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 analyzed 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 (e.g., 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 followup 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 patient's RA can be defined as being in remission based on one of two definitions: (a) 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 (b) 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. We 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.

Establishing a Public Resource for Acceptable Surrogate Endpoints to Support FDA Marketing Applications.

Following a comprehensive and coordinated effort between CBER and CDER, FDA established a table of acceptable surrogate endpoints (SEs) to support drug marketing applications. The publicly accessible SE Table was first published in 2018 as a response to the 21st Century Cures Act legislation and is updated every 6 months to reflect current FDA thinking. The criteria for the table headings and content were chosen to foster succinctness and consistency, while reflecting the degree of scientific understanding for each listed SE. Prior to the publication of the SE table there was the misconception that FDA only approved drugs based on a limited number of SEs. Contrary to this viewpoint, the SE table demonstrates that FDA frequently uses SEs as they are used in over 100 disease/use and patient population combinations. This article describes the considerations and approach taken when establishing the SE table as well as a discussion of the benefits and limitations of the SE table when used by various stakeholders.

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 patient's 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.

Tuberculosis following the use of etanercept, a tumor necrosis factor inhibitor.

Infliximab, a tumor necrosis factor (TNF) antagonist, is associated with tuberculosis (TB), but it is unknown whether this phenomenon is true of all TNF antagonists. We reviewed 25 cases of TB due to another TNF antagonist, etanercept, that were reported to the US Food and Drug Administration (FDA) between November 1998 and March 2002. Such cases are sometimes incomplete and are subject to underreporting. Fifteen patients received other immunosuppressive medications. The median interval between the receipt of the first dose of etanercept and the diagnosis of TB was 11.5 months. Thirteen patients had extrapulmonary TB at the time of diagnosis. Diagnosis was made on the basis of culture results for 12 patients, biopsy findings for 9, and sputum staining for 4. There were 2 deaths, 1 of which was directly attributed to TB. The estimated number of TB cases reported to the FDA for each person-year of treatment with etanercept (i.e., the "reporting rate") among patients with rheumatoid arthritis (RA) was ~10 cases/100,000 patient-years of exposure. Clinicians considering etanercept for patients with RA should be alert to the possibility of the occurrence of TB, sometimes with an unusual extrapulmonary presentation. It is unclear whether etanercept therapy increases the risk of TB beyond the elevated TB rates already documented for patients with RA.

Using registries to identify adverse events in rheumatic diseases.

The proven effectiveness of biologics and other immunomodulatory products in inflammatory rheumatic diseases has resulted in their widespread use as well as reports of potential short- and long-term complications such as infection and malignancy. These complications are especially worrisome in children who often have serial exposures to multiple immunomodulatory products. Post-marketing surveillance of immunomodulatory products in juvenile idiopathic arthritis (JIA) and pediatric systemic lupus erythematosus is currently based on product-specific registries and passive surveillance, which may not accurately reflect the safety risks for children owing to low numbers, poor long-term retention, and inadequate comparators. In collaboration with the US Food and Drug Administration (FDA), patient and family advocacy groups, biopharmaceutical industry representatives and other stakeholders, the Childhood Arthritis and Rheumatology Research Alliance (CARRA) and the Duke Clinical Research Institute (DCRI) have developed a novel pharmacosurveillance model (CARRA Consolidated Safety Registry [CoRe]) based on a multicenter longitudinal pediatric rheumatic diseases registry with over 8000 participants. The existing CARRA infrastructure provides access to much larger numbers of subjects than is feasible in single-product registries. Enrollment regardless of medication exposure allows more accurate detection and evaluation of safety signals. Flexibility built into the model allows the addition of specific data elements and safety outcomes, and designation of appropriate disease comparator groups relevant to each product, fulfilling post-marketing requirements and commitments. The proposed model can be applied to other pediatric and adult diseases, potentially transforming the paradigm of pharmacosurveillance in response to the growing public mandate for rigorous post-marketing safety monitoring.

Successes achieved and challenges ahead in translating biomarkers into clinical applications.

