An Extension Study of Subjects Who Received an Avalyn Inhaled Antifibrotic Agent (SAIL)

All participants will receive 100 mg inhaled pirfenidone inhalation solution (AP01) taken twice daily using the eFlow Nebulizer System. The study will consist of a Screening/Baseline Visit, an open-label Treatment Period, and a Follow-up/End of Study (EOS) phone call. During the open-label Treatment Period, subjects will receive study drug (AP01 from their lead-in study). Subjects will complete an EOS follow-up phone call approximately 2 weeks after their last dose of study drug. A paper dosing diary will be used to monitor adherence along with returns of any unused investigational product.