US-based pharmaceutical company Trevi Therapeutics has reported positive results from the Phase II Cough And NALbuphine (CANAL) trial of Haduvio (oral nalbuphine ER).

Conducted in the UK, the trial has been examining Haduvio’s efficacy for difficult-to-treat patients with chronic cough in idiopathic pulmonary fibrosis (IPF).

It was designed to evaluate the safety and efficacy of nalbuphine ER in adults with IPF chronic cough.

The trial found that treatment with nalbuphine ER led to a quick and marked reduction in recorded daytime cough among patients with IPF-related cough.

The study included two treatment periods of three weeks and had two weeks of washout period after each treatment period.

Its primary efficacy endpoint was to evaluate the nalbuphine ER tablets’ effect on the mean daytime cough frequency by an objective cough monitor at day 22 against placebo.

Safety results from the trial were also consistent with Haduvio’s safety profile as demonstrated in previous trials.

Treatment-emergent adverse events in the study included vomiting, constipation, somnolence, dizziness, nausea and fatigue.

Two serious adverse events were reported during the trial, but these were not related to the treatment.

Haduvio is a dual ĸ-opioid receptor agonist and µ-opioid receptor antagonist that exhibits synergistic anti-tussive effect and targets both the central and peripheral mechanisms of chronic cough.

Chronic cough may worsen fibrosis in IPF, leading to a higher risk of progression, need for lung transplant or death.

An estimated 140,000 IPF patients in the US and more than one million ex-US patients currently experience chronic cough.

Based in Connecticut, Trevi Therapeutics is preparing to begin the next clinical trial of Haduvio for the treatment of chronic cough in patients with IPF.

The company is also focusing its future clinical development on chronic cough conditions, including interstitial lung diseases, as well as refractory chronic cough.