Inhaled aviptadil for the possible treatment of COVID-19 in patients at high risk for ARDS: study protocol for a randomized, placebo-controlled, and multicenter trial oleh Maria Boesing, Kristin Abig, Michael Brändle, Martin Brutsche, Emanuel Burri, Björn C. Frye, Stéphanie Giezendanner, Jan C. Grutters, Philippe Haas, Justian Heisler, Fabienne Jaun, Anne B. Leuppi-Taegtmeyer, Giorgia Lüthi-Corridori, Joachim Müller-Quernheim, Reto Nüesch, Wolfgang Pohl, Frank Rassouli, Jörg D. Leuppi