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V Strand

Publications and source records attributed to V Strand.

At least 55 records · Page 3Linked to original sources
PubMed2000

Endpoints: consensus recommendations from OMERACT IV. Outcome Measures in Rheumatology.

The goal of the 'Outcome Measures in Rheumatology' (OMERACT) process is to select domains and/or outcome measures for clinical trials in each defined disease category according to truth, discrimination and feasibility. OMERACT IV, held in Cancun, Mexico, April 1998, included the module 'Systemic Lupus Erythematosus (SLE)', designed to define a preliminary core set of outcome domains for randomized controlled trials and longitudinal observational studies (LOS). Although specific measures to be used in clinical trials of SLE have yet to be determined, both randomized controlled trials and longitudinal observation studies groups recommended that outcome be assessed in terms of disease activity and damage in all organ systems involved, as well as by health related quality of life, meaningful to patients, and adverse events. These recommendations were ratified by the majority of participants. In a heterogeneous patient population such as SLE, it is recognized that any individual measure of clinical response may reflect only a portion of what might be termed the 'true outcome'. A responder index could integrate such relatively independent measures of outcome into a single assessment, potentially increasing statistical power and decreasing sample size. Results from randomized controlled trials currently underway assessing these outcome domains are eagerly awaited, and are expected to rapidly advance the field.

Clinical Trials as Topic↗
PubMed2000

Leflunomide: efficacy and safety in clinical trials for the treatment of rheumatoid arthritis.

Leflunomide is a new disease modifying antirheumatic drug (DMARD) that inhibits lymphocyte proliferation by blocking dihydroorotate dehydrogenase (DHODH), the enzyme critical for the production of pyrimidine necessary for DNA synthesis. Through this mode of action, leflunomide inhibits the lymphocyte proliferation associated with the clonal expansion of T cells in rheumatoid arthritis (RA). In clinical trials, leflunomide was superior to placebo and comparable to sulfasalazine and methotrexate for improving both the signs and symptoms of RA. Leflunomide was also superior to placebo and sulfasalazine and comparable to methotrexate in overall improvement of physical function. Leflunomide was equivalent to methotrexate and sulfasalazine in retarding disease progression measured radiographically. Due to its unique mode of action in the treatment of RA, leflunomide shows value in combination therapy with methotrexate for patients refractory to methotrexate alone. The most common adverse reactions associated with leflunomide therapy include gastrointestinal symptoms, allergic reactions, reversible alopecia and elevated liver enzymes. Adverse events were generally mild to moderate, and resolved without complication. The results of phase II and phase III clinical trials indicate that leflunomide is a safe and efficacious drug for the treatment of RA.

Journal Article↗
PubMed2000

Biologic agents in the treatment of rheumatoid arthritis.

Advances in the understanding of the pathogenesis of rheumatoid arthritis (RA) as well as improved biotechnology has enabled selective targeting of the pathogenic elements of disease. Targeting cell recruitment through adhesion molecules has been shown to be successful in pre-clinical murine models. Results of studies of an anti-ICAM-1 monoclonal antibody and anti-sense oligonucleotides have been encouraging. An alternate approach to inhibiting recruitment has been the targeting of chemoattractant molecules ie. chemokines. Important advances have been made in cytokine directed therapy targeting TNFalpha and IL-1. TNF antagonists (anti-TNF monoclonal antibody/soluble TNF receptor Fc fusion protein) have resulted in rapid and substantial improvement in signs and symptoms of disease as well as disease modification, shown by slowing of radiological progression. IL-1 receptor antagonist protein appears to have a significant effect on radiological progression despite a modest effect on symptoms and signs. Studies using anti-inflammatory cytokines such as IL-10 are in progress. A more recent therapeutic approach has been to target T-cell activation by interfering with co-stimulatory complexes such as CD40L/CD40 and CD28/CD80 and CD86. Both pre-clinical and preliminary clinical studies in human subjects support the concept. Another approach involving T-cell receptor peptide vaccination with VB peptides over-utilized in RA synovium has shown to be beneficial. Targeting the cytokines driving T-cells in the RA synovium ie. IL-12 & IL-15 has also proven beneficial in animal studies. Recent attention has also been directed toward the invading synovial fibroblast using Fas-FasL mediated apoptosis. Pre-clinical studies in which angiogenesis and osteoclast activation are targeted have been encouraging. In conclusion, the proof of principle has been established that selective targeting of pathogenic elements of disease results in substantial improvement in signs and symptoms as well as disease progression. Improved efficacy is expected with more aggressive targeting of the pathogenic elements.

