New Inhaled Formulation of Pirfenidone Shows Promise for Idiopathic Pulmonary Fibrosis Patients, with Fewer Side Effects
Treatment with AP01, an experimental inhaled formulation of pirfenidone developed by Avalyn Pharma, is proving to be slightly more effective for idiopathic pulmonary fibrosis (IPF) patients compared to the oral version, Esbriet. Additionally, AP01 results in fewer side effects. These findings were presented at the European Respiratory Society (ERS) International Congress 2023 in Milan.
The Phase 1b ATLAS clinical trial and its open-label extension study, AP01-005, showed that AP01 demonstrated better efficacy and safety profiles compared to Ofev, the only approved therapy for progressive forms of pulmonary fibrosis (PPF). Dr. Howard M. Lazarus, Avalyn’s chief medical officer, stated that the consistent trend toward lung function stabilization across these studies indicates that AP01 is reaching the lungs with sufficient concentrations and having the intended effect in both idiopathic and progressive forms of pulmonary fibrosis.
The standard of care for IPF is pirfenidone, which works to slow the progression of lung scarring, the characteristic feature of pulmonary fibrosis. Esbriet, an oral formulation of pirfenidone, is commonly prescribed for IPF. However, it is associated with gastrointestinal side effects that may be intolerable for some patients. Avalyn’s AP01 is delivered directly to the lungs via a soft mist nebulizer, allowing for lower doses and potentially reducing the risk of side effects associated with whole-body exposure.
The ATLAS trial enrolled 91 adults with IPF who were intolerant to or ineligible for Esbriet or Ofev. Participants received either a 50 mg once daily dose or a 100 mg twice daily dose. After about six months, all patients still in the trial transitioned to the higher dose until week 72. Most patients treated with the higher dose experienced stable lung function at six months and one year of treatment.
The subsequent AP01-005 extension study included 41 IPF patients from the ATLAS trial, as well as additional participants who had not previously participated in an AP01 trial. Interim data from the extension study showed slower Forced Vital Capacity (FVC) decline in both the IPF and PPF patients compared to those treated with Esbriet and Ofev. AP01 was also associated with lower rates of side effects such as nausea, rash, diarrhea, indigestion, and vomiting, in comparison to Esbriet and Ofev.
Avalyn plans to launch a Phase 2 trial of AP01 in PPF patients, with recruitment beginning early next year. With these promising results, the company expects to continue the clinical development of AP01 for the treatment of various fibrotic lung diseases.