A Phase 1, randomized, placebo-controlled, dose-escalation study to evaluate the safety and tolerability of ascending single subcutaneous and intravenous doses of MEDI4212 in subjects with immunoglobulin E (IgE) greater than or equal to (>=) 30 international units per milliliters (IU/mL).
Phase 1 study to evaluate the safety of MEDI4212.