Animals↗
PubMed2000

Issues involved in a metaanalysis of rheumatoid arthritis radiographic progression. Analysis issues.

Missing data in controlled clinical trials may create uncertainty in the results of a study based on non-missing data. We used 4 approaches of sensitivity analysis to address this problem. Radiographic progression data were used from a randomized controlled trial of patients with rheumatoid arthritis treated with leflunomide, methotrexate, or placebo for 12 months as an example. The mean change from baseline of the Sharp total radiographic score was the primary efficacy variable for the evaluation of leflunomide in comparison with placebo in the retardation of radiographic progression. Computer simulations were used in some of these approaches. The proportion of missing radiographic data was 26.4%. Result from the non-missing data showed that leflunomide was highly statistically significantly better than placebo in the retardation of radiographic progression. Results from the sensitivity analysis showed that radiographic data are sufficiently robust that it is unlikely that the missing data would have changed the conclusions from the analysis based on non-missing data. The potential effect of missing data in the results of a clinical trial may be addressed by various methods of sensitivity analysis. Computer simulation can be a useful tool in some of these approaches.

Arthritis, Rheumatoid↗
PubMed1999

Treatment of active rheumatoid arthritis with leflunomide compared with placebo and methotrexate. Leflunomide Rheumatoid Arthritis Investigators Group.

CONTEXT: Leflunomide is a reversible inhibitor of de novo pyrimidine synthesis shown to be effective in a phase 2 trial in 402 patients with active rheumatoid arthritis (RA). OBJECTIVE: To compare the efficacy and safety of leflunomide treatment with placebo and methotrexate treatment in patients with active RA. DESIGN: Randomized, double-blind, placebo, and active-controlled 12-month study. SETTING: Forty-seven university and private rheumatology practices in the United States and Canada. PATIENTS: Diagnosis of RA by the American College of Rheumatology (ACR) criteria for duration of 6 months or longer and no previous methotrexate treatment. INTERVENTION: Leflunomide treatment (20 mg/d), placebo, or methotrexate treatment (7.5-15 mg/wk). MAIN OUTCOME MEASURES: American College of Rheumatology success rate (completed 52 weeks of treatment and met the ACR > or = 20% response criteria), disease progression as assessed by x-ray films, and improvement in function and health-related quality of life using the intent-to-treat population. RESULTS: The 482 patients studied were predominantly women (mean age, 54 years; mean disease duration, 6.7 years) for whom a mean of 0.8 disease-modifying antirheumatic drugs had failed. The ACR response and success rates for patients receiving leflunomide treatment (52% and 41%, respectively) and methotrexate treatment (46% and 35%, respectively) were significantly higher than those for patients receiving placebo (26% and 19%, respectively) (P<.001), and they were statistically equivalent, with mean time to initial response at 8.4 weeks for patients receiving leflunomide vs 9.5 weeks for patients receiving methotrexate therapy. X-ray analyses demonstrated less disease progression with leflunomide (P=.001) and methotrexate (P = .02) therapy than with placebo. Leflunomide and methotrexate treatment improved measures of physical function and health-related quality of life significantly more than placebo (P<.001 and P<.05, respectively). Common adverse events for patients receiving leflunomide treatment included gastrointestinal complaints, skin rash, and reversible alopecia. Asymptomatic transaminase elevations resulted in treatment discontinuations for 7.1% of patients receiving leflunomide therapy, 1.7% of patients receiving placebo, and 3.3% of patients receiving methotrexate therapy. CONCLUSIONS: Clinical responses following administration of leflunomide, a new therapeutic agent for the treatment of RA, were statistically superior to those with placebo and equivalent to those with methotrexate treatment. Both active treatments improved signs and symptoms of active RA, delayed disease progression as demonstrated by x-ray films, and improved function and health-related quality of life.

Adult↗
PubMed1999

Pharmacokinetics, safety, and efficacy of combination treatment with methotrexate and leflunomide in patients with active rheumatoid arthritis.

