Verona Pharma has enrolled and dosed the first patient in a clinical study assessing its investigational drug RPL554 as a treatment for cystic fibrosis (CF).

The primary goal of the double-blind, placebo-controlled, Phase IIa single-dose trial is to evaluate the pharmacokinetic and pharmacodynamics profile and tolerability of RPL554 in up to 10 CF patients, as well as examine the effect on lung function.

RPL554 is a first-in-class, inhaled, dual inhibitor of the enzymes phosphodiesterase 3 and 4 (PDE3/PDE4) with anti-inflammatory as well as bronchodilatory properties, currently being developed by the firm for the treatment of chronic obstructive pulmonary disease (COPD) and CF.

In preclinical trials, the drug was found to stimulate the CF transmembrane conductance regulator, a protein whose mutation results in dysfunctional ion channels in epithelial cells, leading to CF. According to Verona, the available data indicates that RPL554 has the potential to help reduce phlegm in the airways, reduce airway obstruction and inhibit inflammation.

Previous clinical trials of the drug in patients with COPD have shown that RPL554 can induce statistically significant improvements in lung function as compared to placebo as well as other clinically meaningful and statistically significant improvements in lung function when added to two commonly used bronchodilators as compared to either bronchodilator administered as a single agent.

The trial in patients with CF, which is being performed at the Cambridge Centre for Medical Research at Papworth Hospital, Cambridge, UK, is being funded by a Venture and Innovation Award from the UK Cystic Fibrosis Trust issued to Verona in October last year.

Jan-Anders Karlsson, Verona’s chief executive, noted that two recently approved therapies for the condition are indicated only for a subset of CF patients, "and there is a need for novel, effective anti-inflammatory medications to treat the underlying inflammation in cystic fibrosis".

“RPL554 has a differentiated mechanism of action and preclinical data in cystic fibrosis combined with our positive clinical data in COPD leads us to believe it has the potential to be an important new treatment for this debilitating condition. We look forward to progressing the drug through this study and expect to announce top-line data in the first half of 2018.”

“The RPL554 trial has the potential to make a difference to the lives of people with CF, and we are thrilled that the drug is moving into this important trial stage,” added Paula Sommer, head of Research of the UK Cystic Fibrosis Trust.