Biomarkers are important tools for identifying and stratifying diseases, predicting their progression and determining the effectiveness, safety, and doses of therapeutic interventions. This is important for common chronic diseases such as diabetic nephropathy, osteoporosis, and rheumatoid arthritis which affect large numbers of patients worldwide. This article summarizes the current knowledge of established and novel biomarkers for each of these diseases as presented at the 2008 AAPS/ACCP joint symposium "Success Achieved and Challenges Ahead in Translating Biomarkers into Clinical Applications," in Atlanta, Georgia. The advantages and disadvantages of various proteomic, metabolomic, genomic, and imaging biomarkers are discussed in relation to disease diagnosis and stratification, prognosis, drug development, and potential clinical applications. The use of biomarkers as a means to determine therapeutic interventions is also considered. In addition, we show that biomarkers may be useful for adapting therapies for individual needs by allowing the selection of patients who are most likely to respond or react adversely to a particular treatment. They may also be used to determine whether the development of a novel therapy is worth pursuing by informing crucial go/no go decisions around safety and efficacy. Indeed, regulatory bodies now suggest that effective integration of biomarkers into clinical drug development programs is likely to promote the development of novel therapeutics and more personalized medicine.

Guillain-Barré and Miller Fisher syndromes occurring with tumor necrosis factor alpha antagonist therapy.

OBJECTIVE: Diverse neurologic syndromes have been described in association with tumor necrosis factor alpha (TNFalpha) antagonist therapy for inflammatory arthritides and Crohn's disease. The objective of this study was to review the occurrence and clinical features of Guillain-Barré syndrome and its variant, the Miller Fisher syndrome, during TNFalpha antagonist therapy. METHODS: The postmarketing database of the US Food and Drug Administration (FDA) was searched, following our experience with a patient with rheumatoid arthritis in whom the Miller Fisher syndrome variant of the Guillain-Barré syndrome developed while he was receiving infliximab therapy. RESULTS: Our index patient had a neurologic illness defined initially by ataxia and dysarthria, which fluctuated in relation to each subsequent infliximab infusion and, after 6 months, culminated in areflexic flaccid quadriplegia. In addition, 15 patients in whom Guillain-Barré syndrome developed following TNFalpha antagonist therapy were identified from the FDA database. Guillain-Barré syndrome developed following infliximab therapy in 9 patients, following etanercept therapy in 5 patients, and following adalimumab therapy in 1 patient. Among the 13 patients for whom followup data were available, 1 patient experienced no resolution, 9 patients had partial resolution, and 3 patients had complete resolution of Guillain-Barré syndrome following therapy. CONCLUSION: An association of Guillain-Barré syndrome with TNFalpha antagonist therapy is supported by the worsening of neurologic symptoms that occurred in our index patient following each infusion of infliximab, and by the temporal association of this syndrome with TNFalpha antagonist therapy in 15 other patients. An acute or subacute demyelinating polyneuropathy should be considered a potential adverse effect of TNFalpha antagonist therapy.

Preparation and analysis of phosphorylated proteins.

The function of cells of the immune system is regulated in part by engagement of specific receptors on the cell surface by soluble ligands or ligands presented on the surface of other cells. One of the major mechanisms by which cell-surface receptor engagement influences cellular function is by activating protein kinases and increasing the phosphorylation of critical cellular proteins. There are two major categories of protein kinases: serine/threonine kinases which phosphorylate both serine and threonine residues; and tyrosine kinases which phosphorylate tyrosine residues exclusively. By metabolically labeling cells with (32)P, as described in this unit, the phosphorylation state of cellular proteins can be analyzed and changes occurring with receptor stimulation can be examined. Phosphoamino acid analysis is also described to determine whether serine, threonine, or tyrosine residues are phosphorylated, thereby indicating which category of protein kinase is responsible. A protocol for phosphopeptide mapping is provided to allow the investigator to produce a "fingerprint" of the peptides that are phosphorylated, providing information regarding the sites of phosphorylation.

Antiphosphotyrosine blotting.

Antiphosphotyrosine blotting is a technique for detecting tyrosine-phosphorylated substrates by the use of antibodies that recognize these residues on a wide variety of proteins. This unit describes conditions for cell lysis and immunoprecipitation of proteins with an antiphosphotyrosine antibody, followed by electrophoretic separation, immunoblotting, and color detection of the blotted proteins. This combination of steps provides particularly sensitive conditions for the detection of tyrosine-phosphorylated substrates, but also gives good results for any protein transferred to nitrocellulose, including whole-cell lysates or proteins immunoprecipitated with another antibody. Although the alkaline phosphatase color-detection system has the advantage of providing superior resolution and higher sensitivity without the use of any radioactivity, the (125)I-labeled Staphylococcus protein A detection system is described for use in conjunction with the blotting protocol.

