This was an open-label extension period of the previously randomized, multicenter, double-blind, placebo-controlled, parallel-group trial to demonstrate the benefit of pre- and co-seasonal combination therapy with anti-IgE (omalizumab) and specific immunotherapy (Depigoid) in patients with seasonal allergic asthma and co-morbid seasonal allergic rhinoconjunctivitis. During the open-label period, all patients received Depigoid monotherapy for two follow-up seasons every 4 weeks, 26 injections in total. The extension period was performed to evaluate the influence of omalizumab on the follow-up treatment with Depigoid in seasonal asthma.