Cysteamine for Asthma

Asthma affects 25.7 million people in the US. Many people report symptoms despite taking high-doses of inhaled asthma medications. This difficult-to-treat group accounts for more than 50% of asthma related healthcare visits and hospitalizations. The purpose of this study is to see if a medicine called Cysteamine, given along with standard asthma care, will improve asthma symptoms and lung function. This study is a double-blind, placebo-controlled, randomized trial of cysteamine. A placebo arm will be included to determine the comparative effectiveness of cysteamine in this population. Eligible participants will be assessed 1, 4 and 8 weeks post randomization and followed for an additional 4 weeks post treatment. In order to enroll in this study, participants must be between the ages of 18-45 and have uncontrolled asthma. This study will include 4 visits and weekly phone calls, and will be in the study for 3-4 months. During the treatment period, participants will be placed in one of two treatment groups: * Cysteamine * Placebo Participants will not be able to choose which group they are assigned. This assignment is random and by chance, much like flipping a coin. Participants will not know if they are receiving Cysteamine or placebo. Investigators will compare the study results between the participants of each group.