Impact of concomitant low-dose aspirin on the safety and tolerability of naproxen and esomeprazole magnesium delayed-release tablets in patients requiring chronic nonsteroidal anti-inflammatory drug therapy: an analysis from 5 Phase III studies

Predictive value of gastrointestinal symptoms and patient risk factors for NSAID-associated gastrointestinal ulcers defined by endoscopy? Insights from a pooled analysis of two naproxen clinical trials

OBJECTIVE

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used to treat pain and rheumatic conditions. To facilitate patient management, we determined the predictive value of gastrointestinal (GI) symptoms and risk factors for the development of NSAID-associated GI injuries.

METHODS

Post-hoc analysis of pooled data from naproxen treatment arms of two identical, randomized, double-blind, controlled phase 3 trials in arthritis patients at risk of GI adverse events. Endoscopic incidence of GI ulcers at baseline, and 1, 3, and 6 months was employed as a surrogate parameter for GI injury. For GI symptom analysis, Severity of Dyspepsia Assessment questionnaire was used. For GI risk factor analysis, the high risk factors: previous GI injury, concomitant selective serotonin reuptake inhibitors or corticosteroids, ulcer history, concomitant low-dose aspirin, and age >65 years were employed.

RESULTS

Data of 426 naproxen patients were analyzed. Distribution of GI symptoms between patients with and without ulcer was similar; about one third of patients developing an ulcer reported no GI pain symptoms. GI symptoms experienced under naproxen treatment were thus not indicative of GI injury. The proportion of patients developing an ulcer increased with the number of risk factors present, however, about a quarter of patients without any of the analyzed risk factors still developed an ulcer.

CONCLUSION

GI symptoms and the number of risk factors are not reliable predictors of NSAID-induced GI injury to decide which patients need gastroprotection and will lead to a large group of patients with GI injuries. A preventive rather than reactive approach should be taken.

Synthesis of 4-Methoxy-1, 3-Benzenediolylhydrazones and Evaluation of Their Anti-Platelet Aggregation Activity

In our present investigation, a series of novel 4-methoxy-1,3-benzenediolyl-hydrazones were designed and synthesized, and their ability to inhibit platelet aggregation was evaluated by adenosine diphosphate (ADP) and arachidonic acid (AA). The structures of the synthesized compounds were confirmed by spectral data. Results demonstrated that the activities of all compounds excelled the positive drug Picotamide (25.1% inhibition rate) and seven compounds (PNN01, PNN03, PNN05, PNN07, PNN09, PNN12, and PNN14) have efficiently inhibited platelet aggregation even higher than Clopidogrel (37.6% inhibition rate) induced by AA. Among them, PNN07 (39.8% inhibition rate) was considered as the most potent analogue. Evaluation of cytotoxic activity of the compounds against L929 cell line revealed that none of the compounds have significant cytotoxicity. Thus, diolylhydrazones derives are potential to be antiplatelet aggregation inhibitors and maybe working in AA-induced selectively.

Celecoxib for osteoarthritis

BACKGROUND

Osteoarthritis (OA) is the most common form of arthritis and is caused by degeneration of the joint cartilage and growth of new bone, cartilage and connective tissue. It is often associated with major disability and impaired quality of life. There is currently no consensus on the best treatment to improve OA symptoms. Celecoxib is a selective non-steroidal anti-inflammatory drug (NSAID).

OBJECTIVES

To assess the clinical benefits (pain, function, quality of life) and safety (withdrawals due to adverse effects, serious adverse effects, overall discontinuation rates) of celecoxib in osteoarthritis (OA).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and clinical trials registers up to April 11, 2017, as well as reference and citation lists of included studies. Pharmaceutical companies and authors of published articles were contacted.

SELECTION CRITERIA

We included published studies (full reports in a peer reviewed journal) of prospective randomized controlled trials (RCTs) that compared oral celecoxib versus no intervention, placebo or another traditional NSAID (tNSAID) in participants with clinically- or radiologically-confirmed primary OA of the knee or hip, or both knee and hip.

