Evaluation of in vivo immune complex formation and complement activation in patients receiving intravenous streptokinase

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldThe usefulness of several different methods for detecting immune complex formation and complement activation in the circulation were applied to samples from patients receiving intravenous Streptokinase therapy for myocardial infarction. Streptokinase is a foreign antigen and can cause immune reactions. We collected samples from 13 patients, before Streptokinase administration (baseline), at the end of infusion (1 h), 12 h later and on day 7. We measured IgG containing immune complexes (IgG-IC), free C3d and antibodies to Streptokinase by ELISA, and CR1, C3d and C4d on erythrocytes by flow cytometric assay. Antibodies to Streptokinase are common, as all but two of the patients had measurable antibody levels. During Streptokinase treatment there was a drop in antibody levels, most prominent in those patients who had high baseline levels. At the same time increased levels of free C3d and erythrocyte-bound C3d were observed. After 12 h free C3d was usually back to baseline level, but C3d on erythrocytes was still raised. These data indicate the formation of Streptokinase immune complexes in patients with high Streptokinase antibody levels, and show that these complexes are cleared rapidly from the circulation, leaving more persistent signs of complement activation. We conclude that free C3d is a good indicator of ongoing complement activation, whereas C3d on erythrocytes indicates that complement activation has recently taken place

Evaluation of in vivo immune complex formation and complement activation in patients receiving intravenous streptokinase

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldThe usefulness of several different methods for detecting immune complex formation and complement activation in the circulation were applied to samples from patients receiving intravenous Streptokinase therapy for myocardial infarction. Streptokinase is a foreign antigen and can cause immune reactions. We collected samples from 13 patients, before Streptokinase administration (baseline), at the end of infusion (1 h), 12 h later and on day 7. We measured IgG containing immune complexes (IgG-IC), free C3d and antibodies to Streptokinase by ELISA, and CR1, C3d and C4d on erythrocytes by flow cytometric assay. Antibodies to Streptokinase are common, as all but two of the patients had measurable antibody levels. During Streptokinase treatment there was a drop in antibody levels, most prominent in those patients who had high baseline levels. At the same time increased levels of free C3d and erythrocyte-bound C3d were observed. After 12 h free C3d was usually back to baseline level, but C3d on erythrocytes was still raised. These data indicate the formation of Streptokinase immune complexes in patients with high Streptokinase antibody levels, and show that these complexes are cleared rapidly from the circulation, leaving more persistent signs of complement activation. We conclude that free C3d is a good indicator of ongoing complement activation, whereas C3d on erythrocytes indicates that complement activation has recently taken place

European regulatory perspectives for innovative therapies.

The current regulatory requirements offer accelerated assessment of innovative therapies in Europe. Future perspectives include the need for increased interaction between stakeholders in pharmaceutical development. Development of new, high quality, effective and safe medicines in Europe is the common goal of academia, pharmaceutical industry and regulatory authorities. To achieve this, it is important that regulatory requirements do not hinder innovation and vice versa, innovation cannot be allowed to proceed without concerns for public health. Interaction between stakeholders in pharmaceutical development is of the utmost importance. A dialogue has begun and in the future it will be the responsibility of all stakeholders to ensure continuous exchanges in an environment that is characterised by new scientific advances and global development programmes

Biomarkers and personalised medicine in rheumatoid arthritis: a proposal for interactions between academia, industry and regulatory bodies.

Rheumatoid arthritis (RA) is one of the most appropriate conditions for the application of personalised medicine as a high degree of heterogeneity has been recognised, which remains to be explained. Such heterogeneity is also reflected in the large number of treatment targets and options. A growing number of biologics as well as small molecules are already in use and there are promising new drugs in development. In order to make the best use of treatment options, both targeted and non-targeted biomarkers have to be identified and validated. To this aim, new rules are needed for the interaction between academia and industry under regulatory control. Setting up multi-centre biosample collections with clear definition of access, organising early, possibly non-committing discussions with regulatory authorities, and defining a clear route for the validation, qualification and registration of the biomarker-drug combination are some of the more critical areas where effective collaboration between the drug industry, academia and regulators is needed

Recommendations for an update of 2003 European regulatory requirements for registration of drugs to be used in the treatment of RA.

Since 2003, the European Medicines Agency (EMA) document, 'Points to consider on clinical investigation of medicinal products other than NSAIDs (nonsteroidal anti-inflammatory drugs) for the treatment of rheumatoid arthritis' has provided guidance for the clinical development of both biologic and non-biologic disease-modifying antirheumatic drugs (DMARDs). In the last few years, several new products have been developed or are in development for the treatment of RA, which offer significant efficacy with regard to disease control, including prevention of structural damage and disability. Concurrently, novel insights have been gained with respect to the assessment of disease activity, joint damage and disability. New treatment strategies have been established which relate to early therapy, tight control and rapid switching of medication. Accordingly, several new EULAR/ACR recommendations have been or are being developed. Several important additions and changes are needed in the 2003 guidance to incorporate the current scientific knowledge into clinical trial design for the development of future products. Under the auspices of the Group for the Respect of Ethics and Excellence in Science (GREES), a group of experts in the field of RA and clinical trial design met to provide a consensus recommendation for an update to the 2003 EMA guidance document

Recommendations for the registration of agents for prevention and treatment of glucocorticoid-induced osteoporosis: An update from the Group for the Respect of Ethics and Excellence in Science (Osteoporosis International DOI: 10.1007/s00198-008-0670-7)

[No abstract available