Background Omalizumab is used to treat poorly controlled, severe and immunoglobulin E (IgE) mediated asthma.

Purpose To check the appropriate prescribing practice, and to assess the effectiveness and safety of omalizumab.

Material and methods We conducted a retrospective study from January 2014 to August 2015, including all patients treated with omalizumab. They were followed-up for 16 and 32 weeks when possible. Variables included sex, age, weight, IgE level, omalizumab dose and other medication used before and after therapy, prick test of commercial allergens, volume exhaled during the first second of forced expiration (FEV₁ (%)), exhaled nitric oxide (FENO (ppb)), exacerbation needing oral corticosteroid use, hospital admissions, symptoms experienced during the day/night, adverse event due to omalizumab and concomitant diseases relevant for treatment outcomes.

ResultsDose of omalizumab was optimal according to the product information in 73.3% of patients. In 3 off-label cases, IgE level was too high. One patient was overweight.

Week 16 analysis showed that 75% (n = 3) of patients with high level exacerbations had recorded no events during this period, except one, who did not improve until week 32 (baseline IgE 5000 UI/mL). FEV₁ improved for 6 of 7 (85.7%) patients (Md 12; IQR 6.8–12,7; 95% CI -12.8 to 15.7). Moreover, IC, OC and LABA dose were reduced on 50%, 37.5% and 20%, respectively.

Week 32 information was available for only 2 patients.

Adverse events were observed in 30% of patients (hypotension, dyspnoea after the second dose which required treatment interruption, and check oppression).

Conclusion We observed good prescription adequacy and practice management for omalizumab, even if closer follow-up is necessary. Treatment was associated with a reduction in asthma exacerbations and IC, OC and LABA requirements in most patients, and it also showed an acceptable safety profile.

No conflict of interest.