OBJECTIVES: Chronic spontaneous urticaria (CSU) is a skin disease, with itchy hives and/or angioedema which last for at least 6 weeks without obvious causes. Omalizumab is a humanized anti-IgE recombinant monoclonal antibody that has shown good efficacy and safety in treatment of Chinese CSU patients inadequately controlled by H1-antihistamines from Phase III clinical study (CIGE025E2305). The objective was to estimate the cost effectiveness of Omalizumab combined with H1-antihistamines treatment compared to placebo and H1-antihistamines in patients with moderate or severe CSU from the perspective of Chinese medical service system.

METHODS: A Markov model of 10 years’ time horizon was developed to estimate direct costs and outcomes associated with 3-month courses of Omalizumab (150mg/month) initial treatment and retreatment upon relapse. The structure of the model was defined by five disease activity health states (free, well controlled, mild, moderate, severe) based on Urticaria Activity Score over 7 days (UAS7) scores and three additional states (relapse, spontaneous remission and death). The inputs of transition probability, direct costs, health utilities were derived from Chinese Phase III study, Chinese CSU disease burden study and published literature respectively.

RESULTS: In the base case analysis, the incremental outcomes for Omalizumab combined with H1-antihistamines treatment were 0.239 QALYs and incremental direct costs were ¥5487 compared with placebo and H1-antihistamines , corresponding to an ICER of ¥22950/QALY which was less than the preset willingness-to-pay threshold (1 time GDP per capita in China:¥81,000). One-way sensitivity analysis showed that the utility made greater influence on the result than price of Omalizumab and other parameters. Probabilistic sensitivity analyses confirmed the robustness of the model results, the probability of Omalizumab combined with H1-antihistamines treatment being cost-effective was 84% at the willingness-to-pay threshold.

CONCLUSIONS: 3-month courses of Omalizumab (150mg/month) can be considered as a cost-effective option in the treatment of CSU in China.