Background and importance Omalizumab is a monoclonal antibody with indication for chronic idiopathic urticaria (CIU). Adequate optimisation of omalizumab use could provide an improvement of efficiency in health systems without affecting the effectiveness of this therapy.

Aim and objectives To describe the effectiveness and efficiency data of an optimisation programme about use of omalizumab for CIU.

Material and methods A descriptive retrospective study was conducted. Patients with CIU included in a programme to optimise use of omalizumab until June 2021 were selected. The prescription softward program FarmaTools and electronic clinical history were used to record: duration of treatments, type of optimisation (dose reduction, therapy discontinuation or both), Urticaria Activity Score during a 7-day period (UAS7) and costs of therapies. Effectiveness of treatment was measured using UAS7 at 18 and 36 months. No response to therapy (NR) was defined as UAS7 >15. Mild disease (MD) presented UAS7 = 7–15. Adequate disease control (DC) was valued as UAS7 ≤6. Total response (TR) presented UAS7 =0. Patients with NR and presenting treatment suspension in a certain month were assumed to be NR in the following months. Optimisation of omalizumab treatment through treatment discontinuations or dose reduction was applied in patients with DC and TR. Regarding efficiency data, savings from the optimisation programme were estimated as the difference between costs of real omalizumab doses used in the optimisation programme and the hypothetical costs with the usual dose (300 mg/28 days).

Results There were 47 patients in the study. The median duration of therapy with omalizumab was 18 months. Optimisation of omalizumab treatment was performed in 61.7% of patients: 2.1% patients only presented dose reduction, 23.4% discontinuation of treatment and 36.2% of patients had both. At baseline, all patients presented NR (UAS7 >15). At 18 months, UAS7 data were: 20% of patients had NR, 16% MD, 8% DC and 56% TR. At 36 months, results of UAS7 were: 18.7% of patients presented NR, 6.3% MD, 31.3% DC and 43.7% TR. Total economic savings associated with optimisation of treatment with omalizumab were €286 150: €113 402 saved through dose reduction and €172 747 saved through therapy discontinuation.

Conclusion and relevance Our omalizumab optimisation programme for CIU provided high efficiency, maintaining nearly half of the patients with TR at 36 months.

References and/or acknowledgements None

Conflict of interest No conflict of interest