Montrevel En Bresse

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 remain on study for a period of time as based on regulatory region. 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.