Dupilumab (anti-IL-4Rα) shows overall better efficacy than other biologics in treating severe eosinophilic asthma. However, hyper eosinophilia has been observed in some patients with some experiencing severe side effects, including those resistant to anti-IL-5/IL-5Rα agents. Mepolizumab (anti-IL-5), which blocks the IL-5/IL-5Rα pathway could inhibit IL-5-mediated eosinophil differentiation and expansion, amd results in a rapid and robust reduction of blood and sputum eosinophil counts. PM1017 is a bispecific antibody Fc-silencing and half -life extension, which targets IL-4Rα and IL-5 simultaneously. This design provides a potential larger effect through the concomitant modulation of both pathways.