According to the results of an international, single-arm, open-label, phase 4 study published in the European Respiratory Journal, combination therapy with pirfenidone and nintedanib was safe and tolerated by the majority of patients with idiopathic pulmonary fibrosis (IPF).

Both pirfenidone and nintedanib have shown efficacy and have been approved as monotherapy for IPF, and both agents received conditional recommendation for use in IPF in the 2015 update of the American Thoracic Society (ATS)/European Respiratory Society (ERS)/Japanese Respiratory Society (JRS)/Latin American Thoracic Association (ALAT) clinical practice guidelines.

However, neither agent stops or reverses the disease. As it is believed that these agents have differing mechanisms of action, with evidence suggesting that they may target different aspects of the fibrotic cascade involved in IPF, it has been suggested that combination therapy may benefit patients with IPF.