clinical evaluation of t.r.u.e. test® panel 3.2 allergens: dose response

Conditions: Contact Dermatitis

Summary: we propose a prospective, multi-center, double-blind, randomized study comparing the diagnostic performance (primary) and safety (secondary) of 3 concentrations of disperse blue 106 and 4 concentrations of bronopol in 40 adult subjects (20 subjects per allergen) with a clinical history of contact dermatitis and a positive patch test (current or previous) to the corresponding reference petrolatum allergen ("sensitives").

primary endpoint: to evaluate the diagnostic performance of disperse blue 106 and bronopol t.r.u.e. test allergens in 20 adult subjects per allergen with a clinical history of contact dermatitis and a positive patch test to the respective reference allergen. evaluations will include: * determination of the lowest concentration eliciting positive skin reactions (+1 or +2) in 70-90% of sensitive subjects. * frequency of positive, negative, doubtful and irritant reactions for each allergen and tested concentration. * concordance/discordance as compared to the corresponding reference petrolatum allergen. secondary endpoint: to evaluate the safety of disperse blue 106 and bronopol t.r.u.e. test allergens in 20 adult subjects per allergen with a clinical history of contact dermatitis and a positive patch test to the respective reference allergen. evaluations will include: * the frequency of tape-induced irritation at the test site, incomplete panel adhesion, and subject-reported sensations of itching or burning. * the frequency and characterization of adverse events and serious adverse events. * the frequency and characterization of late and/or persistent reactions.

Eligibility criteria:
inclusion criteria: * current or previous symptoms and/or history consistent with allergic contact dermatitis, and positive patch test (within the past 5 years) to bronopol or current or previous symptoms and/or history consistent with allergic contact dermatitis, and a positive patch test (within the past 5 years) to disperse blue 106 or disperse blue 106/124 allergen mix. * all subjects must be adults (18 years of age or older) and otherwise in good health. * premenopausal female subjects must consent to a urine pregnancy test; results must be negative for study inclusion. * informed consent must be signed and understood by each subject, and consistent with all institutional, local and national regulations. exclusion criteria: * subjects unable to meet inclusion requirements. * women who are breastfeeding or pregnant. * topical treatment during the last 7 days with corticosteroids or other immunosuppressive agents on or near the test area. * systemic treatment during the last 7 days with corticosteroids (equivalent to \> 10 mg prednisone) or other immunosuppressive agents. * treatment with ultraviolet (uv) light (including tanning) during the previous 3 weeks. * acute dermatitis outbreak or dermatitis on or near the test area on the back. * subjects unable to comply with patch test study requirements including multiple return visits and activity restrictions (e.g., protecting test panels from excess moisture due to showering or vigorous activity). * subject participation in clinical trials of investigational drugs, treatments or devices other than t.r.u.e. test during this study or 3 weeks prior to inclusion in this study.

Keywords: dermatitis, contact, bronopol, disperse blue 106