Doxycycline compared with prednisolone therapy for patients with bullous pemphigoid: cost-effectiveness analysis of the BLISTER trial

Background : Bullous pemphigoid (BP) is an autoimmune blistering skin disorder associated with significant morbidity and mortality. Doxycycline and prednisolone to treat bullous pemphigoid were compared within a randomized controlled trial (RCT). Objectives : To compare the cost-effectiveness of doxycycline-initiated and prednisolone-initiated treatment for patients with BP. Methods : Quality-of-life (EuroQoL-5D-3L) and resource data were collected as part of the BLISTER trial: a multicentre, parallel-group, investigator-blinded RCT. Within-trial analysis was performed using bivariate regression of costs and quality-adjusted life-years (QALYs), with multiple imputation of missing data, informing a probabilistic assessment of incremental treatment cost-effectiveness from a health service perspective. Results : In the base case, there was no robust difference in costs or QALYs per patient at 1 year comparing doxycycline- with prednisolone-initiated therapy [net cost £959, 95% confidence interval (CI) −£24 to £1941; net QALYs −0·024, 95% CI −0·088 to 0·041]. However, the findings varied by baseline blister severity. For patients with mild or moderate blistering (≤ 30 blisters) net costs and outcomes were similar. For patients with severe blistering (> 30 blisters) net costs were higher (£2558, 95% CI −£82 to £5198) and quality of life poorer (−0·090 QALYs, 95% CI −0·22 to 0·042) for patients starting on doxycycline. The probability that doxycycline would be cost-effective for those with severe pemphigoid was 1·5% at a willingness to pay of £20 000 per QALY. Conclusions : Consistently with the clinical findings of the BLISTER trial, patients with mild or moderate blistering should receive treatment guided by the safety and effectiveness of the drugs and patient preference – neither strategy is clearly a preferred use of National Health Service resources. However, prednisolone-initiated treatment may be more cost-effective for patients with severe blistering.