were significantly fewer upper gastrointestinal clinical events with the COX-2 selective inhibitor etoricoxib than with the traditional NSAID diclofenac due to a decrease in uncomplicated events, but not in the more serious complicated events. The reduction in uncomplicated events with etoricoxib is maintained in patients treated with PPIs and is also observed with regular low-dose aspirin use.

Tolerability to nabumetone and meloxicam in patients with nonsteroidal anti-inflammatory drug intolerance

BACKGROUND

Because nonsteroidal anti-inflammatory drug (NSAID) intolerance depends on COX-1 inhibition, preferential or selective COX-2 inhibitors have been thought to be well tolerated by these patients.

OBJECTIVE

The aim of this study is to evaluate tolerability to nabumetone and meloxicam in patients with NSAID intolerance.

METHODS

Seventy patients intolerant to NSAIDs were selected. Thirty subjects were patients with asthma with respiratory (rhinitis-asthma) intolerance to NSAIDs (group A); 40 patients (group B) had cutaneous-mucous (urticaria-angioedema) NSAID intolerance. Diagnosis was based on clinical histories in all patients, and it was confirmed by positive single-blind placebo-controlled oral challenge test in 36 patients. After written informed consent, a single-blind placebo-controlled oral challenge test with nabumetone in all patients (2 g except for 11 patients who reached 1 g) and meloxicam (15 mg) in 51 patients was performed.

RESULTS

Of the total selected, 94.3% tolerated 1 g nabumetone. In those who reached the 2-g dose, the tolerability was 83.6%. With respect to meloxicam, 96.1% of patients, tolerated 15 mg. No significant difference in nabumetone and meloxicam tolerability was observed between groups A and B.

CONCLUSION

The results of this study confirm a high percentage of tolerability to the maximum therapeutic dosage of nabumetone and meloxicam in patients with NSAID intolerance, both in those with cutaneous/mucous manifestations and in those with respiratory disease.

CLINICAL IMPLICATIONS

Nabumetone and meloxicam are safe alternatives in NSAID-intolerant patients.

A randomized, double-blind, one-week study comparing effects of a novel COX-2 inhibitor and naproxen on the gastric mucosa

CS-706 is a novel cyclooxygenase-2 (COX-2) inhibitor with potent analgesic, anti-inflammatory, and antitumor properties in animal models. This one-week, multicenter study was undertaken to assess the safety and tolerability of CS-706 and to compare the effects of CS-706 versus naproxen on acute gastrointestinal (GI) mucosal injury. Healthy men and women (n=160) without evidence of underlying gastroduodenal lesions were randomized to placebo, 100 mg CS-706 once daily, 200 mg CS-706 once daily, or 500 mg naproxen twice daily, administered for 7 days. On Day 8, subjects underwent a posttreatment upper GI endoscopy to assess development of gastroduodenal petechiae, erosions, and ulcers. Inhibition of COX-1 and COX-2 activity over the 24-hr postdose interval on Day 7 was determined in 48 subjects (12 per treatment group). CS-706 was safe and well tolerated. The extent of upper GI mucosal injury for both CS-706 dose groups was statistically significantly less than that for naproxen (P < 0.001) and was similar to placebo (P=0.615 and P=0.115 for 100 and 200 mg CS-706, respectively). No subject in placebo or either CS-706 treatment group had gastroduodenal ulcers, compared with 11 (28.2%) subjects treated with naproxen (P < 0.001). Both doses of CS-706 inhibited COX-2 activity to a similar extent as naproxen, whereas neither dose of CS-706 showed meaningful inhibition of platelet COX-1. In contrast, naproxen nearly completely inhibited COX-1 over the dosing interval. We conclude that CS-706, dosed up to 200 mg once daily, has an acute, upper GI toxicity profile similar to that of placebo and significantly superior to that of naproxen.

