Search PubMed⌕ Search

Biomedical subjects

Joel M Kremer

Publications and source records attributed to Joel M Kremer.

At least 19 recordsLinked to original sources
PubMed2006

Effects of abatacept in patients with methotrexate-resistant active rheumatoid arthritis: a randomized trial.

BACKGROUND: The selective co-stimulation modulator abatacept demonstrated efficacy for treating rheumatoid arthritis in early clinical studies. OBJECTIVE: To evaluate the effects of abatacept in patients with persistent, active rheumatoid arthritis despite methotrexate treatment. DESIGN: One-year, multicenter, randomized, double-blind, placebo-controlled trial (November 2002 to October 2004). SETTING: 116 centers worldwide. PATIENTS: 652 patients with active rheumatoid arthritis despite methotrexate treatment. INTERVENTION: Once-monthly infusion of a fixed dose of abatacept, approximately 10 mg/kg of body weight, or placebo. MEASUREMENTS: Co-primary end points were a 20% improvement in American College of Rheumatology (ACR) response criteria (ACR 20) at 6 months, clinically meaningful improvements in physical function, and change from baseline in joint erosion score at 1 year. RESULTS: Four hundred thirty-three and 219 patients were randomly assigned to abatacept or placebo, respectively, and 385 (89%) and 162 (74%), respectively, completed 1 year of treatment. In a modified intention-to-treat analysis, 6-month ACR 20, ACR 50, and ACR 70 responses were 67.9% for abatacept versus 39.7% for placebo (difference, 28.2 percentage points [95% CI, 19.8 to 36.7 percentage points]), 39.9% for abatacept versus 16.8% for placebo (difference, 23.0 percentage points [CI, 15.0 to 31.1 percentage points]), and 19.8% for abatacept versus 6.5% for placebo (difference, 13.3 percentage points [CI, 7.0 to 19.5 percentage points]), respectively. At 1 year, the responses increased to 73.1% for abatacept versus 39.7% for placebo (difference, 33.4 percentage points [CI, 25.1 to 41.7 percentage points]), 48.3% for abatacept versus 18.2% for placebo (difference, 30.1 percentage points [CI, 21.8 to 38.5 percentage points]), and 28.8% for abatacept versus 6.1% for placebo (difference, 22.7 percentage points [CI, 15.6 to 29.8 percentage points]), respectively (P < 0.001 for all). Physical function significantly improved in 63.7% versus 39.3% of patients (P < 0.001). At 1 year, abatacept statistically significantly slowed the progression of structural joint damage compared with placebo. Abatacept-treated patients had a similar incidence of adverse events (87.3% vs. 84.0%; difference, 3.3 percentage points [CI, -2.5 to 9.1 percentage points]) and a higher incidence of prespecified serious infections (2.5% vs. 0.9%; difference, 1.6 percentage points [CI, -0.3 to 3.6 percentage points]) and infusion reactions (acute, 8.8% vs. 4.1%; difference, 4.7 percentage points [CI, 0.9 to 8.4 percentage points]; peri-infusional, 24.5% vs. 16.9%; difference, 7.6 percentage points [CI, 1.2 to 14.0 percentage points]) compared with placebo recipients. LIMITATIONS: The study involved only 1 group of patients over 1 year. CONCLUSIONS: Abatacept statistically significantly reduced disease activity in patients with rheumatoid arthritis and an inadequate response to methotrexate. Longer treatment in different patient populations is needed to establish its appropriate role in rheumatoid arthritis.

Abatacept↗
PubMed2006

Etanercept treatment in adults with established rheumatoid arthritis: 7 years of clinical experience.

OBJECTIVE: To evaluate safety and efficacy of longterm etanercept treatment in patients with disease modifying antirheumatic drug (DMARD) refractory rheumatoid arthritis (RA). METHODS: Safety results are reported for 714 patients who received etanercept in one of 7 initial trials or a longterm extension. Efficacy results are reported for 581 patients who enrolled in the extension. RESULTS: Of the 714 patients enrolled in the initial trials, 581 (81%) enrolled in the extension, and 388 (54%) patients are continuing to receive etanercept therapy. The longest individual treatment was 8.2 years, with 3139 total patient-years of etanercept exposure. Rates of serious adverse events (overall rate=14.8 events/100 patient-yrs), serious infections (overall rate=4.2 events/100 patient-yrs), cancer (overall rate=1.0 events/100 patient-yrs), and deaths (overall rate=0.7 events/100 patient-yrs) were stable each year, through 8 years of etanercept exposure. For 356 patients who completed 6 years of etanercept treatment, response rates were ACR20=73%, ACR50=52%, ACR70=27%, DAS28 CRP good response=52%, and DAS28 CRP remission=37% of patients. Similar responses occurred in 167 patients who completed Year 7. Doses of concomitant methotrexate or corticosteroids were reduced in many patients who maintained clinical responses. CONCLUSION: The safety profile of etanercept was consistent over time, with rates of adverse events similar to those reported for patients with RA in general. Durable clinical responses were observed in some patients for 7 years or more. The benefit-to-risk ratio for longterm etanercept treatment remains highly favorable.