OBJECTIVE: To examine the safety and pharmacokinetics of and clinical response to leflunomide, a de novo pyrimidine synthesis inhibitor, when administered to patients with active rheumatoid arthritis (RA) who have been receiving long-term methotrexate therapy. METHODS: This was an open-label, 52-week study in which 30 patients with RA that remained active despite therapy with methotrexate at 17+/-4 mg/week (mean +/- SD) for > or =6 months were given leflunomide, 10-20 mg/day. Patients were assessed for adverse effects, pharmacokinetic measurements of leflunomide and methotrexate, and clinical response by American College of Rheumatology (ACR) 20% response criteria. RESULTS: Twenty-three patients completed 1 year of treatment. No significant pharmacokinetic interactions between leflunomide and methotrexate were noted. This combination therapy was generally well tolerated clinically, with the exception of elevations of liver enzyme levels. Seven patients withdrew from the treatment regimen: 2 withdrawals were voluntary, 3 were due to persistent elevation of plasma transaminase levels, and 2 were due to lack of efficacy. Of the patients, 16 (53%) met ACR 20% response criteria. Two met ACR criteria for remission after 1 year. CONCLUSION: The combination of methotrexate and leflunomide has therapeutic potential in RA.

Adult↗
PubMed1999

Function and health-related quality of life: results from a randomized controlled trial of leflunomide versus methotrexate or placebo in patients with active rheumatoid arthritis. Leflunomide Rheumatoid Arthritis Investigators Group.

OBJECTIVE: To assess the efficacy of leflunomide or methotrexate compared with placebo in improving function and health-related quality of life in patients with active rheumatoid arthritis (RA), and to examine correlations between response status (as defined by the American College of Rheumatology [ACR] response criteria) and improvement in these measures. METHODS: This 52-week, multicenter, doubleblind, controlled trial compared responses to the Health Assessment Questionnaire (HAQ), modified Health Assessment Questionnaire (MHAQ), Problem Elicitation Technique (PET), Medical Outcomes Study Short Form 36 (SF-36), and questions regarding work productivity among 3 treatment groups (leflunomide, methotrexate, and placebo). Improvement in the PET top 5 and SF-36 scales and component scores were compared with ACR response rates. RESULTS: Clinically meaningful and statistically significant (P<0.0001) improvement in measures of function and heath-related quality of life (MHAQ scores, all scales and disability index of the HAQ, weighted top 5 score of the PET, 5 of 8 scales and physical component score of the SF-36, and work productivity) was seen during treatment with leflunomide in comparison with placebo. Methotrexate administration resulted in significant improvements (P<0.05) in comparison with placebo in the MHAQ scores, HAQ disability index, weighted top 5 score of the PET, physical component score of the SF-36, and bodily pain scale. Compared with methotrexate, leflunomide administration resulted in significantly (P<0.01) more improvement in the MHAQ scores, 5 of 8 scales and disability index of the HAQ, weighted top 5 score of the PET, and 2 of 8 scales and physical component score of the SF-36. Improvements in the PET score, SF-36 physical component score, and work productivity correlated with the ACR responder rates of > or =20% and > or =50% improvement. CONCLUSION: Significant improvements in function and health-related quality of life occurred in patients with RA during treatment with leflunomide or methotrexate. These findings were clinically meaningful and correlated with the ACR response status.

Adjuvants, Immunologic↗
PubMed1999

Mechanism of action for leflunomide in rheumatoid arthritis.

Leflunomide (Arava) has recently been approved by the Food and Drug Administration for the treatment of rheumatoid arthritis (RA). This approval was based on data from a double-blind, multicenter trials in the United States (leflunomide versus methotrexate versus placebo) in which leflunomide was superior to placebo and similar to methotrexate (Strand et al., Arch. Intern. Med., in press, 1999). In a multicenter European trial, leflunomide was similar to sulfasalazine in efficacy and side effects (Smolen et al., Lancet 353, 259-266, 1999). Both methotrexate and leflunomide retarded the rate of radiolographic progression, entitling them to qualify as disease-modifying agents (Strand et al., Arch. Intern. Med., in press, 1999). Leflunomide is an immunomodulatory drug that may exert its effects by inhibiting the mitochondrial enzyme dihydroorotate dehydrogenase (DHODH), which plays a key role in the de novo synthesis of the pyrimidine ribonucleotide uridine monophosphate (rUMP). The inhibition of human DHODH by A77 1726, the active metabolite of leflunomide, occurs at levels (approximately 600 nM) that are achieved during treatment of RA. We propose that leflunomide prevents the expansion of activated and autoimmune lymphocytes by interfering with the cell cycle progression due to inadequate production of rUMP and utilizing mechanisms involving p53. The relative lack of toxicity of A77 1726 on nonlymphoid cells may be due to the ability of these cells to fulfill their ribonucleotide requirements by use of salvage pyrimidine pathway, which makes them less dependent on de novo synthesis.