Preconditioning stress prevents cold restraint stress-induced gastric lesions in rats: roles of COX-1, COX-2, and PLA2

We investigated the protective effect of mild stress on gastric lesions induced by cold-restraint stress, especially concerning prostaglandins (PGs)/cyclo-oxygenase (COX) isozymes. Rats were exposed to severe stress (cold-restraint stress at 10 degrees C for 6 hr) or mild stress (cold-restraint stress at 10 degrees C for 30 min and kept at room temperature for 60 min) followed by severe stress. Severe stress induced gastric lesions, with a concomitant decrease in body temperature (BT). The ulcerogenic response was inhibited by atropine but worsened by indomethacin and SC-560 but not rofecoxib, although none of these agents had any effect on the change in BT. Mild stress suppressed the gastric ulceration and the decrease in BT induced by severe stress, and these effects were reversed by both COX-1 and COX-2 inhibitors. The expression of COX-2 in the stomach was up-regulated from 4 hr after severe stress and this response was slightly expedited by mild stress. COX-2 was also expressed in the hypothalamus under normal and stressed conditions. Quinacrine (phospholipase A(2) inhibitor) attenuated the protective effect of mild stress on the ulceration and decrease in BT caused by severe stress. TA-0910 (TRH analogue) at a low dose also prevented the gastric ulceration and the decrease in BT induced by severe stress. These results suggest that mild stress protects against cold-restraint stress-induced gastric ulceration, and the effect is peripherally and centrally mediated by PGs derived from both COX-1 and COX-2 through the activation of phospholipase A(2). TRH may also be involved in the protective effect of mild stress, probably through regulation of the thermogenic system.

Choosing nonselective NSAIDs and selective COX-2 inhibitors in the elderly. A clinical use pathway

The literature has well established that nonsteroidal anti-inflammatory drugs (NSAIDS) are very effective in treating pain and inflammation, but these drugs are associated with significant gastrointestinal (GI) toxicity. This is especially true in the elderly patient population. Selective cyclooxygenase-2 (COX-2) inhibitors (coxibs) were developed to decrease the incidence of GI adverse events. Nevertheless, recent concerns regarding coxibs and their association with adverse cardiovascular events have led physicians to re-examine the appropriate use of all NSAIDs. Part 1 of this two-part article reviews essential data related to adverse GI events to help physicians select appropriate patients to receive nonselective NSAIDs or coxibs. Other considerations, such as the benefits of proton pump inhibitors (PPIs) and the mitigating effects of concurrent aspirin use, are also discussed. Our clinical use pathway or algorithm will frame the discussion and guide clinicians through what has become a difficult decision in daily practice.

Gastrointestinal side effects of etoricoxib in patients with osteoarthritis: results of the Etoricoxib versus Diclofenac Sodium Gastrointestinal Tolerability and Effectiveness (EDGE) trial

OBJECTIVE

. To compare the gastrointestinal (GI) tolerability, safety, and efficacy of etoricoxib and diclofenac in patients with osteoarthritis (OA).

METHODS

In total, 7111 patients (mean age 64 yrs) diagnosed with OA were enrolled in a randomized, double-blind trial. Patients received etoricoxib 90 mg qd (n = 3593) or diclofenac sodium 50 mg tid (n = 3518). Gastroprotective agents and low-dose aspirin were prescribed per treatment guidelines. The primary endpoint was the cumulative rate of discontinuations due to clinical and laboratory GI adverse experiences (AE). General safety was assessed, including adjudication of thrombotic cardiovascular (CV) safety data. Efficacy was evaluated using the least-square (LS) mean change from baseline patient global assessment of disease status (PGADS; 0-4 point scale).

