The rates of hospitalization and serious infection between psoriasis patients treated with ustekinumab (N = 2,301) and those from a U.S. health care claims database (N = 1,183) were compared. Rates of hospitalization and serious infection were 11.3 and 2.2 cases/100 patient-years, respectively, from the claims database. The corresponding values from patients treated with ustekinumab were 4.8 and 1.01/100 patient-years, respectively. The expected rates adjusted for age and gender distribution were 7.21 and 1.49 cases/100 patient-years, respectively. Thus these rates in ustekinumab-treated patients were consistent with expected rates in general subjects with psoriasis from the claims database (Healy, E. et al. Br J Dermatol 2009, 161(Suppl. 1): 27, Abst P-15).