Pulmonary exposure to chemical warfare agents (CWA), or to industrial pulmonary toxicants (IPT) is a serious unmet medical challenge that impacts the safety of our nation’s civilian population and armed forces that could result in high morbidity and mortality. Effective medical countermeasures (MCM) are not available to treat pulmonary exposure to CWA or to IPT that threaten the lives of civilians and military personnel. We have developed XFB19, a first-in-class, homeostatic, direct anti-inflammatory, anti-fibrotic interference peptide against the Thr266 phosphorylation site of human C/EBPβ, with outstanding efficacy in models of CWA (sulfur mustard), Acute Respiratory Distress Syndrome (sulfur mustard, bleomycin), and Idiopathic Pulmonary Fibrosis (bleomycin). XFB19 has an excellent safety and efficacy profile in pre-clinical studies. The Aims of this SBIR Direct to Phase 2 will facilitate the development of XFB19 as an MCM for pulmonary toxicants, as well as a treatment for Acute Respiratory Distress Syndrome and Idiopathic Pulmonary Fibrosis.