RESULTS

Mean (SD, maximum) duration of treatment was 9.3 (4.4, 16.5) and 8.9 (4.5, 16.6) months in the etoricoxib and diclofenac groups, respectively. The cumulative discontinuation rate due to GI AE was significantly lower with etoricoxib than diclofenac [9.4 vs 19.2 events per 100 patient-years (PY), respectively; hazard ratio (HR) 0.50 (95% CI 0.43, 0.58; p < 0.001). Rates of thrombotic CV events were similar with etoricoxib and diclofenac [1.25 vs 1.15 events per 100 PY, respectively; HR 1.07 (95% CI 0.65, 1.74)]. The incidence of patients who discontinued due to hypertension-related AE was significantly higher with etoricoxib compared to diclofenac (2.3% vs 0.7%; p < 0.001), although few AE were severe (3 etoricoxib, 1 diclofenac). Etoricoxib and diclofenac treatment resulted in similar improvements in PGADS from baseline of -0.78 (95% CI -0.80, -0.75) and -0.75 (95% CI -0.77, -0.72), respectively.

CONCLUSION

Treatment with etoricoxib 90 mg was associated with significantly better GI tolerability compared to diclofenac in this population of patients with OA. Etoricoxib 90 mg, a dose 50% higher than indicated for OA, resulted in more discontinuations due to hypertension-related AE.

Nitroflurbiprofen, a nitric oxide-releasing cyclooxygenase inhibitor, improves cirrhotic portal hypertension in rats

BACKGROUND & AIMS

We studied whether administration of nitroflurbiprofen (HCT-1026), a cyclooxygenase inhibitor with nitric oxide (NO)-donating properties, modulates the increased intrahepatic vascular tone in portal hypertensive cirrhotic rats.

METHODS

In vivo hemodynamic measurements (n = 8/condition) and evaluation of the increased intrahepatic resistance by in situ perfusion (n = 5/condition) were performed in rats with thioacetamide-induced cirrhosis that received either nitroflurbiprofen (45 mg/kg), flurbiprofen (30 mg/kg, equimolar concentration to nitroflurbiprofen), or vehicle by intraperitoneal injection 24 hours and 1 hour prior to the measurements. Additionally, we evaluated the effect of acute administration of both drugs (250 micromol/L) on the intrahepatic vascular tone in the in situ perfused cirrhotic rat liver (endothelial dysfunction and hyperresponsiveness to methoxamine) and on hepatic stellate cell contraction in vitro. Typical systemic adverse effects of nonsteroidal anti-inflammatory drugs, such as gastrointestinal ulceration, renal insufficiency, and hepatotoxicity, were actively explored.

RESULTS

In vivo, nitroflurbiprofen and flurbiprofen equally decreased portal pressure (8 +/- 0.8 and 8.4 +/- 0.1 mm Hg, respectively, vs 11.8 +/- 0.6 mm Hg) and reduced the total intrahepatic vascular resistance. Systemic hypotension was not aggravated in the different treatment groups (P = .291). In the perfused cirrhotic liver, both drugs improved endothelial dysfunction and hyperresponsiveness. This was associated with a decreased hepatic thromboxane A(2)-production and an increased intrahepatic nitrate/nitrite level. In vitro, nitroflurbiprofen, more than flurbiprofen, decreased hepatic stellate cells contraction. Flurbiprofen-treated rats showed severe gastrointestinal ulcerations (bleeding in 3/8 rats) and nefrotoxicity, which was not observed in nitroflurbiprofen-treated cirrhotic rats.

CONCLUSIONS

Treatment with nitroflurbiprofen, an NO-releasing cyclooxygenase inhibitor, improves portal hypertension without major adverse effects in thioacetamide-induced cirrhotic rats by attenuating intrahepatic vascular resistance, endothelial dysfunction, and hepatic hyperreactivity to vasoconstrictors.

Cyclooxygenase-2 Inhibition Increases Mortality, Enhances Left Ventricular Remodeling, and Impairs Systolic Function After Myocardial Infarction in the Pig

BACKGROUND

Cyclooxygenase (COX)-2 expression in the heart increases after myocardial infarction (MI). In murine models of MI, COX-2 inhibition preserves left ventricular dimensions and function. We studied the effect of selective COX-2 inhibition on left ventricular remodeling and function after MI in a pig model.

