Decoy Therapeutics is trading at $2.01, down 5.63%; no clear catalyst was identified for the September 30 decline. - The company announced its CEO will present at The Small Cap Showcase on October 1; no link to the decline was established. - A September 29 preclinical update reported drug levels maintained in nasal and lung tissue for up to seven days; it does not explain the drop. - Major U.S. indexes were higher, so broad-market weakness does not appear to account for the drop.