Omalizumab for Idiopathic Nonhistaminergic Angioedema:Evidence for Efficacy in 2 Patients

Presently, there is inconclusive evidence regarding the most effective treatment for idiopathic nonhistaminergic acquiredangioedema (InH-AAE). Omalizumab may, however, prove to be a promising option. This case report describes two patientswho presented with recurrent angioedema attacks, which was refractory to antihistamine therapy. Hence, they were treated with300 mg omalizumab, every 4 weeks, for a period of 6 months. Both patients had shown a rapid response to the treatment andachieved complete resolution of symptoms without further AE attacks throughout the entire duration of the treatment period. Afteromalizumab’s suspension, one patient remained symptom free for the following 6 months and the other patient had recurrence ofsymptoms after 2 months for which he was retreated with omalizumab and once again became symptom free. Although omalizumabseems to be effective as a prophylactic treatment for InH-AAE, the determining factors leading to the differences in time-to-relapse between patients after its suspension remain unclear. Further studies are needed in order to better determine the potentialtherapeutic application of omalizumab and its role in maintenance therapy.