METHODS AND RESULTS

Twenty-two pigs were assigned to COX-2 inhibition with a COX-2 inhibitor (COX-2i; celecoxib 400 mg twice daily; n=14) or a control group (n=8). MI was induced by left circumflex coronary artery ligation, and the animals were euthanized 6 weeks later. Cardiac dimensions and function were assessed with echocardiography and conductance catheters. Infarct size and collagen density were analyzed with triphenyltetrazolium chloride staining and picrosirius red staining, respectively. COX-2 inhibition increased mortality compared with controls (50% versus 0%, P=0.022), whereas infarct size was similar (13.1+/-0.7% versus 14.1+/-0.1%, P=0.536). The decrease in thickness of the infarcted myocardial wall was more pronounced in the COX-2i group (60.6+/-9.6% versus 36.2+/-5.7%, P=0.001). End-diastolic volume was higher in the COX-2i group (133.9+/-33.5 versus 91.1+/-24.0 mL; P=0.021), as was the end-systolic volume at 100 mm Hg (81.7+/-27.8 versus 56.3+/-21.1 mL; P=0.037), which indicates that systolic function was more severely impaired. Infarct collagen density was lower after COX-2i treatment (25.3+/-3.9 versus 56.1+/-23.8 gray value/mm2; P=0.005).

CONCLUSIONS

In pigs, COX-2 inhibition after MI is associated with increased mortality, enhanced left ventricular remodeling, and impaired systolic function, probably due to decreased infarct collagen fiber density.

Comparison of etoricoxib and indomethacin for the treatment of experimental periodontitis in rats

We investigated the effect of etoricoxib, a selective cyclooxygenase-2 inhibitor, and indomethacin, a non-selective cyclooxygenase inhibitor, on experimental periodontitis, and compared their gastrointestinal side effects. A ligature was placed around the second upper left molars of female Wistar rats (160 to 200 g). Animals (6 per group) were treated daily with oral doses of 3 or 9 mg/kg etoricoxib, 5 mg/kg indomethacin, or 0.2 mL saline, starting 5 days after the induction of periodontitis, when bone resorption was detected, until the sacrifice on the 11th day. The weight and survival rate were monitored. Alveolar bone loss (ABL) was measured as the sum of distances between the cusp tips and the alveolar bone. The gastric mucosa was examined macroscopically and the periodontium and gastric and intestinal mucosa were examined by histopathology. The ongoing ABL was significantly inhibited (P < 0.05) by 3 and 9 mg/kg etoricoxib and by indomethacin: control = 4.08 +/- 0.47 mm; etoricoxib (3 mg/kg) = 1.89 +/- 0.26 mm; etoricoxib (9 mg/kg) = 1.02 +/- 0.14 mm; indomethacin = 0.64 +/- 0.15 mm. Histopathology of periodontium showed that etoricoxib and indomethacin reduced inflammatory cell infiltration, ABL, and cementum and collagen fiber destruction. Macroscopic and histopathological analysis of gastric and intestinal mucosa demonstrated that etoricoxib induces less damage than indomethacin. Animals that received indomethacin presented weight loss starting on the 7th day, and higher mortality rate (58.3%) compared to etoricoxib (0%). Treatment with etoricoxib, even starting when ABL is detected, reduces inflammation and cementum and bone resorption, with fewer gastrointestinal side effects.

Use of nonsteroidal antiinflammatory drugs in dental practice. A review

Nonsteroidal antiinflammatory drugs (NSAIDs) are drugs commonly prescribed in dental practice for the management of pain and swelling. Of these substances, paracetamol and ibuprofen are the most widely used. Their mechanism of action is based on the inhibition of cyclooxygenase, and therefore of prostaglandin synthesis. All of these drugs present a similar mechanism of action, as a result of which their side effects are also similar. The most frequent range from mild (e.g., nausea or vomiting) to serious gastric problems (such as gastric bleeding or perforation). Other side effects include an increased risk of vascular accidents (particularly acute myocardial infarction), renal toxicity secondary to a decrease in perfusion, and the risk of abnormal bleeding tendency due to the antiplatelet effect of these drugs. Their use is contraindicated in the third trimester of pregnancy, due to the induction of premature ductus arteriosus closure. The present study reviews the information currently available on NSAIDs, with special emphasis on those aspects related to dental practice.