DATA COLLECTION AND ANALYSIS

Two authors independently performed data extraction, quality assessment, and compared results. Main analyses for patient-reported outcomes of pain and physical function were conducted on studies with low risk of bias for sequence generation, allocation concealment and blinding of participants and personnel.

MAIN RESULTS

We included 36 trials that provided data for 17,206 adults: 9402 participants received celecoxib 200 mg/day, and 7804 were assigned to receive either tNSAIDs (N = 1869) or placebo (N = 5935). Celecoxib was compared with placebo (32 trials), naproxen (6 trials) and diclofenac (3 trials). Studies were published between 1999 and 2014. Studies included participants with knee, hip or both knee and hip OA; mean OA duration was 7.9 years. Most studies included predominantly white participants whose mean age was 62 (± 10) years; most participants were women. There were no concerns about risk of bias for performance and detection bias, but selection bias was poorly reported in most trials. Most trials had high attrition bias, and there was evidence of selective reporting in a third of the studies. Celecoxib versus placeboCompared with placebo celecoxib slightly reduced pain on a 500-point Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain scale, accounting for 3% absolute improvement (95% CI 2% to 5% improvement) or 12% relative improvement (95% CI 7% to 18% improvement) (4 studies, 1622 participants). This improvement may not be clinically significant (high quality evidence).Compared with placebo celecoxib slightly improved physical function on a 1700-point WOMAC scale, accounting for 4% absolute improvement (95% CI 2% to 6% improvement), 12% relative improvement (95% CI 5% to 19% improvement) (4 studies, 1622 participants). This improvement may not be clinically significant (high quality evidence).There was no evidence of an important difference for withdrawals due to adverse events (Peto OR 0.99, 95% CI 0.85 to 1.15) (moderate quality evidence due to study limitations).Results were inconclusive for numbers of participants experiencing any serious AEs (SAEs) (Peto OR 0.95, 95% CI 0.66 to 1.36), gastro-intestinal events (Peto OR 1.91, 95% CI 0.24 to 14.90) and cardiovascular events (Peto OR 3.40, 95% CI 0.73 to 15.88) (very low quality evidence due to serious imprecision and study limitations). However, regulatory agencies have warned of increased cardiovascular events for celecoxib. Celecoxib versus tNSAIDsThere were inconclusive results regarding the effect on pain between celecoxib and tNSAIDs on a 100-point visual analogue scale (VAS), showing 5% absolute improvement (95% CI 11% improvement to 2% worse), 11% relative improvement (95% CI 26% improvement to 4% worse) (2 studies, 1180 participants, moderate quality evidence due to publication bias).Compared to a tNSAID celecoxib slightly improved physical function on a 100-point WOMAC scale, showing 6% absolute improvement (95% CI 6% to 11% improvement) and 16% relative improvement (95% CI 2% to 30% improvement). This improvement may not be clinically significant (low quality evidence due to missing data and few participants) (1 study, 264 participants).Based on low or very low quality evidence (downgraded due to missing data, high risk of bias, few events and wide confidence intervals) results were inconclusive for withdrawals due to AEs (Peto OR 0.97, 95% CI 0.74 to 1.27), number of participants experiencing SAEs (Peto OR 0.92, 95% CI 0.66 to 1.28), gastro-intestinal events (Peto OR 0.61, 0.15 to 2.43) and cardiovascular events (Peto OR 0.47, 95% CI 0.17 to 1.25).In comparisons of celecoxib and placebo there were no differences in pooled analyses between our main analysis with low risk of bias and all eligible studies. In comparisons of celecoxib and tNSAIDs, only one outcome showed a difference between studies at low risk of bias and all eligible studies: physical function (6% absolute improvement in low risk of bias, no difference in all eligible studies).No studies included in the main comparisons measured quality of life. Of 36 studies, 34 reported funding by drug manufacturers and in 34 studies one or more study authors were employees of the sponsor.

