Anti-TSLP (AMG 157) Plus Antigen-Specific Immunotherapy for Induction of Tolerance in Individuals With Cat Allergy

Inclusion Criteria: * History of moderate-severe allergic rhinitis caused by cat exposure for at least 2 yrs * Skin prick test wheal \>/=5 mm to standardized cat extract * Immunoglobulin E (IgE) \>/=0.7 kU/L (class 2) to cat extract * Screening nasal allergen challenge in which: \*TNSS is \</= 3 after the 0 concentration (vehicle control only) dose, * TNSS increase is \</=1 from the TNSS prior to allergen administration to the TNSS after the 0 concentration (vehicle control only) dose, * TNSS is \>/=8 after the highest dose, and * Between the first non-zero dose and 10 minutes after the highest dose,either: * \>/=3 sneezes are counted or * \>20% drop in PNIF is recorded * Body mass index (BMI) between 1 and 32 kg/m\^2, inclusive at screening * Clinically acceptable physical examination and electrocardiogram (ECG) results (12-lead reporting RR, PR, QRS, QT and QTcF) prior to Day 0 based on the opinion of the investigator * Adequate renal function (defined by creatinine clearance \>80 mL/min using the Cockcroft Gault equation) * For women of childbearing age, a willingness to use a highly effective form of contraception for five months after last dose of study medication. Highly effective methods of birth control include abstinence, vasectomy by the male partner, or a condom with spermicide in combination with either hormonal birth control, IUD or barrier methods used by the woman. * For men with female partners of childbearing potential, agreement not to donate sperm …