A Study of Lebrikizumab (RO5490255) in Participants With Severe Oral Corticosteroids (OCS) Dependent Asthma

This randomized, multicenter, double-blind, placebo-controlled, parallel-group study will evaluate the efficacy of lebrikizumab compared with placebo, as measured by the ability of participants to achieve lower daily doses of OCS, among those with severe corticosteroid-dependent asthma. Prednisone/prednisolone will be the OCS therapy prescribed. Participants will be randomized to receive lebrikizumab or matching placebo for 44 weeks in a double-blind, placebo-controlled (DBPC) period. Those who complete the 44-week period may continue into a 32-week active treatment extension (ATE) period, during which all participants will receive lebrikizumab treatment. Following completion of the ATE period, participants who have both tolerated and derived benefit from treatment with lebrikizumab may continue their lebrikizumab treatment into a long-term extension (LTE) period. Participants will transition to 24 weeks of safety follow-up upon discontinuation of study drug.