Real-life effectiveness of omalizumab in severe allergic asthma above the recommended dosing range criteria

Abstract

BACKGROUND: Omalizumab (Xolair) dosing in severe allergic asthma is based on serum IgE and bodyweight. In Australia, patients eligible for omalizumab but exceeding recommended ranges for IgE (30-1500 IU/mL) and bodyweight (30-150 kg) may still receive a ceiling dose of 750 mg/4 weeks. About 62% of patients receiving government-subsidized omalizumab are enrolled in the Australian Xolair Registry (AXR).OBJECTIVES: To determine whether AXR participants above the recommended dosing ranges benefit from omalizumab and to compare their response to within-range participants. <br />METHODS: Data were stratified according to dose range status (above-range or within-range). Further sub-analyses were conducted according to the reason for being above the dosing range (IgE only vs. IgE and weight). <br />RESULTS: Data for 179 participants were analysed. About 55 (31%) were above recommended dosing criteria; other characteristics were similar to within-range participants. Above-range participants had higher baseline IgE [812 (IQR 632, 1747) IU/mL vs. 209 (IQR 134, 306) IU/mL] and received higher doses of omalizumab [750 (IQR 650, 750) mg] compared to within-range participants [450 (IQR, 300, 600) mg]. At 6 months, improvements in Juniper 5-item Asthma Control Questionnaire (ACQ-5, 3.61 down to 2.01 for above-range, 3.47 down to 1.93 for within-range, P < 0.0001 for both) and Asthma Quality of Life Questionnaire (AQLQ mean score (3.22 up to 4.41 for above-range, 3.71 up to 4.88 for within-range, P < 0.0001) were observed in both groups. Forced expiratory volume in one second (FEV1 ) improved among above-range participants. There was no difference in response between above-range and within-range participants. Above-range participants due to either IgE alone or IgE and weight had similar improvements in ACQ-5, AQLQ and FEV1 . <br />CONCLUSIONS AND CLINICAL RELEVANCE: Patients with severe allergic asthma above recommended dosing criteria for omalizumab have significantly improved symptom control, quality of life and lung function to a similar degree to within-range participants, achieved without dose escalation above 750 mg.Copyright © 2016 John Wiley & Sons Ltd. <br />Hew, MGillman, A <br />Sutherland, M <br />Wark, P <br />Bowden, J <br />Guo, M <br />Reddel, H K <br />Jenkins, C <br />Marks, G B <br />Thien, F <br />Rimmer, J <br />Katsoulotos, G P <br />Cook, M <br />Yang, I <br />Katelaris, C <br />Bowler, S <br />Langton, D <br />Wright, C <br />Bint, M <br />Yozghatlian, V <br />Burgess, S <br />Sivakumaran, P <br />Yan, K Y <br />Kritikos, V <br />Peters, M <br />Baraket, M <br />Aminazad, A <br />Robinson, P <br />Jaffe, A <br />Powell, H <br />Upham, J W <br />McDonald, V M <br />Gibson, P G <br />