NRx Pharmaceuticals has reported that the Data Safety and Monitoring Board (DSMB) of the ACTIV-3b (TESICO) clinical trial recommended halting analysis of Zyesami (aviptadil) in critical Covid-19 patients due to futility.

The DSMB reviewed the findings of nearly 460 critical Covid-19 patients with respiratory failure enrolled in the trial, most of which had attained the 90-day endpoint. 

The trial is sponsored by the US National Institutes of Health unit National Institute of Allergy and Infectious Diseases (NIAID).

In a press statement, NRx Pharmaceuticals said: “The DSMB recommended stopping further randomisation to aviptadil due to aviptadil not meeting the futility guidelines outlined by the pre-approved analytical plan.” 

The primary endpoint of the 90-day six-category ordinal score and the 90-day mortality secondary endpoint were found to be unsupportive.

In the trial, a mortality rate of 37% was reported in the aviptadil arm versus 36% in the placebo arm.  

No safety concerns were observed in the trial while the known side effects of aviptadil, specifically diarrhoea and hypotension, were well managed with the protocols in place.

Zyesami was the only remaining investigational therapy being analysed in the ACTIV-3b trial in critical Covid-19 patients.

The ACTIV-3b Critical Care Study analysed Zyesami and Veklury (remdesivir) in critical Covid-19 patients, as a single agent and in combination versus placebo.

NRx Pharmaceuticals Interim CEO Robert Besthof said: “We thank the NIH and the Trial Leadership for its extensive work in studying Zyesami (aviptadil). 

“We will continue to work closely with them to better understand the data over the coming months. 

“This will also enable us to evaluate the options for Zyesami in protecting the lung in other respiratory disorders, as well as its potential in other therapeutic areas.”

In February this year, the company reported that the NIH trial of Zyesami for the treatment of critical Covid-19 will advance to complete full subject enrolment.