Lee S. Simon

Cyclooxygenase in biology and disease

Cyclooxygenase (COX), the key enzyme required for the conversion of arachidonic acid to prostaglandins was first identified over 20 years ago. Drugs, like aspirin, that inhibit cyclooxygenase activity have been available to the public for about 100 years. In the past decade, however, more progress has been made in understanding the role of cyclooxygenase enzymes in biology and disease than at any other time in history. Two cyclooxygenase isoforms have been identified and are referred to as COX‐1 and COX‐2. Under many circumstances the COX‐1 enzyme is produced constitutively (i.e., gastric mucosa) whereas COX‐2 is inducible (i.e., sites of inflammation). Here, we summarize the current understanding of the role of cyclooxygenase‐1 and ‐2 in different physiological situations and disease processes ranging from inflammation to cancer. We have attempted to include all of the most relevant material in the field, but due to the rapid progress in this area of research we apologize that certain recent findings may have been left out.—DuBois, R. N., Abramson, S. B., Crofford, L., Gupta, R. A., Simon, L. S., van de Putte, L. B. A., Lipsky, P. E. Cyclooxygenase in biology and disease. FASEB J. 12, 1063–1073 (1998)

American College of Rheumatology/European League Against Rheumatism provisional definition of remission in rheumatoid arthritis for clinical trials

Objective Remission in rheumatoid arthritis (RA) is an increasingly attainable goal, but there is no widely used definition of remission that is stringent but achievable and could be applied uniformly as an outcome measure in clinical trials. This work was undertaken to develop such a definition. Methods A committee consisting of members of the American College of Rheumatology, the European League Against Rheumatism, and the Outcome Measures in Rheumatology Initiative met to guide the process and review prespecified analyses from RA clinical trials. The committee requested a stringent definition (little, if any, active disease) and decided to use core set measures including, as a minimum, joint counts and levels of an acute-phase reactant to define remission. Members were surveyed to select the level of each core set measure that would be consistent with remission. Candidate definitions of remission were tested, including those that constituted a number of individual measures of remission (Boolean approach) as well as definitions using disease activity indexes. To select a definition of remission, trial data were analysed to examine the added contribution of patient-reported outcomes and the ability of candidate measures to predict later good radiographic and functional outcomes. Results Survey results for the definition of remission suggested indexes at published thresholds and a count of core set measures, with each measure scored as 1 or less (eg, tender and swollen joint counts, C reactive protein (CRP) level, and global assessments on a 0–10 scale). Analyses suggested the need to include a patient-reported measure. Examination of 2-year follow-up data suggested that many candidate definitions performed comparably in terms of predicting later good radiographic and functional outcomes, although 28-joint Disease Activity Score–based measures of remission did not predict good radiographic outcomes as well as the other candidate definitions did. Given these and other considerations, we propose that a patients RA can be defined as being in remission based on one of two definitions: (1) when scores on the tender joint count, swollen joint count, CRP (in mg/dl), and patient global assessment (0–10 scale) are all ≤1, or (2) when the score on the Simplified Disease Activity Index is ≤3.3. Conclusion We propose two new definitions of remission, both of which can be uniformly applied and widely used in RA clinical trials. The authors recommend that one of these be selected as an outcome measure in each trial and that the results on both be reported for each trial.

OMERACT : An international initiative to improve outcome measurement in rheumatology

OMERACT is the acronym for an international, informally organized network initiated in 1992 aimed at improving outcome measurement in rheumatology. Chaired by an executive committee, it organizes consensus conferences in a 2-yearly cycle that circles the globe. Data driven recommendations are prepared and updated by expert working groups. Recommendations include core sets of measures for most of the major rheumatologic conditions. Since 2002 patients have been actively engaged in the process.

Basic biology and clinical application of specific cyclooxygenase‐2 inhibitors

In summary, COX-2 is a highly regulated gene product that catalyzes the local production of PGs in pathologic and physiologic situations (Figure 1). It is clear that COX-2 is the isoform responsible for production of the PGs that mediate inflammation, pain, and fever. However, the role for COX-2 in normal physiology is still being defined. Specific COX-2 inhibitors represent a significant conceptual advance in therapy for patients with arthritis. Although there is no expectation of superior efficacy, clinical trials suggest that efficacy will be comparable with that of nonselective NSAIDs. Clinical trials demonstrate the potential for clinically meaningful reductions in the incidence of the most serious GI complications found with nonselective NSAIDs, i.e., ulcer, perforation, and GI bleeding. Over the next several years, treatment of large numbers of patients with specific COX-2 inhibitors will help to define the biology of COX-2. The magnitude of this advance in the therapy of rheumatic diseases is yet to be accurately determined, but the development of specific COX-2 inhibitors may afford significant new treatment options for many patients.

