What does the drug do?

ION363 (also known as Jacifusen) is an investigational antisense medicine that is designed to reduce the production of the Fused in Sarcoma (FUS) protein which can lead to rapid, progressive loss of motor neurons in some patients. Patients with a mutation in the FUS gene develop a rare form of ALS, referred to as FUS-ALS.

Phase 3

The Phase 3 trial to evaluate the safety and efficiency of ION363 is split into two parts. The first part of the trial will consist of patients randomised to receive a multi-dose regime of ION363 or placebo for 61 weeks. The second part is an open-label period where all patients in the trial will receive ION363 for 85 weeks. The primary outcome of the trial is change from day 1 to day 225 in rate of decline measured by the ALS functional rating scale (ALSFRS-R). You can read more about the trial here.

How can I take part in the trial?

Recruiting Sites

The trial is recruiting in the UK at the following sites:

Please contact the individual trial site, by clicking each site above, for more information on how to take part in the trial. 

Latest News


May 2022 - The protocol of the trial was changed to increase the length of the double-blind phase (from 29 weeks to 61 weeks). This is to increase the likelihood of detecting a clinically meaningful signal.


Dec 2021 - King's College London was the first trial centre in Europe to recruit participants for ION363

Last updated: 21/12/2022