Risk of cardiovascular events in patients receiving celecoxib: a meta-analysis of randomized clinical trials

Some nonsteroidal anti-inflammatory drugs (NSAIDs), including cyclooxygenase-2 selective inhibitors, have been associated with increased cardiovascular (CV) events in recent clinical trials or observational studies. To determine whether the cyclooxygenase-2 selective inhibitor celecoxib affects CV risk, the incidence of CV events was analyzed in patients treated with celecoxib, placebo, or nonselective NSAIDs in the clinical trial database for celecoxib using defined Antiplatelet Trialists' Collaboration end points of nonfatal myocardial infarction, nonfatal stroke, and CV death. Patient data were derived from studies in osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, low back pain, and Alzheimer's disease. This meta-analysis included (1) 7,462 patients exposed to celecoxib 200 to 800 mg/day for 1,268 patient-years compared with 4,057 patients treated with placebo for 585 patient-years, and (2) 19,773 patients treated with celecoxib 200 to 800 mg/day for 5,651 patient-years compared with 13,990 patients treated with nonselective NSAIDs (diclofenac, ibuprofen, naproxen, ketoprofen, and loxoprofen) for 4,386 patient-years. CV events were adjudicated by a 3-member expert end point committee (WBW, JSB, PBG) blinded to treatment group and study. The incidence rates of the combined CV events were not significantly different between patients treated with celecoxib and placebo or between those treated with celecoxib and nonselective NSAIDs. Event rates were similar for adjudicated and nonadjudicated data. Dose of celecoxib, the use of aspirin, or the presence of CV risk factors did not alter these results. In conclusion, these analyses failed to demonstrate an increased CV risk with celecoxib relative to placebo and demonstrated a comparable rate of CV events with celecoxib treatment compared with nonselective NSAIDs.

Lumiracoxib

Lumiracoxib is a selective cyclooxygenase (COX)-2 inhibitor that possesses a carboxylic acid group that makes it weakly acidic. It has good oral bioavailability; maximum plasma concentrations are reached two hours after oral administration. Despite its short elimination half-life of four hours from the plasma, the drug is distributed to inflamed tissues and is retained for up to 24 hours. This unique property suggests that lumiracoxib, while having reduced systemic exposure, can still reach sites where COX-2 inhibition is required for pain relief. Lumiracoxib is metabolized extensively with only a small amount excreted in the urine. Selectivity for COX-2 is high compared to all other similar agents. It is indicated for the relief of pain in osteoarthritis, rheumatoid arthritis, acute pain and primary dysmenorrhea. Lumiracoxib has been found to be effective at doses of 100-400 mg once a day for chronic pain and 400 mg/day for acute pain. Large clinical trials where lumiracoxib was administered to patients with osteoarthritis have demonstrated that this drug is equally effective as other COX-2 inhibitors and nonsteroidal anti-inflammatory drugs (NSAIDs). In comparison to NSAIDs, patients taking lumiracoxib experience significantly fewer adverse events and greater tolerability. It has also been shown to be effective in acute pain states, like the dental pain model and postoperative pain after orthopedic surgery. A large clinical study (TARGET) has demonstrated the gastrointestinal safety of lumiracoxib over one year. The study also showed that there was no increase in cardiovascular events in non-high-risk patients. However, a black box warning similar to those accompanying other COX-2 inhibitors has been placed by regulatory agencies that have approved this drug for clinical use. When lumiracoxib is coadministered with warfarin or aspirin, no dosage adjustment is required.

