Design of the FIBRONEER-ON open-label extension trial of nerandomilast (BI 1015550)

<bold>Background:</bold> There is a need for more effective treatments for idiopathic pulmonary fibrosis (IPF) and progressive pulmonary fibrosis (PPF). Nerandomilast (BI 1015550), an oral preferential inhibitor of PDE4B, is being evaluated in two randomised Phase III trials: FIBRONEER-IPF (<ext-link>NCT05321069</ext-link>) and FIBRONEER-ILD (<ext-link>NCT05321082</ext-link>). FIBRONEER-ON is an open-label extension (OLE) of these studies that will evaluate the long-term safety and efficacy of nerandomilast. <bold>Aims and objectives:</bold> To describe the design of the OLE. <bold>Methods:</bold> This prospective 2-year OLE will follow the Phase III parent trials. Approximately 1,700 patients from 44 countries are expected to complete the parent trials and will be eligible for continuing into the OLE. Whether previously on active treatment or placebo, all patients in the OLE will be treated with nerandomilast at either 9 mg or 18 mg twice daily, depending on which dose demonstrates the most favourable benefit–risk profile in the parent trial. <bold>Results:</bold> The primary endpoint will be the occurrence of any adverse event over the course of the OLE. This trial will also monitor long-term efficacy outcomes, including forced vital capacity change, and time to first exacerbation, disease progression, hospitalisation and death. <bold>Conclusions:</bold> This trial will provide information on the long-term safety, tolerability and efficacy of nerandomilast in patients with IPF and PPF. <fig><object-id>erj;64/suppl_68/PA672/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>