Leprosy Skin Test Antigens Phase 1
Condition: Leprosy
MeSH terms: Leprosy
Study type: Interventional
Phase: Phase 1

Summary: 
      This is a small Phase I trial to evaluate the safety of the use as skin test antigens of the
      immunologically active proteins from the soluble/cytosol and insoluble cell wall of
      Mycobacterium leprae. The overall objective is to generate new leprosy skin-test antigens,
      equivalent to tuberculin-PPD in the tuberculosis context, to be used (I) for the early
      diagnosis of leprosy; and (ii) as epidemiological tools to measure the incidence of disease.
      Evaluating new leprosy skin test antigens may provide a better way to diagnose leprosy in its
      early stages of infection. With the early administration of drug therapy, infected
      individuals can then be cured of this disease before nerve damage occurs or nodules
      (lepromas) start to develop on the skin. Ten healthy, leprosy-unexposed, tuberculin-negative
      volunteers, 18-40 years old, from within the staff of the Mycobacteria Research Laboratories,
      Department of Microbiology, Colorado State University, Fort Collins, Colorado, will be
      selected.
    

Detailed description: 
      This is a small Phase I trial to evaluate the safety of the use as skin test antigens of the
      immunologically active proteins from the soluble/cytosol and insoluble cell wall of
      Mycobacterium leprae. The overall objective is to generate new leprosy skin-test antigens,
      equivalent to tuberculin-PPD in the tuberculosis context, to be used (I) for the early
      diagnosis of leprosy; and (ii) as epidemiological tools to measure the incidence of disease.
      Evaluating new leprosy skin test antigens may provide a better way to diagnose leprosy in its
      early stages of infection. With the early administration of drug therapy, infected
      individuals can then be cured of this disease before nerve damage occurs or nodules
      (lepromas) start to develop on the skin. Ten healthy, leprosy-unexposed, tuberculin-negative
      volunteers, ages 18-40 years old, from within the staff of the Mycobacteria Research
      Laboratories, Department of Microbiology, Colorado State University, Fort Collins, Colorado,
      will be selected for this study. The volunteers will be recruited by direct contact after
      placing notices in the Department of Microbiology at Colorado State University. There are
      approximately 40 faculty/staff/students in this population and all are routinely tested (PPD
      skin-testing or chest X-ray) by the staff at the Hartshorn Health Service Center in the
      context of the Department's tuberculosis research. Five individuals will be selected for
      testing MLSA-LAM and five will receive MLCwA. Each will receive single 0.1 ml intracutaneous
      injections of three titrated doses (1, 10 and 25 )lg/ml) of the skin-test antigen, one of
      mock antigen (i.e., physiological saline), and one of control antigen (the product now in
      use; Rees MLSA, 10 )lg), divided equally between the subject's two arms. Results will be
      recorded at 15 min, 48 h, 72 h, and 28 days post-injection. The test dose will be
      administered with a sterile1 ml syringe calibrated in tenths and fitted with a sterile,
      one-half inch, 26 or 27 gauge needle. The rubber stopper of the vial will be wiped with a
      sterile piece of cotton moistened with alcohol and allowed to dry.It is expected that all
      concentrations of the two leprosy skin test antigens will evoke similar negative responses.
      If so, all three concentrations will be used for subsequent studies. This protocol is linked
      to study 98-202.
    

Intervention name(s): MLCwA; MLSA-LAM; Mock Antigen
Intervention type(s): Biological; Biological; Other
Intervention description(s): Antigen MLSA-LAM is a pellet extracted 3x followed by removal of SDS by column chromatography. Contains many of the same proteins; Antigen MLSA-LAM is derived from M. leprae extract following sonication and centrifugation, leaving the cytosol (MLSA). Contains soluble protein antigens of M. leprae; Physiological saline
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Leprosy, skin test, MLSA-LAM, MLCwA, diagnosis, Protocol 98-202