AUTHORS' CONCLUSIONS

We are highly reserved about results due to pharmaceutical industry involvement and limited data. We were unable to obtain data from three studies, which included 15,539 participants, and classified as awaiting assessment. Current evidence indicates that celecoxib is slightly better than placebo and some tNSAIDs in reducing pain and improving physical function. We are uncertain if harms differ among celecoxib and placebo or tNSAIDs due to risk of bias, low quality evidence for many outcomes, and that some study authors and Pfizer declined to provide data from completed studies with large numbers of participants. To fill the evidence gap, we need to access existing data and new, independent clinical trials to investigate benefits and harms of celecoxib versus tNSAIDs for people with osteoarthritis, with longer follow-up and more direct head-to-head comparisons with other tNSAIDs.

Synthesis and mechanistic evaluation of novel N'-benzylidene-carbohydrazide-1H-pyrazolo[3,4-b]pyridine derivatives as non-anionic antiplatelet agents

Cardiovascular diseases (CVDs) account for over 17 million deaths globally each year, with atherosclerosis as the underlying cause of most CVDs. Herein we describe the synthesis and in vitro mechanistic evaluation of novel N'-benzylidene-carbohydrazide-1H-pyrazolo[3,4-b]pyridines (3-22) designed as non-anionic antiplatelet agents and presenting a 30-fold increase in potency compared to aspirin. The mechanism underlying their antiplatelet activity was elucidated by eliminating potential targets through a series of in vitro assays including light transmission aggregometry, clot retraction, and quantitative ELISA, further identifying the reduction in biosynthesis of thromboxane B2 as their main mechanism of action. The intrinsic fluorescence of the compounds permits their binding to platelet membranes to be readily monitored. In silico structure-activity relationship, molecular docking and dynamics studies support the biological profile of the series revealing the molecular basis of their activity and their potential as future molecular therapeutic agents.

Patient-centered Outcomes with Concomitant Use of Proton Pump Inhibitors and Other Drugs

PURPOSE

We performed a systematic review of patient-centered outcomes after the concomitant use of proton pump inhibitors (PPIs) and other drugs.

METHODS

We searched 4 databases in July 2016 to find studies that reported mortality and morbidity after the concomitant use of PPIs and other drugs. We conducted direct meta-analyses using a random-effects model and graded the quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation working group approach.

FINDINGS

We included data from 17 systematic reviews and meta-analyses, 16 randomized controlled trials, and 16 observational studies that examined the concomitant use of PPIs with medications from 10 drug classes. Low-quality evidence suggests that the use of PPIs is associated with greater morbidity when administered with antiplatelet drugs, bisphosphonates, antibiotics, anticoagulants, metformin, mycophenolate mofetil, or nelfinavir. Concomitant PPIs reduce drug-induced gastrointestinal bleeding and are associated with greater docetaxel and cisplatin response rates in patients with metastatic breast cancer. For demonstrated statistically significant relative risks and benefits from concomitant PPIs, the magnitudes of the effects are small, with <100 attributable events per 1000 patients treated, and the effects are inconsistent among specific drugs. Among individual PPIs, the concomitant use of pantoprazole or esomeprazole, but not omeprazole or lansoprazole, is associated with an increased risk for all-cause mortality, nonfatal myocardial infarction, or stroke. Clopidogrel is associated with a greater risk for myocardial infarction compared with prasugrel. Conflicting results between randomized controlled trials and observational studies and high risk for bias in the body of evidence lessened our confidence in the results.

IMPLICATIONS

Available evidence suggests a greater risk for adverse patient outcomes after the concomitant use of PPIs and medications from 9 drug classes and warns against inappropriate drug combinations.

