Octreotide treatment of idiopathic pulmonary fibrosis: a proof-of-concept study

To the Editors: Idiopathic pulmonary fibrosis (IPF) is the most frequent form of idiopathic interstitial pneumonia. It is a chronic, progressive and fatal disease of unknown aetiology, characterised by histological features of usual interstitial pneumonia (UIP). Disease progression is marked by worsening dyspnoea, progressive loss of lung volume, abnormal gas exchange and poor quality of life. Median survival after diagnosis is 3–5 yrs. Currently, pirfenidone is the only drug approved in Europe for the treatment in IPF, as it has been shown to slow the decline of lung function [1]. However, no effect on survival has been demonstrated until now. Somatostatin is an endogenous cyclic peptide initially identified as a regulator of growth hormone secretion. In humans, it has been shown to bind with equal efficiency to five receptors: sst1, sst2A, sst3, sst4 and sst5. We have recently shown that the sst2A receptor is highly expressed in fibrotic lung tissue in IPF patients and that the uptake of octreotide, a somatostatin analogue that has a high affinity for sst2A, is elevated in the lungs of IPF patients and is correlated with the severity of lung fibrosis [2, 3]. Octreotide has been widely used for the treatment of neuroendocrine tumours for >20 yrs. In this study, we investigated the safety and efficacy of octreotide as a therapy for IPF. This was an open-label, proof-of-concept, non-randomised, non-controlled, multicentre phase II study performed in France between October 2006 and April 2008 to evaluate the safety and efficacy of intramuscular long-acting octreotide in patients with IPF. The trial was registered with ClinicalTrials.gov (identifier number NCT00463983). Patients had to be aged ≥40 yrs and meet the diagnostic criteria for IPF described in the American Thoracic Society/European Respiratory Society consensus statement [4]. In patients aged <50 yrs, a …