Infectious complications of biologic treatments of rheumatoid arthritis.

Agents that block the action of tumor necrosis factor-alpha and recombinant interleukin-1 have been shown to be effective biologic treatment modalities in patients with rheumatoid arthritis. Given the immunosuppressive effects of tumor necrosis factor-alpha and interleukin-1 blockers, infections have emerged as possible complications of using these agents, an observation foreshadowed in prelicensure animal studies. At this time, hundreds of thousands of patients have received these drugs, and a wide variety of infectious complications has been reported, among which reactivation tuberculosis is most notable. Case reports alone, however, do not necessarily reflect a causal association between a therapeutic product and an adverse event. The authors review the infectious complications of the use of these agents as reported in the medical literature from November 2001 through October 2002.

Leukocytoclastic vasculitis associated with tumor necrosis factor-alpha blocking agents.

OBJECTIVE: To describe the clinical features of leukocytoclastic vasculitis (LCV) associated with the use of tumor necrosis factor-alpha (TNF-alpha) blockers. METHODS: The Adverse Events Reporting System (AERS) of the US Food and Drug Administration (FDA) was queried for reports of patients who developed LCV during or after starting etanercept or infliximab from date of approval of each agent through September 6, 2002. RESULTS: Thirty-five cases of LCV were identified, 20 following etanercept administration and 15 following infliximab administration. Seventeen of the 35 (48.5%) were biopsy-proven cases and the others had skin lesions that were clinically typical for LCV. Twenty-two of 35 (62.8%) patients had complete or marked improvement of skin lesions upon stopping the TNF-alpha blocker. Three patients who had received etanercept had continuing lesions despite discontinuation of the drug; one of these patients improved when switched to infliximab. One patient who received infliximab was reported to have continuing lesions despite discontinuation of the drug and treatment with prednisone and antihistamines. Six patients experienced a positive rechallenge (recurrence of LCV on restarting therapy with a TNF-alpha blocker) and 3 patients a negative rechallenge phenomenon. LCV lesions improved in patients despite continuing use of concomitant medications reportedly associated with LCV. CONCLUSION: Therapy with TNF-alpha blocking agents may be associated with the development of LCV. Skin lesions improved on discontinuation of anti-TNF-alpha therapy in most patients. Other causes of LCV should be excluded, and evaluation for systemic involvement with appropriate investigations is recommended.

Life-threatening histoplasmosis complicating immunotherapy with tumor necrosis factor alpha antagonists infliximab and etanercept.

OBJECTIVE: Two tumor necrosis factor alpha (TNFalpha) antagonists were recently licensed in the US. Infliximab was licensed in 1998 for the treatment of Crohn's disease (CD), and since 1999, it has been licensed in combination with methotrexate for treatment of rheumatoid arthritis (RA). Etanercept was licensed in 1998 for treatment of RA and, more recently, for juvenile RA and psoriatic arthritis. Because of potential immunosuppression related to use of anti-TNFalpha agents, we sought to identify postlicensure cases of opportunistic infection, including histoplasmosis, in patients treated with these products. METHODS: The US Food and Drug Administration's (FDA) passive surveillance database for monitoring postlicensure adverse events was reviewed to identify all reports received through July 2001 of histoplasmosis in patients treated with either infliximab or etanercept. RESULTS: Ten cases of Histoplasma capsulatum (HC) infection were reported: 9 associated with infliximab and 1 associated with etanercept. In patients treated with infliximab, manifestations of histoplasmosis occurred within 1 week to 6 months after the first dose and typically included fever, malaise, cough, dyspnea, and interstitial pneumonitis. Of the 10 patients with histoplasmosis, 9 required treatment in an intensive care unit, and 1 died. All patients had received concomitant immunosuppressive medications in addition to infliximab or etanercept, and all resided in HC-endemic regions. CONCLUSION: Postlicensure surveillance suggests that acute life-threatening histoplasmosis may complicate immunotherapy with TNFalpha antagonists, particularly infliximab. Histoplasmosis should be considered early in the evaluation of patients who reside in HC-endemic areas in whom infectious complications develop during treatment with infliximab or etanercept.