Animals↗
PubMed1999

Recent advances in the treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA) affects about 0.5% to 1% of the population worldwide. Because there is no cure for this disease, the goal of therapy is to control the underlying inflammatory process and maintain or improve function. This article reviews 4 new treatments for patients with RA: leflunomide, etanercept, infliximab, and the protein A immunoadsorption column with plasmapheresis therapy.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Biologic agents and innovative interventional approaches in the management of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a difficult disease to study, having a variable disease course characterized by exacerbations and remissions. A variety of biologic agents are under investigation as potential treatments for SLE. These products are designed to specifically interfere with the following immunologic processes: T cell activation/T cell-B cell collaboration, production of anti-double-stranded DNA antibodies, deposition of anti-double-stranded DNA antibody complexes, complement activation, and immune complex deposition and cytokine activation and modulation. More aggressive interventions include gene therapy and stem cell transplantation. Immunomodulatory agents recently examined in patients with SLE include: thalidomide, AS101, 2' chlordeoxyadenosine, mycophenolate mofetil, and bindarit. Additional innovative pharmaceutical treatments include the mild androgen dehydroepiandrosterone, selective estrogen receptor modulators, and the prolactin inhibitor, bromocriptine. A variety of these biologic and pharmaceutical agents offer promise as potential therapies. Active participation in clinical trial efforts to develop international consensus regarding trial methodology and outcome measures are crucial to the development of these innovative therapies.

Animals↗
PubMed1999

Imaging in rheumatoid arthritis: results of group discussions.

None of the current scoring methods for radiological damage in rheumatoid arthritis (RA) is ideal. The objective for RA imaging at OMERACT IV was to start discussion about the problems and applicability of the current scoring methods for radiological damage and to start discussion on the challenge of new imaging techniques. The RA imaging module comprised preconference reading material, plenary sessions, small group discussions, and a plenary report of the group sessions, combined with interactive voting. The OMERACT filter guided the discussions. Priorities for further research in imaging studies were: (1) pathologies versus features on radiographs; (2) relation with longterm outcome; and (3) definition of minimum clinically important difference.

Arthritis, Rheumatoid↗
PubMed1999

Leflunomide for the treatment of rheumatoid arthritis.

Leflunomide treatment appears to offer an alternative to methotrexate and sulfasalazine and is a welcome addition to the therapeutic armamentarium for treating active RA. Leflunomide treatment for more than 12 months results in clinically meaningful improvements in disease-specific measures of physical function. The phase 3 trials have shown leflunomide to be as effective as methotrexate and sulfasalazine and an option for initial DMARD therapy. As with all new agents, the long-term safety and value of leflunomide will be determined by use in the clinic.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Patient based methods for assessing adverse events in clinical trials in rheumatology. Progress report for the OMERACT Drug Toxicity Working Party. Outcome Measures in Rheumatology.

There has been increasing recognition in recent years that the measurement of drug related toxicities in rheumatology clinical trials has been sub-optimal. The OMERACT Drug Toxicity Working Party was established to address this issue. The first task of the working party was to identify a minimum set of attributes of drug related toxicity that would be important to patients, clinicians, investigators, and policymakers. The working party then developed consensus on a standard set of properties for instruments to measure these attributes. Existing instruments in the field of rheumatology were ascertained by literature review and by contact with experts in the field. Four instruments were ascertained and evaluated using the guidelines developed by the working party. This report outlines the progress and preliminary results of these activities.

Antirheumatic Agents↗
PubMed1999

Outcome measures to be used in clinical trials in systemic lupus erythematosus.

