Ionis Pharmaceuticals has reported positive topline results from the Phase IIb RE-THINC ESRD clinical trial of a new anti-thrombotic therapy, fesomersen, in end-stage renal disease (ESRD) patients on haemodialysis. 

The double-blind, randomised, placebo-controlled trial analysed the safety, pharmacokinetics and pharmacodynamics of multiple doses of fesomersen in 307 patients. 

Bayer, which had obtained a licence to fesomersen from Ionis, carried out the trial. 

In the trial, subjects were categorised to receive 40mg, 80mg or 120mg subcutaneous dose of fesomersen or placebo every four weeks for a duration of up to 48 weeks. 

Occurrence of major bleeding and clinically significant non-major bleeding was the trial’s primary endpoint. 

According to the trial findings, fesomersen met the primary outcome measure of no rise in major bleeding and clinically relevant non-major bleeding events versus placebo. 

Furthermore, all tested doses of fesomersen were found to be safe and well-tolerated. 

It also showed to provide a substantial and statistically significant decline in activity levels of Factor XI.

An investigational antisense therapy, fesomersen is claimed to reduce Factor XI production.

Factor XI is a clotting factor produced in the liver and is the coagulation pathway’s vital component. Its increased levels raise the blood clot formation risk inside blood vessels also called thrombosis.

Ionis Pharmaceuticals senior vice-president, chief medical officer and metabolic and liver franchise leader Sanjay Bhanot said: “For decades, anticoagulants have been a therapeutic mainstay in the treatment and prevention of thrombosis. 

“However, they can be associated with increased bleeding risk, which can lead to major, sometimes fatal, bleeding events. 

“The results of the RE-THINC ESRD study demonstrate fesomersen’s potential as a novel anti-thrombotic treatment for cardiovascular and renal disease patients.”

In November last year, the company initiated the Phase III CORE trial of olezarsen for severe hypertriglyceridemia.