Enterprise Therapeutics Ltd. (Enterprise), a biopharmaceutical company dedicated to discovering and developing new treatments to improve the lives of people with respiratory diseases, today announced that a Phase 2 study of ETD001, the company’s lead candidate for the treatment of cystic fibrosis (CF), achieved key efficacy results. This study aimed to investigate the efficacy, safety, tolerability, and pharmacokinetics of inhaled ETD001 in the 10% of patients with CF (pwCF) who do not benefit from treatment with CFTR modulators and have the highest unmet medical need. Data from this trial showed improved lung function over 28 days compared to placebo.
ETD001 is an investigational inhaled epithelial sodium channel (ENaC) blocker designed to enhance lung function by improving mucus clearance and reducing airway obstruction. Study data demonstrate a 3.4 percentage point (p-value = 0.0053) difference in percent predicted forced expiratory volume in 1 second (ppFEV1) in pwCF when treated with ETD001 compared to placebo. Exploratory analysis showed that participants were three times more likely to have improved ppFEV1, and therefore lung function, when given ETD001 compared to placebo. The results also show that ETD001 was overall well tolerated in pwCF, with adverse events consistent with those expected in this study population of pwCF receiving inhaled drugs.
The trial was split into two parts and conducted at sites in the UK, Germany, France, and Italy with pwCF who were not eligible for or had not received CFTR modulators. Part A evaluated the safety and tolerability of repeated inhalation administration of ETD001 over 7 days through monitoring for adverse events. Part B used a double-blind, placebo-controlled crossover design to examine the effect of BID repeated dosing (twice daily) of ETD001 (4.5 mg) over 28 days on the absolute change in ppFEV1. Participants were randomly assigned to receive either placebo or ETD001 for 28 days in a two-group, two-sequence crossover design with a 28-day washout period. Results from this clinical trial (NCT06478706) will be presented at the European Cystic Fibrosis Society Congress in Lisbon in June (www.ecfs.eu/lisbon2026).
Enterprise plans to proceed to a longer Phase 2b dose-ranging study in pwCF to evaluate the efficacy of ETD001 in addition to CFTR modulators. Due to the overwhelming evidence that non-CF bronchiectasis patients also suffer from high mucus volume and mucus congestion, Enterprise plans to initiate further clinical trials in this patient population.
We are pleased to see the positive results of the Phase 2 study for ETD001. These data demonstrate that this novel inhaled ENaC blocker was well tolerated in pwCF and showed improved lung function over 28 days compared to placebo. We are encouraged by the potential of ETD001 to become a new treatment option to improve the lives of all pwCF, especially those for whom there are currently no effective treatments, and we are grateful to everyone who participated in this study. ”
Dr. Renu Gupta, CMO, Enterprise Therapeutics
Dr. Martin Gosling, CSO, Enterprise Therapeutics, commented:The data from this trial represent an important milestone as it is the first time that an ENaC blocker has demonstrated efficacy in pwCF. We are hopeful that these data will enhance treatment options for all pwCF and potentially extend to other mucosal obstructive pulmonary diseases, including bronchiectasis. Observing improvements in lung function within 28 days of treatment with ETD001 was an important milestone and we now look forward to moving forward into longer-term clinical trials where further clinical efficacy is expected.. ”
Dr. John Ford, CEO of Enterprise Therapeutics, added:We would like to thank everyone involved in the development of the ETD001 program to this stage. It’s really encouraging to see the results of this Phase 2 trial. We now look forward to further developing this candidate and bringing us one step closer to improving outcomes for people living with respiratory diseases.. ”
Cystic fibrosis is estimated to affect more than 100,000 people worldwide and is associated with reduced life expectancy. Failure of mucociliary clearance and mucus congestion within the lungs leads to a cycle of infection and inflammation, leading to continued decline in lung function.
