Ionis Pharma’s ION582 shows positive Phase 1/2 results in Angelman syndrome

Ionis Pharmaceuticals announced positive results from the completed multiple ascending dose portion of the Phase 1/2 open-label study of ION582 in people with Angelman syndrome – AS – demonstrating consistent clinical improvement on measures assessing all functional domains including communication, cognition and motor function. Overall, 97% of people in the medium and high dose groups saw an improvement in overall AS symptoms. ION582 showed favorable safety and tolerability at all dose levels in the study. AS is a rare neurodevelopmental disorder that is caused by a loss of function in the maternal UBE3A gene. It affects an estimated 1 in 21,000 people worldwide. HALOS included 51 people with AS. These results include: ION582 showed favorable safety and tolerability at all dose levels. Evidence of consistent benefit observed across all ages and genotypes as well as clinical improvement observed across key functional areas. Clinical improvements were observed across key functional areas in parent-reported assessment tools. 97% of participants showed clinically meaningful overall improvement on the SAS-CGI-C, which evaluates clinicians’ impressions of AS symptoms in study participants. Ionis plans to meet with regulators to review and confirm their Phase 3 study design later this year, which puts the company on track for a pivotal study initiation in H1 2025.