Usefulness of indomethacin for patent ductus arteriosus in full-term infants

The aim of this retrospective study was to evaluate the effectiveness of indomethacin therapy for patent ductus arteriosus (PDA) in full-term infants. The patients were 41 full-term infants with a PDA birth weight (BW) > or =2500 g and a gestational age (GA) > or =37 weeks. The echocardiographic evaluation and medical management of PDA in these infants was similar to that for PDA in low-birth-weight infants. Indomethacin (0.2-0.25 mg/kg/dose) was given intravenously at 12-24-hour intervals within 23 days of birth. Of the 41 infants, 12 showed complete closure, and 13 showed improvement of clinical symptoms. These 25 infants were classified as the responder group (61%). The other 16 infants, who did not show improvement in clinical symptoms, were classified as the nonresponder group. Statistical analysis revealed no difference between the two groups regarding GA, BW, Apgar score at 1 minute, minimum diameter of the DA before treatment, the average age at the initiation of treatment, and DA flow pattern. No severe adverse reactions were observed in any infant. Indomethacin therapy appears to be an effective medical treatment option for PDA in full-term symptomatic infants prior to considering surgical treatment.

[Immunological aspects of postoperative analgesia after abdominal hysterectomy]

BACKGROUND

Prostaglandins modulate cytokine release though increases in cAMP, regulating interleukin-6 and interleukin-10. Ketoprofen inhibits cyclo-oxygenase activity and hence prostaglandin production.

AIM

We hypothesized that ketoprofen would affect release of IL-6 and IL-10 and modulate the immune response.

METHOD

We have evaluated 40 women, divided into four groups by the model of postoperative pain treatment: control group (only opioid) and experimental group (combination of i.v. ketoprofen and opioid). Serum IL-6 and IL-10 were measured before surgery, 24 and 72 hours after skin incision. Due to days in hospital we detected temperature and severe complications.

RESULTS

IL-6 increased at 24h and normalized at 72h. In contrast IL-10 did not change significantly.

CONCLUSION

The two models of postoperative analgesia have both modulated immune response after abdominal hysterectomy in same way.

[Non-steroidal anti-inflammatory drugs and intestinal side effects]

Non-steroidal anti-inflammatory drugs (NSAID), including acetylsalicylic acid, are the most commonly applied in the world, however at the same time they constitute a risk factor for gastrointestinal complications. The main mechanism of action of NSAID is based on reducing the synthesis of prostaglandins by means of inhibiting the activity of cyclooxygenase (COX), namely, of COX-1, which generates gut protective prostaglandins, and COX-2, induced at the sites of inflammation, tissue lesions and certain neoplasm. Complications caused by NSAID within the upper gut are subject to numerous studies; however those affecting the intestines are considerably less known. The complications accompanying the use of NSAID may include intestinal strictures, enteropathy with anemia and the loss of protein, macroscopically inflammatory changes as erosions and ulceration, aggravated diverticulosis, and recurrences of ulcerative colitis. During treatment with NSAID the incidence of changes within the intestine is comparable to that within the upper gut. The incidence and character of complications concerning the small and large intestines are still under investigation. Frequently, post-NSAID intestinal changes may not present any clinical signs; it is only a serious complication (haemorrhage, perforation) that becomes the first symptom. Introducing selective COX-2 inhibitors into the treatment has significantly reduced the complications within both upper and lower digestive tract; however, the knowledge of the security profile for these preparations is not yet complete.

Changes in rates of upper gastrointestinal hemorrhage after the introduction of cyclooxygenase-2 inhibitors in British Columbia and Ontario

BACKGROUND

Population rates of upper gastrointestinal (GI) hemorrhage have been observed to increase with the introduction and rapid uptake of selective cyclooxygenase-2 (COX-2) inhibitors. Changes in COX-2 inhibitor use and upper GI bleeding rates in regions with relatively restrictive drug policies (e.g., British Columbia) have not been compared with changes in regions with relatively less restrictive drug policies (e.g., Ontario).

METHODS

We collected administrative data for about 1.4 million people aged 66 years and older in British Columbia and Ontario for the period January 1996 to November 2002. We examined temporal changes in the prevalence of NSAID use and admissions to hospital because of upper GI hemorrhage in both provinces using cross-sectional time series analysis.