The optimal outcome measures to be employed in clinical trials of systemic lupus erythematosus (SLE) have yet to be determined. Useful instruments should assess disease outcome in terms of all organ system involvement, as well as measures important to the patient. This article reviews those outcome measures that have been utilized in cohort studies in SLE, as well as their limited use in randomized clinical trials (RCT). Six disease activity measures have been developed: British Isles Lupus Assessment Group Scale (BILAG), European Consensus Lupus Activity Measure (ECLAM), Lupus Activity Index (LAI), National Institutes of Health SLE Index Score (SIS), Systemic Lupus Activity Measure (SLAM), and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). They have been validated in cohort studies as reflecting change in disease activity, and against each other. RCT utilizing SLAM, SLEDAI, BILAG, ECLAM, SIS, SLAM, SLEDAI are ongoing. It is recommended that the disease activity index of choice be selected; but simultaneous computer generation of multiple indices will facilitate comparisons across therapeutic interventions. A damage index has been developed and validated as the Systemic Lupus International Cooperating Clinics (SLICC)/American College of Rheumatology (ACR) Damage Index or SDI. In several cohort studies it has been shown sensitive to change over time, and to reflect cumulative disease activity. There is no health status or disability instrument specific to SLE. The Medical Outcomes Survey (SF-20) captures health status/health related quality of life (HRQOL) better than the Health Assessment Questionnaire (HAQ) in patients with SLE, but does not adequately reflect fatigue. The SF-36 does assess fatigue, and correlates closely with the SF-20. These data indicate that any individual measure of clinical response to a therapeutic intervention in SLE may reflect only a portion of what might be termed the "true outcome." Based on this work, the way is now paved to attempt to develop consensus on the important domains to be measured in clinical trials in SLE, the most appropriate instruments to use and the minimal clinically important differences in their results.

Clinical Trials as Topic↗
PubMed1999

Randomized clinical trials and longitudinal observational studies in systemic lupus erythematosus: consensus on a preliminary core set of outcome domains.

The OMERACT module on systemic lupus erythematosus (SLE) dealt with the definition of preliminary core sets of outcome domains for randomized clinical trials (RCT) and longitudinal observational studies (LOS). After lectures introducing the problems and addressing the key issues, 6 discussion groups, 3 each for LOS and RCT, discussed and weighted more than a dozen possible items for use as outcome domains. The means of the respective 3 groups were calculated. For both RCT and LOS the same outcome domains received more than 10 of a total maximum of 100 points: disease activity, health related quality of life (HRQOL), damage, and toxicity/adverse events. However, the weights for HRQOL and damage were different for LOS and RCT. A final vote led to the acceptance of these 4 variables as a preliminary core set for outcome in SLE by more than 80% of the participants. This core set will allow for improved design, performance, and evaluation of future studies in SLE. However, a number of domains not included in the core set were regarded as important for further analysis and research.

Decision Making↗
PubMed1998

T cell receptor peptide vaccination in rheumatoid arthritis: a placebo-controlled trial using a combination of Vbeta3, Vbeta14, and Vbeta17 peptides.

OBJECTIVE: Restricted T cell receptor (TCR) gene usage has been demonstrated in animal models of autoimmune disease and has resulted in the successful use of TCR peptide therapy in animal studies. This clinical trial was undertaken to determine the safety and efficacy of a combination of Vbeta3, Vbeta14, and Vbeta17 TCR peptides in Freund's incomplete adjuvant (IFA) in patients with rheumatoid arthritis (RA). METHODS: A double-blind, placebo-controlled, multicenter, phase II clinical trial was undertaken using IR501 therapeutic vaccine, which consists of a combination of 3 peptides derived from TCRs (Vbeta3, Vbeta14, and Vbeta17) in IFA. A total of 99 patients with active RA received either 90 microg (n = 31) or 300 microg (n = 35) of IR501 or IFA alone (n = 33) as a control. The study medication and placebo were administered as a single intramuscular injection (1 ml) at weeks 0, 4, 8, and 20. RESULTS: Treatment with IR501 was safe and well tolerated. None of the patients discontinued the trial because of treatment-related adverse events. Efficacy was measured according to the American College of Rheumatology 20% improvement criteria. Using these criteria, patients in both IR501 dosage groups showed improvement in disease activity. In the most conservative analysis used to evaluate efficacy, an intent-to-treat analysis including all patients who enrolled, the 90-microg dosage group showed a statistically significant improvement compared with control patients at the 20-week time point after the third injection. Trends toward improvement were shown in both the 90-microg and the 300-microg dosage groups at week 24 after the fourth injection. CONCLUSION: IR501 therapeutic vaccine therapy was safe and well tolerated, immunogenic, and demonstrated clinical improvement in RA patients. Additional clinical trials are planned to confirm and extend these observations.

Adult↗