Adolescent↗
PubMed2006

Risk genotypes in folate-dependent enzymes and their association with methotrexate-related side effects in rheumatoid arthritis.

OBJECTIVE: Methotrexate (MTX) is an antifolate agent that is often associated with toxicity. This study investigated whether risk genotypes for folate-dependent enzymes are associated with the toxicity of MTX in patients with rheumatoid arthritis (RA). METHODS: Blood was collected for analysis in a muticenter, cross-sectional study of RA patients who had been receiving MTX for at least 1 month prior to enrollment, and side effects occurring at the time of a single study visit were recorded. Low-penetrance risk genotypes in methylenetetrahydrofolate reductase (MTHFR) 677TT, thymidylate synthase (TSER) *2/*2 (variable number of tandem repeats), amino imidazole ribonucleotide transformylase (ATIC) 347GG, and serine hydroxymethyltransferase (SHMT1) 1420CC were measured and summed to constitute the toxicogenetic index specific to each patient. Statistical analyses consisted of logistic regression models with clustered-center effects, and associations with risk genotypes were expressed as adjusted odds ratios (ORs). RESULTS: Among 214 patients enrolled at 4 study sites, a total of 67 patients (31%) presented with a side effect (gastrointestinal event, headache, lethargy, alopecia, cough, or dyspnea). Risk genotypes associated with side effects in the central nervous system were MTHFR 677TT (OR 3.3, P < 0.01) and SHMT1 1420CC (OR 2.4, P < 0.05). ATIC 347GG was associated with gastrointestinal side effects (OR 3.0, P < 0.01), while TSER*2/*2 (OR 5.4, P < 0.01) and SHMT1 1420CC (OR 3.2, P < 0.01) were associated with alopecia. The toxicogenetic index ranged from 0 to 3 (median 1). An index of 3 was associated with an approximately 7-fold higher likelihood of having a side effect compared with an index of 0 (P < 0.01). CONCLUSION: These data suggest that a composite index of the cumulative risk genotypes in folate-dependent enzymes may be an effective means of profiling RA patients who develop side effects to MTX.

Aged↗
PubMed2005

The CORRONA database.

BACKGROUND: Large, long-term databases are needed in order to provide information on the safety and efficacy of new agents used in the treatment of rheumatoid arthritis (RA) and psoriatic arthritis (PsA). These databases can provide data which is well beyond what is available from industry-sponsored investigations. METHODS: The structure, governance, content, context and developmental plan of the CORRONA database are described. RESULTS: The CORRONA database has grown from start up in 2002 to the largest independent database in North America which collects data from both rheumatologists and patients at the time of a clinical encounter. Data are collected as often as every 3 months in RA and every 6 months in PsA. As of the time of this writing, the CORRONA database consists of approximately 9000 patients with RA and 1000 with PsA. Data can be used to elucidate toxicities found in frequencies which would be considerably less common than can be uncovered in industry-sponsored investigations. In addition, actual prescribing patterns and responses in clinical practice can be investigated and described. CONCLUSION: After 3 years of data collection, the CORRONA database is now appropriately able to make significant contributions to our understanding of the safety, efficacy of drugs, as well as demographic, and socioeconomic profiles of patients with RA and PsA. It has evolved from a nascent database to a mature one poised to make significant contributions.

Antirheumatic Agents↗
PubMed2005

Treatment of rheumatoid arthritis with the selective costimulation modulator abatacept: twelve-month results of a phase iib, double-blind, randomized, placebo-controlled trial.

OBJECTIVE: To determine the clinical efficacy, safety, and immunogenicity of abatacept (CTLA-4Ig), a selective costimulation modulator, in patients with rheumatoid arthritis (RA) that has remained active despite methotrexate (MTX) therapy. METHODS: This was a 12-month, multicenter, randomized, double-blind, placebo-controlled study. A total of 339 patients with active RA despite MTX therapy were randomly assigned to receive 10 mg/kg abatacept (n = 115), 2 mg/kg abatacept (n = 105), or placebo (n = 119). This report focuses on the results observed at month 12 of a phase IIb trial. RESULTS: A significantly greater percentage of patients treated with 10 mg/kg abatacept met the American College of Rheumatology 20% improvement criteria (achieved an ACR20 response) at 1 year compared with patients who received placebo (62.6% versus 36.1%; P < 0.001). Greater percentages of patients treated with 10 mg/kg abatacept also achieved ACR50 responses (41.7% versus 20.2%; P < 0.001) and ACR70 responses (20.9% versus 7.6%; P = 0.003) compared with patients who received placebo. For patients treated with 10 mg/kg abatacept, there were also statistically significant and clinically important improvements in modified Health Assessment Questionnaire scores compared with patients who received placebo (49.6% versus 27.7%; P < 0.001). Abatacept at a dosage of 10 mg/kg elicited an increase in rates of remission (Disease Activity Score in 28 joints of <2.6) compared with placebo at 1 year (34.8% versus 10.1%; P < 0.001). The incidence of adverse events was comparable between the groups, and no significant formation of neutralizing antibodies was noted. CONCLUSION: Abatacept was associated with significant reductions in disease activity and improvements in physical function that were maintained over the course of 12 months in patients with RA that had remained active despite MTX treatment. Abatacept was found to be well tolerated and safe over the course of 1 year. Abatacept in combination with MTX has the potential to play an important role in future RA therapy.

