Omalizumab in patients with allergic (IgE-mediated) asthma and IgE/bodyweight combinations above those in the initially approved dosing table.

Background: When first approved in the European Union (EU), the omalizumab dosing table had upper bodyweight and IgE limits of 150 kg and 700 IU/mL, respectively. In this study, we assessed the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of omalizumab in patients with IgE/bodyweight combinations above those in the original dosing table.

Methods: A multicentre, open-label, parallel-group study assessed the safety, PK and PD of omalizumab in 32 patients with mild-to-moderate allergic (IgE-mediated) asthma. Patients received two subcutaneous injections of omalizumab at one of three dosage levels (450, 525, or 600 mg), chosen according to baseline IgE (300-2000 IU/mL) and bodyweight (40-150 kg), with a 14-day interval between injections.

Results: Overall, 69 adverse events (AEs), none of them serious, were reported by 26 (81.3%) patients. Analysis of laboratory measurements, vital signs and ECG data revealed no adverse findings of clinical relevance. The PK profile was consistent with previous data for lower doses. Mean maximum decrease of free IgE from screening was ≥99% for all three doses, and mean free IgE concentrations remained <25 ng/mL for at least 2 weeks after the second dose. The reductions in free IgE were consistent with levels previously associated with clinical improvements.

Conclusions: The safety and PK/PD findings from this study are consistent with previous data, and supported the extension of the omalizumab dosing table to include those patients with higher IgE/bodyweight combinations. Clinical trial registry and registration number: clinicaltrials.gov (NCT00546143).