A recent study, the PACIFY COUGH trial, has investigated the use of low dose controlled-release morphine as a potential treatment for cough in individuals with idiopathic pulmonary fibrosis (IPF). IPF is a progressive lung disease characterized by fibrosis, and cough is a common symptom reported by patients with this condition. The trial, conducted in three specialist centres in the UK, aimed to assess the efficacy of morphine compared to a placebo in reducing cough frequency in IPF patients.

The PACIFY COUGH study, a phase 2, multicentre, randomised, double-blind, placebo-controlled, two-way crossover trial, enrolled eligible patients aged 40–90 years with a diagnosis of IPF within 5 years, self-reported cough lasting more than 8 weeks, and a cough visual analogue scale (VAS) score of 30 mm or higher. The participants were randomly assigned to receive either placebo twice daily or controlled-release morphine 5 mg orally twice daily for 14 days, followed by a crossover after a 7-day washout period. Both patients and medical personnel involved in the study were unaware of the treatment allocation.

The primary endpoint of the trial was the percentage change in objective awake cough frequency from baseline, as assessed by digital cough monitoring at day 14 of treatment in the intention-to-treat population. The safety data were also summarized for all patients who took at least one study drug and did not withdraw consent.

Results from the trial showed that morphine reduced objective awake cough frequency by 39·4% in the intention-to-treat analysis. The study enrolled 44 participants, with a mean age of 71 years, and the majority of the participants were male. Lung function measurements indicated moderately impaired function in the enrolled patients.

The findings of the PACIFY COUGH trial suggest that low dose controlled-release morphine may have potential as an antitussive therapy for individuals with idiopathic pulmonary fibrosis. However, further research and larger studies are warranted to confirm these results and to evaluate the long-term efficacy and safety of morphine in managing cough in IPF patients.