Ionis Pharmaceuticals Inc. and its affiliate Akcea Therapeutics Inc. said inotersen delivered better outcomes than placebo in a phase 3 genetic disease study.
The trial, called Neuro-TTR, enrolled 172 patients with polyneuropathy due to hereditary transthyretin-related amyloidosis, a potentially fatal disease characterized by abnormal protein deposits that commonly form in the heart and nervous system.
The study, which evaluated inotersen against a placebo, met its main goal of significantly improving neurological dysfunction and quality of life. Inotersen reduced abnormal protein deposits by more than half in nearly 90% of the patients.
Patients with cardiac issues due to hATTR amyloidosis also had protein deposits in their hearts shrink after receiving inotersen. Meanwhile, cardiac measures for patients in the placebo group increased on average.
No new safety concerns were observed in the trial. The results were presented at the 16th International Symposium on Amyloidosis in Kumamoto, Japan.
Additionally, Ionis and Akcea are conducting 12-month, open-label extension studies to see inotersen's long-term benefits. So far, patients who initially received a placebo in Neuro-TTR saw decreased disease progression, while patients exclusively treated with inotersen continue to have greater benefit.
An investigator-sponsored phase 2 trial also supported findings in the Neuro-TTR study, the companies said in a news release.
Inotersen is under priority review in the U.S. and accelerated assessment in the EU, whose regulators both granted the drug orphan status. Ionis recently sold the rights to the drug to Akcea in a deal valued at up to $1.7 billion.