Clinical-stage biopharmaceutical company Trevi Therapeutics Inc (Nasdaq: TRVI) announced on Tuesday additional analyses from a Phase 2a RIVER trial of its Haduvio treatment for refractory chronic cough.

The company is developing the investigational therapy Haduvio (oral nalbuphine ER) for the treatment of chronic cough in patients with idiopathic pulmonary fibrosis (IPF) and in patients with refractory chronic cough (RCC).

In March, Trevi Therapeutics reported positive topline results in which Haduvio met the primary endpoint with a statistically significant reduction in the objective 24-hour cough frequency of 67% from baseline and 57% on a placebo-adjusted basis.

Further results show that responder analyses of 24-hour cough frequency reduction at 30%, 50% and 75% thresholds were statistically significant for patients on Haduvio across all doses. Additionally, there was a statistically significant improvement in the patient-reported Leicester Cough Questionnaire at Day 21 (108 mg BID).

There were no significant treatment period effects from the crossover design for the primary efficacy analysis of relative change from baseline in 24-hour cough frequency.

Similar to previous studies, adverse events for patients on Haduvio were more frequently observed following initial exposure to the drug at 27 mg BID in the first week and diminished over time despite dose escalation to 108 mg BID.