Cost-effectiveness of the two-compound formulation calcipotriol and betamethasone dipropionate compared with commonly used topical treatments in the management of moderately severe plaque psoriasis in Scotland.
OBJECTIVE
To determine the cost-effectiveness of calcipotriol/betamethasone dipropionate (Dovobet) in the initial treatment of moderate severity plaque psoriasis vulgaris in Scotland.


METHODS
An economic model was developed to simulate the costs and benefits of the most commonly used topicals in the management of plaque psoriasis. This was informed by an indirect unadjusted comparison of the effectiveness data to determine the relative efficacy of commonly used topicals. The model estimated their impact on costs and utility gain over a 1-year period. We accounted for direct medical costs from a health payer perspective. The cost-utility analysis included pharmacy costs and costs of failure of topicals in primary care in terms of secondary-care referrals for phototherapy. Extensive sensitivity analyses were undertaken to address areas of uncertainty in the parameters of the model.


RESULTS
Patients treated with the two-compound formulation (TCF) of calcipotriol and betamethasone dipropionate (BDP) experienced better control of their psoriasis. In our model, this translated into reduced costs, as patients were less likely to be referred for phototherapy, and increased quality adjusted life years (QALYs) relative to other commonly used topicals. The TCF was estimated to generate annual savings ranging from 96 to 276 pounds per patient per year compared to the other commonly used alternative topicals. With reduced costs and superior outcomes, the TCF 'dominated' these other treatments since the latter were associated with higher cost and lower utility or QALY gain. The model findings were not influenced by changes to a range of model input parameters within plausible limits.


CONCLUSIONS
Use of the TCF in patients with plaque psoriasis represents excellent value for money by delivering savings to the National Health Service (NHS) in Scotland. Similar findings are predicted for the management of psoriasis patients elsewhere in the UK.
Bottomley
Julia M
JM
Amygdala Ltd, Letchworth Garden City, UK. jmb@amygdala.uk.com <jmb@amygdala.uk.com>
Auland
Merran E
ME
Morais
Jeremy
J
Boyd
Gordon
G
Douglas
W Stewart
WS
D000287:Administration, Topical; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001623:Betamethasone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D002117:Calcitriol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D003879:Dermatologic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D004338:Drug Combinations; D006801:Humans; D011565:Psoriasis / Q000188:drug therapy*; D019057:Quality-Adjusted Life Years; D012606:Scotland; D013222:State Medicine; D016896:Treatment Outcome
D000893:Anti-Inflammatory Agents; D003879:Dermatologic Agents; D004338:Drug Combinations; C055085:calcipotriene; C011175:betamethasone-17,21-dipropionate; D001623:Betamethasone; D002117:Calcitriol