Targeted Therapy Using Intradermal Injection of Etanercept for Remission Induction in Discoid Lupus Erythematosus

There is an unmet need for new therapies to control inflammation in discoid lupus erythematosus (DLE). A significant proportion of DLE patients (with or without systemic lupus erythematosus (SLE)) are resistant to conventional therapies and DLE may be exacerbated by B cell depletion therapy.There is no clinical guideline or algorithm on how to manage patients with DLE who have refractory disease to the first line agents, anti-malarials. If left untreated, uncontrolled inflammation will lead to permanent disfiguring and irreversible scar to the patient, thus pose a major cosmetic issue and significantly impair the quality of life. Targeted therapy based on immunopathogenesis is an attractive approach and tumour necrosis factor (TNF) is implicated in the pathogenesis of DLE. However, systemic administration of TNF blockers has been associated with induction of pathogenic autoantibodies that may render SLE worse or progression from DLE only to SLE. TNF blockers have been administered using the intra-dermal injection route in other TNF-mediated diseases and appear similarly safe and effective to systemic administration. Another issue is the problem with outcome measures as skin disease is particularly heterogenous and many instruments rely on subjective assessment which may be difficult even in the hands of experts. The TARGET-DLE trial will address these problems by: (i) administering a TNF blocker, etanercept using the intra-dermal route, which will provide local concentration to neutralise TNF in tissue while minimises the effect to systemic immunity and (ii) measuring tissue response using the existing outcome measure; the modified limited Score of Activity and Damage in DLE (SADDLE) as well as new objective measures such as skin biopsy, optical coherence tomography (OCT), thermography and laser Doppler imaging (LDI). Data from this study may be used to power a definitive randomised controlled trial should the primary end point be achieved.