In January 2006, Exubera® (Pfizer, New York, NY) became the first inhaled insulin to be approved by the U.S. Food and Drug Administration (FDA). However, Exubera was withdrawn from the market in 2007 due to low sales. Ongoing innovation in inhaled insulin led to FDA approval of Technosphere® Insulin (TI), the therapeutic component of the Afrezza® inhaled insulin delivery system (MannKind Corporation, Westlake Village, CA). Currently, TI is the only rapid-acting inhaled insulin currently available. Recent studies have demonstrated the efficacy of TI with no concerning adverse events other than mild cough, which is generally mild, transient, and diminishes over time. However, many clinicians remain cautious about the potential for adverse events with chronic use beyond the duration of closely monitored clinical trials. In this article, we address the pulmonary safety concerns that are often associated with TI and present evidence demonstrating the safety of TI in type 1 diabetes and type 2 diabetes populations.
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