18 February 2026
A recent study has found that treating patients with Idiopathic Pulmonary Fibrosis (IPF) with the drug nalbuphine ER reduces both measured and reported cough frequency.
Published in JAMA and led by Professor Philip Molyneaux, consultant respiratory physician, at Royal Brompton Hospital, the CORAL study was a double-blind, placebo-controlled clinical trial, which is a type of trial where neither the patients nor the researchers know who is receiving the real treatment or a placebo (dummy) treatment, ensuring the results are fair and unbiased, and it was conducted at 52 sites across 10 countries.
IPF is a respiratory condition where the cause is unknown. It is a chronic progressive lung disease in which scarring of lung tissue makes breathing increasingly difficult. Up to 80% of patients with IPF are impacted by coughing. Research has shown that more severe coughs are associated with worse patient outcomes, including decreased quality of life and survival. This research aimed to improve the quality of life of IPF patients by finding effective treatments for IPF-associated coughs.
A previous clinical trial, also carried out at Royal Brompton Hospital, showed that nalbuphine ER, which targets the receptors involved in the cough reflex arc, the body’s mechanism for clearing the airways, was effective in reducing cough rates in IPF patients. In that earlier study, all patients received both the drug and the placebo. However, in this follow up study, participants were placed into separate groups that each received only one treatment, with the groups running in parallel.
The CORAL study had 165 patients with IPF who were divided into four groups: three groups received increasing doses of the drug, and a fourth group received a placebo. All participants were given their assigned treatment twice daily over a period of 6 weeks. Cough frequency was measured in two ways: objectively using a digital cough monitor, and subjectively through patients’ own reports.
Participants in the study were adults who had been diagnosed with IPF and, when screened, also had a chronic cough for at least 8 weeks that scored above a 4 on the cough severity numerical rating scale and who met other criteria around vital capacity and blood oxygen saturation.
The results of this trial demonstrated that after 6 weeks, all three doses of nalbuphine ER reduced objective cough frequency compared with placebo. It also showed that the two higher doses improved patient-reported cough frequency at 6 weeks. The study concluded that future longer-term studies would be warranted.
When commenting on the study Professor Molyneaux stated:
“These findings are really encouraging for the majority of patients with IPF who suffer with cough. Not only can we reduce cough frequency, but these reductions are associated with tangible improvements in patients’ quality of life.”
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