Abatacept↗
PubMed2005

Selective costimulation modulators: a novel approach for the treatment of rheumatoid arthritis.

T cells have a central role in the orchestration of the immune pathways that contribute to the inflammation and joint destruction characteristic of rheumatoid arthritis (RA). The requirement for a dual signal for T-cell activation and the construction of a fusion protein that prevents engagement of the costimulatory molecules required for this activation has led to a new approach to RA therapy. This approach is mechanistically distinct from other currently used therapies; it targets events early rather than late in the immune cascade, and it results in immunomodulation rather than complete immunosuppression. The fusion protein abatacept is a selective costimulation modulator that avidly binds to the CD80/CD86 ligands on an antigen-presenting cell, resulting in the inability of these ligands to engage the CD28 receptor on the T cell. Abatacept dose-dependently reduces T-cell proliferation, serum concentrations of acute-phase reactants, and other markers of inflammation, including the production of rheumatoid factor by B cells. Recent studies have provided consistent evidence that treatment with abatacept results in a rapid onset of efficacy that is maintained over the course of treatment in patients with inadequate response to methotrexate and anti-tumor necrosis factor therapies. This efficacy includes patient-centered outcomes and radiographic measurement of disease progression. Abatacept has also demonstrated a very favorable safety profile to date. This article reviews the rationale for this therapeutic approach and highlights some of the recent studies that demonstrate the benefits obtained by using abatacept. This clinical experience indicates that abatacept is a significant addition to the therapeutic armamentarium for the management of patients with RA.

Abatacept↗
PubMed2005

Use of combination of leflunomide with biological agents in treatment of rheumatoid arthritis.

An Expert Panel Meeting was held in May 2004 to assess experience with combination therapy with leflunomide and biological agents in the treatment of rheumatoid arthritis (RA), to identify both optimal use of such combinations and precautions for use. Eleven published prospective or retrospective studies were reviewed, principally evaluating combination of leflunomide with infliximab, as well as patient registry data. Available data suggest that combination therapies are more efficacious than monotherapies, reflecting the complementarity of mechanisms of action. Information on side effects remains contradictory, and tolerability of these combinations may vary between different patient groups. In some studies, tolerability is equivalent to that seen with monotherapy; in others a high rate of adverse events has led to frequent treatment discontinuation. Dermatological reactions may be a specific side effect of these combination therapies. Combination therapy is considered justified for treatment of patients diagnosed early who are at risk for rapid progression and for patients who fail to respond to monotherapy. The majority of participants favored adding biological agents to a previously established leflunomide monotherapy rather than starting both treatments simultaneously. On the other hand, combination therapy should be considered with caution in patients with a history of treatment failure, with hepatic comorbidity, or with other autoimmune disease, and in immunocompromised patients. When considering initiation of combination therapy, it is important to provide full information to the patient on the potential benefits and risks of such treatment and to integrate patients as far as possible into the decision-making process.

Antibodies, Monoclonal↗
PubMed2004

Once-weekly administration of 50 mg etanercept in patients with active rheumatoid arthritis: results of a multicenter, randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To evaluate the safety, efficacy, and pharmacokinetics of 50 mg etanercept administered subcutaneously once weekly in adult patients with active rheumatoid arthritis (RA). METHODS: Four hundred twenty RA patients were randomized to receive, in a blinded manner, the study drug for up to 16 weeks: 214 patients received 50 mg etanercept once weekly, 153 received 25 mg etanercept twice weekly, and 53 received placebo for 8 weeks followed by 25 mg etanercept twice weekly for 8 weeks. Efficacy and safety were assessed at weeks 8 and 16. Pharmacokinetic analyses were performed on serum samples from patients at selected study sites. The primary efficacy end point was achievement of the American College of Rheumatology (ACR) 20% improvement criteria (ACR20 response) at week 8. RESULTS: An ACR20 response was achieved at week 8 by 50% of the patients receiving 50 mg etanercept once weekly, by 49% of the patients receiving 25 mg etanercept twice weekly, and by 19% of the patients in the placebo group (P </= 0.0001 for each etanercept group versus placebo). Similarly, achievement of the ACR50 response was attained by 18% of patients in each of the 2 etanercept groups, compared with 6% of patients in the placebo group (P < 0.03 for each comparison). Pharmacokinetics of the 2 etanercept regimens were similar at steady state. No clinically significant differences in efficacy or safety were observed between the 2 etanercept groups. CONCLUSION: Safety, efficacy, and pharmacokinetics were comparable between the 2 etanercept dosing regimens. Thus, comparable clinical outcomes are to be expected when patients are treated with etanercept administered either as 50 mg once weekly or as 25 mg twice weekly.