RESULTS

During the period studied, the prevalence of NSAID use in British Columbia's population of older people increased by 25% (from 8.7% to 10.9%; p < 0.01), as compared with a 51% increase in Ontario (from 10.9% to 16.5%; p < 0.01). Hospital admissions because of upper GI hemorrhage increased significantly in Ontario by about 16% on average, or about 2 admissions per 10 000 elderly people, above expected values (p < 0.01). A similar increase was not observed in British Columbia.

INTERPRETATION

More restrictive drug coverage policies, although limiting access to drugs and their potential benefits, may protect the population from adverse drug effects.

Evaluation of the efficacy and safety of etoricoxib compared with naproxen in two, 138-week randomised studies of patients with osteoarthritis

OBJECTIVES

To assess the efficacy and safety of etoricoxib 60 mg once daily and naproxen 500 mg twice daily over a 138-week treatment period in patients with osteoarthritis (OA).

METHODS

Two 1-year randomised, double blind, parallel group two-part base studies (part I 12 weeks; part II 40 weeks), followed by an 86-week extension, in patients with OA (hip or knee) were conducted at 80 clinical centres (19 countries). The studies had identical designs. Patients taking placebo in part I received etoricoxib or naproxen (1:1 ratio) in part II and the extension; patients taking etoricoxib or naproxen in part I continued to receive the same treatment throughout the entire length of the studies. Co-primary efficacy end points were patient global assessment of disease status, and WOMAC questionnaire pain subscale and physical function subscale (100 mm VAS). Efficacy over 138 weeks was assessed by graphical analysis. Safety was assessed by observation of adverse experiences and laboratory and physical evaluations.

RESULTS

997 patients entered (615 completed) the base studies. Of these patients, 463 patients entered the extensions. A total of 161 and 152 patients in the etoricoxib and naproxen groups, respectively, completed 138 treatment weeks. Etoricoxib and naproxen showed similar efficacy throughout the 138 weeks of treatment. For etoricoxib and naproxen, respectively, WOMAC pain assessments were 67 and 67 mm (baseline); 28 and 29 mm (1 year), and 34 and 33 mm (138 weeks). Results for the other efficacy end points were similar to those seen with the WOMAC pain assessments. Both etoricoxib and naproxen were generally well tolerated.

CONCLUSION

Both etoricoxib and naproxen demonstrated long-term clinical efficacy for the treatment of OA. Etoricoxib and naproxen were generally well tolerated.

Do selective COX-2 inhibitors increase the risk of cerebrovascular events? A meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the risk of cerebrovascular events (CVEs) associated with selective cyclooxygenase-2 inhibitors (coxibs).

METHOD

Systematic review and meta-analysis of randomized controlled trials (RCTs). A fixed-effect model was used to estimate the odds ratios (ORs) for risk of CVE associated with coxibs compared against placebo, non-selective non-steroidal anti-inflammatory drugs (NSAIDs) and other coxibs.

RESULTS

Forty trials (88 116 patients) were included in the meta-analysis. The overall pooled OR for CVE for any coxib against placebo was 1.03 (95% CI: 0.71, 1.50). Comparing individual coxibs against placebo, we found that celecoxib, rofecoxib, etoricoxib and lumiracoxib were associated with higher CVE risks and valdecoxib was associated with a lower CVE risk, although there were no significant differences detected. There was also no significant difference in risk of CVE when comparing coxibs against any non-selective NSAIDs; the corresponding pooled OR was 0.86 (95% CI: 0.64, 1.16).

CONCLUSION

On the basis of a detailed analysis of available RCTs, there does not appear to be any significant difference in risk of CVEs associated with coxibs when compared against placebo or non-selective NSAIDs. It is likely that the increased risk of thrombotic vascular events associated with coxibs is largely attributable to an increased risk of myocardial infarction, rather than CVEs.