Severe persistent asthma responsive to off-label use of omalizumab despite high and low levels of total serum IgE Asma persistente grave com resposta ao uso off label de omalizumabe, não obstante a IgE sérica total ser alta ou baixa

Here, we present two cases of patients with severe persistent asthma. The two patients differed in terms of the total serum IgE level, which was quite high in one and quite low in the other. Despite the fact that the level of total serum IgE was not within the recommended range in either case, we opted to treat both with omalizumab. The treatment responses were favorable, and neither patient experienced any omalizumab-related side effects. The first case (Case 1) was in a 75-year-old woman who visited our hospital for an asthma evaluation. Her asthma had been poorly controlled despite multi-drug therapy with salmeterol (100 µg/day), fluticasone (1,000 µg/ day), ciclesonide (200 µg/day), tiotropium (18 µg/day), montelukast (10 mg/day), fexofenadine (60 mg/day), and theophylline (200 mg/day). As can be seen in Table 1, she had an asthma control test (ACT) score of 7 at the initial evaluation. The total serum IgE level was 1,149 IU/mL, and she tested positive for specific IgE to house dust and mites. In the previous year, she had had numerous asthma exacerbations, resulting in 7 emergency room visits and 6 hospitalizations. With the consent of the patient, we decided to initiate treatment with omalizumab, despite the fact that her total serum IgE level was well above the recommended cut-off value of 700. Omalizumab (300 mg/kg of body weight) was administered every two weeks for 16 weeks. The dose was determined to be identical to that which would be given based on the high IgE level. The patient reported an improvement in her quality of life immediately (after the first dose), and her ACT score rose to 25 (the maximum score). There were also improvements in PEF and FEV 1 (Table 2). We therefore classified the patient as an omalizumab responder, and the treatment was characterized as definitely effective. Thereafter, we maintained her on omalizumab (150 mg/ kg every 4 weeks). While under treatment with