Adult↗
PubMed2004

Treatment of rheumatoid arthritis with etanercept.

Etanercept is effective in the treatment of rheumatoid arthritis (RA)when used as monotherapy and in combination with methotrexate(MTX). Radiographic progression of disease was slowed significantly when the drug was used for a 24-month period and was statistically significantly better than MTX. In addition to its use in RA,etanercept is approved by the U.S. Food and Drug Administration for other rheumatologic conditions, including psoriatic arthritis,ankylosing spondylitis, and juvenile chronic arthritis.

Antirheumatic Agents↗
PubMed2004

Leflunomide.

Leflunomide is a low-molecular weight, synthetic, oral agent specifically developed for immunosuppression. Because of activity in animal models, leflunomide was tested in rheumatoid arthritis(RA). These investigations have demonstrated that leflunomide reduces the clinical symptoms and signs of RA, improves health related quality of life, and retards structural damage. Leflunomide has been evaluated in RA patients as monotherapy and in combination with methotrexate. Close monitoring for adverse events with particular attention for monitoring liver enzymes for hepatic toxicity is important during treatment with leflunomide.

Antirheumatic Agents↗
PubMed2004

Cytotoxic T-lymphocyte antigen 4-immunoglobulin in rheumatoid arthritis.

It is apparent that the potential to significantly affect the immune response exists through artificial modulation of a system of molecules on the surface of T cells that has been designed to specifically provide on-off switches to support or abrogate the activation of T cells. This approach holds considerable promise because it avoids toxicities associated with cell lysis, while theoretically specifically affecting only those T cells, which are being continuously stimulated to become activated. Although there is presently a paucity of studies in humans on the clinical effects of cytotoxic T-lymphocyte antigen 4-immunoglobulin in patients who have rheumatoid arthritis, the existing studies indicate a clear therapeutic value with this approach.

Abatacept↗
PubMed2003

Treatment of rheumatoid arthritis by selective inhibition of T-cell activation with fusion protein CTLA4Ig.

BACKGROUND: Effective new therapies are needed for rheumatoid arthritis. Current therapies target the products of activated macrophages; however, T cells also have an important role in rheumatoid arthritis. A fusion protein--cytotoxic T-lymphocyte-associated antigen 4-IgG1 (CTLA4Ig)--is the first in a new class of drugs known as costimulation blockers being evaluated for the treatment of rheumatoid arthritis. CTLA4Ig binds to CD80 and CD86 on antigen-presenting cells, blocking the engagement of CD28 on T cells and preventing T-cell activation. A preliminary study showed that CTLA4Ig may be effective for the treatment of rheumatoid arthritis. METHODS: We randomly assigned patients with active rheumatoid arthritis despite methotrexate therapy to receive 2 mg of CTLA4Ig per kilogram of body weight (105 patients), 10 mg of CTLA4Ig per kilogram (115 patients), or placebo (119 patients) for six months. All patients also received methotrexate therapy during the study. The clinical response was assessed at six months with use of the criteria of the American College of Rheumatology (ACR), which define the response according to its extent: 20 percent (ACR 20), 50 percent (ACR 50), or 70 percent (ACR 70). Additional end points included measures of the health-related quality of life. RESULTS: Patients treated with 10 mg of CTLA4Ig per kilogram were more likely to have an ACR 20 than were patients who received placebo (60 percent vs. 35 percent, P<0.001). Significantly higher rates of ACR 50 and ACR 70 responses were seen in both CTLA4Ig groups than in the placebo group. The group given 10 mg of CTLA4Ig per kilogram had clinically meaningful and statistically significant improvements in all eight subscales of the Medical Outcomes 36-Item Short-Form General Health Survey. CTLA4Ig was well tolerated, with an overall safety profile similar to that of placebo. CONCLUSIONS: In patients with active rheumatoid arthritis who were receiving methotrexate, treatment with CTLA4Ig significantly improved the signs and symptoms of rheumatoid arthritis and the health-related quality of life. CTLA4Ig is a promising new therapy for rheumatoid arthritis.

Abatacept↗