Theravance Biopharma has reported top-line data from Phase II clinical trial, where nezulcitinib (TD-0903) failed to meet the primary endpoint in hospitalised Covid-19 patients with acute lung injury and impaired oxygenation.
Nezulcitinib is an experimental, inhaled drug candidate designed as a lung-selective, pan-Janus kinase (JAK) inhibitor.
The therapeutic is being developed to potentially treat the cytokine release syndrome that is known to cause acute lung injury, ventilator use and high morbidity and mortality in Covid-19 patients.
In the initial dose-finding part of this Phase II trial, nezulcitinib was generally well-tolerated.
Data also revealed numerical improvements in clinical outcome, duration of hospital stay and fewer deaths versus placebo.
The decision to advance the 3mg dose of nezulcitinib into the larger Phase II trial is based on these dose-finding results.
However, in the larger Phase II trial, the drug candidate did not show a statistically significant difference in the number of respiratory failure-free days (RFDs) from randomisation through day 28 in the intent-to-treat (ITT) population.
RFDs were the double-blind, placebo-controlled, multi-centre trial’s primary endpoint.
Compared to placebo, the drug candidate also failed to meet the secondary goal with no difference in change from baseline at day 7 in SaO2/FiO2 ratio.
Furthermore, the trial assessed the proportion of patients in each category of the 8-point Clinical Status scale and the proportion of patients alive and respiratory failure-free at day 28.
Nezulcitinib showed a favourable trend in improvement for 28-day all-cause mortality and time to recovery, versus, placebo, the company said.
A post-hoc analysis in patients with CRP <150 mg/L demonstrated an improvement in 28-day all-cause mortality and time to recovery when treated with nezulcitinib compared to placebo.
Meanwhile, patients with CRP >150 mg/L in treatment and placebo groups had no difference in time to recovery or 28-day all-cause mortality.
Safety analysis found nezulcitinib to be well-tolerated.
Theravance Biopharma CEO Rick Winningham said: “Even though this Phase II study, enrolling more than 200 patients, did not meet the primary endpoint, we are encouraged by the trend in the pre-specified analysis of the 28-day mortality rate in the intent-to-treat population.”
The company will submit these data to various regulatory authorities for guidance on protocols to further assess nezulcitinib in acute hyperinflammation in the lung.
Theravance started dosing participants in Phase II Covid-19 study of TD-0903 in June last year.