Efficacy of naproxen with or without esomeprazole for pain and inflammation in patients after bilateral third molar extractions: A double blinded crossover study

Background

Using a double-blinded randomized crossover design, this study aimed to evaluate acute postoperative pain management, swelling and trismus in 46 volunteers undergoing extractions of the two lower third molars, in similar positions, at two different appointments who consumed a tablet of either NE (naproxen 500 mg + esomepraz ole 20 mg) or only naproxen (500 mg) every 12 hours for 4 days.

Material and Methods

Parameters were analyzed: self-reported pain intensity using a visual analog scale (VAS) pre- and postoperative mouth opening; incidence, type and severity of adverse reactions; total quantity consumed of rescue medication; and pre- and postoperative swelling.

Results

Female volunteers reported significantly more postoperative pain at 1, 1.5, 2, 3 and 4hrs after surgery while also taking their first rescue medication at a time significantly earlier when consuming NE when compared to naproxen (3.7hrs and 6.7hrs). Conversely, no differences were found between each drug group in males.

Conclusions

In conclusion, throughout the entire study, pain was mild after using either drug in both men and women with pain scores on average well below 40mm (VAS), although in women naproxen improved acute postoperative pain management when compared to NE.

Key words:Oral surgery, third molar, pain, naproxen, esomeprazole, NSAIDs.

New approaches in tail-bleeding assay in mice: improving an important method for designing new anti-thrombotic agents

This report describes a modified, simple, low-cost and more sensitive method to determine bleeding patterns and haemoglobin concentration in a tail-bleeding assay using BALB/c mice and tail tip amputation. The cut tail was immersed in Drabkin's reagent to promote erythrocyte lysis and haemoglobin release, which was monitored over 30 min. The operator was blinded to individual conditions of the mice, which were treated with either saline (NaCl 0.15m), DMSO (0.5%) or clinical anti-thrombotic drugs. Our experimental protocols showed good reproducibility and repeatability of results when using Drabkin's reagent than water. Thus, the use of Drabkin's reagent offered a simple and low-cost method to observe and quantify the bleeding and rebleeding episodes. We also observed the bleeding pattern and total haemoglobin loss using untreated animals or those under anti-coagulant therapy in order to validate the new Drabkin method and thus confirm that it is a useful protocol to quantify haemoglobin concentrations in tail-bleeding assay. This modified method provided a more accurate results for bleeding patterns in mice and for identifying new anti-thrombotic drugs.

Synthesis and antiplatelet activity of antithrombotic thiourea compounds: biological and structure-activity relationship studies

The incidence of hematological disorders has increased steadily in Western countries despite the advances in drug development. The high expression of the multi-resistance protein 4 in patients with transitory aspirin resistance, points to the importance of finding new molecules, including those that are not affected by these proteins. In this work, we describe the synthesis and biological evaluation of a series of N,N'-disubstituted thioureas derivatives using in vitro and in silico approaches. New designed compounds inhibit the arachidonic acid pathway in human platelets. The most active thioureas (compounds 3d, 3i, 3m and 3p) displayed IC₅₀ values ranging from 29 to 84 µM with direct influence over in vitro PGE₂ and TXA₂ formation. In silico evaluation of these compounds suggests that direct blockage of the tyrosyl-radical at the COX-1 active site is achieved by strong hydrophobic contacts as well as electrostatic interactions. A low toxicity profile of this series was observed through hemolytic, genotoxic and mutagenic assays. The most active thioureas were able to reduce both PGE₂ and TXB₂ production in human platelets, suggesting a direct inhibition of COX-1. These results reinforce their promising profile as lead antiplatelet agents for further in vivo experimental investigations.

Platelets: still a therapeutical target for haemostatic disorders

Platelets are cytoplasmatic fragments from bone marrow megakaryocytes present in blood. In this work, we review the basis of platelet mechanisms, their participation in syndromes and in arterial thrombosis, and their potential as a target for designing new antithrombotic agents. The option of new biotechnological sources is also explored.