This is a multi-center, randomized, single-blind*, parallel group, placebo-controlled, study with two dosing regimens in subjects diagnosed with moderate to severe asthma using MN-221 or placebo. Subjects will be randomized to receive MN-221 or placebo in a 3:1 ratio, MN-221:placebo. Subjects randomized to receive MN-221 will be dosed with active study drug at both dosing visits, and subjects randomized to the placebo arm will receive placebo at both dosing visits. Approximately 25 subjects diagnosed with moderate to severe asthma who have not received inhaled corticosteroid therapy within one month of Screen Visit 1 will be enrolled and will participate throughout the study.