Study to evaluate the Safety and Efficacy of CAT-354

Exclusion Criteria

• - Known history of allergy or reaction to any component of the investigational product formulation
• - Acute illness other than asthma at the start of the study
• - History of an active infection within 4 weeks prior to Screening, or evidence of clinically significant active infection, including ongoing chronic infection
• - History of ingestion of untreated water in a location known to be infected with parasites, resulting in acute or chronic diarrhea; or a diagnosis of parasitic infection within 6 months prior to Screening
• - Use of immunosuppressive medication (except oral prednisone up to 10 milligram/day (mg/day) and inhaled and topical corticosteroids) within 30 days before randomization into the study
• - Receipt of immunoglobulin or blood products within 30 days before randomization into the study
• - Receipt of any investigational drug therapy or use of any biologicals including omalizumab within 6 months before the first dose of investigational product in this study or within 5 half-lives of an investigational agent or biologic, whichever is longer
• - History of any known immunodeficiency disorder
• - A positive hepatitis B surface antigen, or hepatitis C virus antibody
• - A positive human immunodeficiency virus test or is taking antiretroviral medications, as determined by medical history and/or subject's verbal report
• - A live or attenuated vaccination received within 4 weeks prior to Screening
• - Previous medical history, or evidence, of an intercurrent illness that may compromise the safety of the subject in the study
• - History of clinically significant abnormality on electrocardiogram (ECG) in the opinion of the investigator
• - Lactation (women)
• - History of treatment for alcohol or drug abuse within the past year
• - History suggestive of chronic obstructive pulmonary disease (COPD) and of cigarette smoking >=10 pack-years
• - Evidence of any systemic disease on physical examination
• - History of cancer, apart from basal cell carcinoma or in situ carcinoma of the cervix treated with apparent success with curative therapy less than or equal to (<=)1 year prior to Study Day 1 or other malignancies treated with apparent success with curative therapy <=5 years prior to entry
• - Known exposure to inhaled occupational agents or fumes
• - Any condition (eg, cystic fibrosis [CF] or COPD) that, in the opinion of the investigator, would interfere with evaluation of the investigational product or interpretation of study results
• - Individuals who are legally institutionalized
• - Employees of the clinical study site or any other individuals involved with the conduct of the study, or family members of such individuals.