eFFECTOR Therapeutics has dosed the first subject in the second cohort of its Phase Ib clinical trial of zotatifin to treat adult Covid-19 patients in a non-hospital setting. 

The randomised, double-blind, placebo-controlled trial will assess the antiviral activity and safety of one zotatifin dose.

Under a Defense Advanced Research Projects Agency-sponsored cooperative agreement, worth $5m, the trial is being carried out in partnership with the Quantitative Biosciences Institute (QBI) at the University of California, San Francisco, US. 

The latest development follows a positive recommendation from the independent data safety monitoring board. 

The committee recommended dose escalation to the second cohort on assessing safety findings from the first cohort of subjects who received subcutaneous (SC) doses of zotatifin.

Initial data from the first cohort showed that SC doses had plasma drug levels in line with intravenous (IV) dosing.

An investigational, host-directed therapy, zotatifin is a sequence-selective, small molecule eIF4A inhibitor. 

It can hinder various cancer-driving proteins’ expression, including Cyclins D and E, and CDKs 2, 4, and 6, among others.

eFFECTOR Therapeutics president and CEO Steve Worland said: “Administered as a single dose injection, zotatifin aligns with the Test to Treat initiative being promoted by the US government and has the potential to overcome many of the limitations of existing treatment options, including poor treatment adherence that can result in viral rebound. 

“Achieving equivalent drug levels when zotatifin was delivered by the subcutaneous route provides an opportunity for convenient dosing in both the Covid and cancer settings.”

In June this year, the company reported positive data from its Phase I/II trial of zotatifin in solid tumour patients.