Fibromyalgia syndrome module at OMERACT 9: domain construct.

The objective of the module was to (1) establish a core domain set for fibromyalgia (FM) assessment in clinical trials and practice, (2) review outcome measure performance characteristics, (3) discuss development of a responder index for assessment of FM in clinical trials, (4) review objective markers, (5) review the domain of cognitive dysfunction, and (6) establish a research agenda for outcomes research. Presentations at the module included: (1) Results of univariate and multivariate analysis of 10 FM clinical trials of 4 drugs, mapping key domains identified in previous patient focus group: Delphi exercises and a clinician/researcher Delphi exercise, and breakout discussions to vote on possible essential domains and reliable measures; (2) Updates regarding outcome measure status; (3) Update on objective markers to measure FM disease state; and (4) Review of the issue of cognitive dysfunction (dyscognition) in FM. Consensus was reached as follows: (1) Greater than 70% of OMERACT participants agreed that pain, tenderness, fatigue, patient global, multidimensional function and sleep disturbance domains should be measured in all FM clinical trials; dyscognition and depression should be measured in some trials; and stiffness, anxiety, functional imaging, and cerebrospinal fluid biomarkers were identified as domains of research interest. (2) FM domain outcome measures have generally proven to be reliable, discriminative, and feasible. More sophisticated and comprehensive measures are in development, as is a responder index for FM. (3) Increasing numbers of objective markers are being developed for FM assessment. (4) Cognitive dysfunction assessment by self-assessed and applied outcome measures is being developed. In conclusion, a multidimensional symptom core set is proposed for evaluation of FM in clinical trials. Research on improved measures of single domains and composite measures is ongoing.

Reporting disease activity in clinical trials of patients with rheumatoid arthritis: EULAR/ACR collaborative recommendations.

OBJECTIVE To make recommendations on how to report disease activity in clinical trials of rheumatoid arthritis (RA) endorsed by the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR). METHODS The project followed the EULAR standardized operating procedures, which use a three-step approach: 1) expert-based definition of relevant research questions (November 2006); 2) systematic literature search (November 2006 to May 2007); and 3) expert consensus on recommendations based on the literature search results (May 2007). In addition, since this is the first joint EULAR/ACR publication on recommendations, an extra step included a meeting with an ACR panel to approve the recommendations elaborated by the expert group (August 2007). RESULTS Eleven relevant questions were identified for the literature search. Based on the evidence from the literature, the expert panel recommended that each trial should report the following items: 1) disease activity response and disease activity states; 2) appropriate descriptive statistics of the baseline, the endpoints and change of the single variables included in the core set; 3) baseline disease activity levels (in general); 4) the percentage of patients achieving a low disease activity state and remission; 5) time to onset of the primary outcome; 6) sustainability of the primary outcome; 7) fatigue. CONCLUSION These recommendations endorsed by EULAR and ACR will help harmonize the presentations of results from clinical trials. Adherence to these recommendations will provide the readership of clinical trials with more details of important outcomes, while the higher level of homogeneity may facilitate the comparison of outcomes across different trials and pooling of trial results, such as in meta-analyses.

Mononuclear Cell-Conditioned Medium Containing Mononuclear Cell Factor (MCF), Homologous With Interleukin 1, Stimulates Collagen and Fibronectin Synthesis by Adherent Rheumatoid Synovial Cells: Effects of Prostaglandin E2 and Indomethacin

Adherent rheumatoid synovial cells produce and release into supernatant culture medium latent collagenase and PGE2. The levels of collagenase and PGE2 can be increased by a soluble factor present in mononuclear cell-conditioned medium, partially purified by gel-filtration, which has homologies with interleukin 1, and is produced by monocyte/macrophages. The synovial cell cultures produce collagens (procollagens) and fibronectin as well. The factor(s) present in the mononuclear cell conditioned medium which increases medium levels of collagenase PGE2 also stimulates synthesis of total protein as well as types I and III procollagen by the synovial cells. This stimulation by the monocyte factor is augmented in the presence of indomethacin, which blocks endogenous PGE2 production. Medium levels of fibronectin parallel those of procollagen. The addition of exogenous PGE2 abolishes the effect of indomethacin on collagen and fibronectin synthesis. These observations of mononuclear cell-mediated increases in fibronectin synthesis may account for the high levels of fibronectin found by others in rheumatoid synovium and synovial fluids as the increases in collagen synthesis might also explain the fibrosis observed in some rheumatoid joints.

