BACKGROUND

Discoid lupus erythematosus (DLE) is a chronic form of cutaneous lupus, which can cause scarring. Many drugs have been used to treat this disease and some (such as thalidomide, cyclophosphamide and azathioprine) are potentially toxic. This is an update of a Cochrane Review first published in 2000, and previously updated in 2009. We wanted to update the review to assess whether any new information was available to treat DLE, as we were still unsure of the effectiveness of available drugs and how to select the most appropriate treatment for an individual with DLE.

OBJECTIVES

To assess the effects of drugs for discoid lupus erythematosus.

SEARCH METHODS

We updated our searches of the following databases to 22 September 2016: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase and LILACS. We also searched five trials databases, and checked the reference lists of included studies for further references to relevant trials. Index Medicus (1956 to 1966) was handsearched and we approached authors for information about unpublished trials.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) of drugs to treat people with DLE in any population group and of either gender. Comparisons included any drug used for DLE against either another drug or against placebo cream. We excluded laser treatment, surgery, phototherapy, other forms of physical therapy, and photoprotection as we did not consider them drug treatments.

DATA COLLECTION AND ANALYSIS

At least two reviewers independently extracted data onto a data extraction sheet, resolving disagreements by discussion. We used standard methods to assess risk of bias, as expected by Cochrane.

MAIN RESULTS

Five trials involving 197 participants were included. Three new trials were included in this update. None of the five trials were of high quality.'Risk of bias' assessments identified potential sources of bias in each study. One study used an inappropriate randomisation method, and incomplete outcome data were a concern in another as 15 people did not complete the trial. We found most of the trials to be at low risk in terms of blinding, but three of the five did not describe allocation concealment.The included trials inadequately addressed the primary outcome measures of this review (percentage with complete resolution of skin lesions, percentage with clearing of erythema in at least 50% of lesions, and improvement in patient satisfaction/quality of life measures).One study of fluocinonide cream 0.05% (potent steroid) compared with hydrocortisone cream 1% (low-potency steroid) in 78 people reported complete resolution of skin lesions in 27% (10/37) of participants in the fluocinonide cream group and in 10% (4/41) in the hydrocortisone group, giving a 17% absolute benefit in favour of fluocinonide (risk ratio (RR) 2.77, 95% CI 0.95 to 8.08, 1 study, n = 78, low-quality evidence). The other primary outcome measures were not reported. Adverse events did not require discontinuation of the drug. Skin irritation occurred in three people using hydrocortisone, and one person developed acne. Burning occurred in two people using fluocinonide (moderate-quality evidence).A comparative trial of two oral agents, acitretin (50 mg daily) and hydroxychloroquine (400 mg daily), reported two of the outcomes of interest: complete resolution was seen in 13 of 28 participants (46%) on acitretin and 15 of 30 participants (50%) on hydoxychloroquine (RR 0.93, 95% CI 0.54 to 1.59, 1 study, n = 58, low-quality evidence). Clearing of erythema in at least 50% of lesions was reported in 10 of 24 participants (42%) on acitretin and 17 of 25 (68%) on hydroxychloroquine (RR 0.61, 95% CI 0.36 to 1.06, 1 study, n = 49, low-quality evidence). This comparison did not assess improvement in patient satisfaction/quality of life measures. Participants taking acitretin showed a small increase in serum triglyceride, not sufficient to require withdrawal of the drug. The main adverse effects were dry lips (93% of the acitretin group and 20% of the hydroxychloroquine group) and gastrointestinal disturbance (11% of the acitretin group and 17% of the hydroxychloroquine group). Four participants on acitretin withdrew due to gastrointestinal events or dry lips (moderate-quality evidence).One trial randomised 10 people with DLE to apply a calcineurin inhibitor, pimecrolimus 1% cream, or a potent steroid, betamethasone 17-valerate 0.1% cream, for eight weeks. The study reported none of the primary outcome measures, nor did it present data on adverse events.A trial of calcineurin inhibitors compared tacrolimus cream 0.1% with placebo (vehicle) over 12 weeks in 14 people, but reported none of our primary outcome measures. In the tacrolimus group, five participants complained of slight burning and itching, and for one participant, a herpes simplex infection was reactivated (moderate-quality evidence).Topical R-salbutamol 0.5% cream was compared with placebo (vehicle) over eight weeks in one trial of 37 people with DLE. There was a significant improvement in pain and itch in the salbutamol group at two, four, six, and eight weeks compared to placebo, but the trial did not record a formal measure of quality of life. None of the primary outcome measures were reported. Changes in erythema did not show benefit of salbutamol over placebo, but we could not obtain from the trial report the number of participants with clearing of erythema in at least 50% of lesions. There were 15 events in the placebo group (experienced by 12 participants) and 24 in the salbutamol group (experienced by nine participants). None of the adverse events were considered serious (moderate-quality evidence).

AUTHORS' CONCLUSIONS: Fluocinonide cream may be more effective than hydrocortisone in clearing DLE skin lesions. Hydroxychloroquine and acitretin appear to be of equal efficacy in terms of complete resolution, although adverse effects might be more frequent with acitretin, and clearing of erythema in at least 50% of lesions occurred less often in participants applying acitretin. Moderate-quality evidence found adverse events were minor on the whole. There is not enough reliable evidence about other drugs used to treat DLE. Overall, the quality of the trials and levels of uncertainty were such that there is a need for further trials of sufficient duration comparing, in particular, topical steroids with other agents.