The Use of Anti-CD4 Monoclonal Antibody (mAb)-Fragment for the Imaging of Chronic Inflammation in Patients With Active Rheumatoid Arthritis
Condition: Rheumatoid Arthritis; Polyarthritis; Rheumatism; Autoimmune Disease; Inflammation
MeSH terms: Arthritis; Arthritis, Rheumatoid; Rheumatic Diseases; Autoimmune Diseases; Inflammation
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      Rheumatoid arthritis (RA) is a disease with a large economic impact due to the long lasting
      disabling nature of the disease. Furthermore, diagnosis of the disease is difficult and only
      a scheme with different symptoms is used to diagnose rheumatoid arthritis, often only by
      probability.

      Due to the fact that effective disease modifying pharmacological treatment is available and
      should be started early in established cases of RA, in combination with the adverse effect
      potential of these substances (e.g. methotrexate), a fast reliable diagnostic tool to
      diagnose rheumatoid arthritis would be highly appreciated by the medical community and the
      patients. Furthermore, for invasive treatments (surgery, puncture), an imaging method to
      display the activity pattern in different joints would be a major advantage.

      For the evaluation of the effectiveness of pharmacological therapy in rheumatoid arthritis,
      up to now, radiological measurements of the destruction process of the joints are used. This
      method has the disadvantage that it is time consuming insofar as changes in the radiological
      images must occur. It allows only an evaluation if the joints are destructed (which should be
      excluded by the new therapy regimen). Again, a quantifiable method for the determination of
      the effects of new therapeutic approaches would be highly appreciated.
    

Detailed description: 
      The substance will be used as iv injection due to the protein nature of the antibody and, to
      ensure a fast distribution within the body. The study will be performed as an open clinical
      trial due to the fact that the applied radiation has to be documented; the use of "placebo"
      radiation would be unethical.

      It is expected, that the new antibody fragment with its radioactive linkage will display an
      image of the activity distribution of the disease. Due to the fact that only patients with
      active disease have to be imaged and, to allow for comparison of the activity and the
      clinical distribution of the disease, this proof of concept study (phase I study) will be
      performed in patients with active disease. Healthy volunteers could not display an activity
      pattern of the disease. Furthermore, it seems to be unethical to use volunteers for studies
      with radioactivity with such a risk/benefit ratio (radiation risks vs. missing chance of
      display of tissue distribution) in a proof of concept study.
    

Intervention name(s): Fab-fragment of Anti-human CD4
Intervention type(s): Radiation
Intervention description(s): Sterile lyophilized Powder for Preparation of a Solution and sterile labelling Buffer labelling with Tc99m-Pertechnetat Intravenous injection
Intervention MeSH terms: Immunoglobulin Fab Fragments
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: monoclonal antibody; diagnostics; RA; Immunoglobulins; molecular target; Tc99m-pertechnetate; Fab-fragment of Anti-human CD4; Radiopharmaceutical; chronic inflammatory diseases; active Rheumatoid Arthritis