OBJECTIVES: To perform a cost-effectiveness analysis of treatment sequences that include dimethyl fumarate (DMF) prior to biological therapies in adult patients with moderate-to-severe plaque psoriasis in need of systemic therapy, from both a payer (National Health Service, NHS) and social perspective in the UK.

METHODS: A Markov state-transition cohort model was developed with a 14-day treatment cycle and 10-year horizon to evaluate oral DMF as an addition to the standard treatment sequence prior to biological therapies (i.e. prior to adalimumab and ustekinumab), followed by best supportive care. In the comparator sequence, patients did not receive DMF prior to the standard treatment with biological therapies. Two health states were included in the model: a trial (10–16 weeks) and a maintenance period. Responders (patients who achieved a Psoriasis Area and Severity Index reduction of 75% [PASI 75]) continued with treatment; non-responders moved to subsequent lines of therapy. Data from published studies and a network meta-analysis provided health utilities and other model inputs. Outputs of the model included quality-adjusted life years (QALYs), incremental cost-effectiveness ratios and costs per patient. Scenario analyses were used to evaluate model inputs of discount rates, gender, age, withdrawal rate and baseline health utilities. Sensitivity analyses were performed to determine robustness of the model.

RESULTS: In the base case analysis, cost and QALY data indicated dominance of the DMF treatment sequence vs the comparator sequence, with a saving of £384 per patient, coupled with a gain in QALY when using the DMF treatment sequence (7.10 vs 7.07). Across all scenarios tested, the introduction of DMF represented a cost-effective option (mean probability: 97%) at the £20,000 per QALY willingness-to-pay threshold.

CONCLUSIONS: The introduction of DMF prior to biological agents is a dominant treatment strategy for the treatment of moderate-to-severe psoriasis in the UK.