Content and criterion validity of the preliminary core dataset for clinical trials in fibromyalgia syndrome.

Objective. Increasing research interest and emerging new therapies for treatment of fibromyalgia (FM) have led to a need to develop a consensus on a core set of outcome measures that should be assessed and reported in all clinical trials, to facilitate interpretation of the data and understanding of the disease. This aligns with the key objective of the Outcome Measures in Rheumatology (OMERACT) initiative to improve outcome measurement through a data driven, interactive consensus process. Methods. Through patient focus groups and Delphi processes, working groups at previous OMERACT meetings identified potential domains to be included in the core data set. A systematic review has shown that instruments measuring these domains are available and are at least moderately sensitive to change. Most instruments have been validated in multiple languages. This pooled analysis study aims to develop the core data set by analyzing data from 10 randomized controlled trials (RCT) in FM. Results. Results from this study provide support for the inclusion of the following in the core data set: pain, tenderness, fatigue, sleep, patient global assessment, and multidimensional function/health related quality of life. Construct validity was demonstrated with outcome instruments showing convergent and divergent validity. Content and criterion validity were confirmed by multivariate analysis showing R square values between 0.4 and 0.6. Low R square value is associated with studies in which one or more domains were not assessed. Conclusion. The core data set was supported by high consensus among attendees at OMERACT 9. Establishing an international standard for RCT in FM should facilitate future metaanalyses and indirect comparisons.

A Novel Composite Endpoint to Evaluate the Gastrointestinal (GI) Effects of Nonsteroidal Antiinflammatory Drugs Through the Entire GI Tract

Objective. Nonsteroidal antiinflammatory drugs (NSAID) not only cause damage to the upper gastrointestinal (GI) tract but also affect the lower GI tract. To date, there is no endpoint that evaluates serious GI events in the entire GI tract. The objective of this report is to introduce a novel composite endpoint that measures damage to the entire GI tract — clinically significant upper and lower GI events (CSULGIE) — in patients with NSAID-induced GI damage. Methods. We reviewed the data from largescale, multicenter, randomized, clinical trials on lower GI toxicity associated with NSAID use. The rationale for using CSULGIE as a primary endpoint in 2 ongoing trials — the Celecoxib vs Omeprazole and Diclofenac for At-risk Osteoarthritis (OA) and Rheumatoid Arthritis (RA) Patients (CONDOR) trial and the Gastrointestinal Randomized Events and Safety Open-Label NSAID Study (GI-REASONS) — is also discussed. Results. Previous randomized trials focused primarily on damage to the upper GI tract and often neglected the lower GI tract. The CSULGIE endpoint extends the traditional “perforation, obstruction, and bleeding” assessment of upper GI complications by including events in the lower GI tract (small/large bowel) such as perforation, bleeding, and clinically significant anemia. Conclusion. By providing clinicians with a new, descriptive language for adverse events through the entire GI tract, the CSULGIE endpoint has the potential to become a standard tool for evaluating the GI effects of a range of therapies.

A modified Delphi exercise to determine the extent of consensus with OMERACT outcome domains for studies of acute and chronic Gout

Objectives: To reach consensus with recommendations made by an OMERACT Special Interest Group (SIG). Methods: Rheumatologists and industry representatives interested in gout rated and clarified, in three iterations, the importance of domains proposed by the OMERACT SIG for use in acute and chronic gout intervention studies. Consensus was defined as a value of less than 1 of the UCLA/RAND disagreement index. Results: There were 33 respondents (61% response rate); all agreed the initial items were necessary, except “total body urate pool”. Additional domains were suggested and clarification sought for defining “joint inflammation” and “musculoskeletal function”. Items that demonstrated no clear decision were re-rated in the final iteration. There were six highly rated items (rating 1–2) with four slightly lower rating items (rating 3) for acute gout; and 11 highly rated items with eight slightly lower ratings for chronic gout. Conclusions: Consensus is that the following domains be considered mandatory for acute gout studies: pain, joint swelling, joint tenderness, patient global, physician global, functional disability; and for chronic gout studies: serum urate, gout flares, tophus regression, health-related quality of life, functional disability, pain, patient global, physician global, work disability and joint inflammation. Several additional domains were considered discretionary.