Drugmaker Ionis Pharmaceuticals in Carlsbad reported positive early stage data on a potentially groundbreaking drug to reduce the underlying cause of Huntington’s Disease.

In a Phase 1/2 trial Ionis’ antisense drug RG6042 reduced the levels of a mutant protein found in patients with Huntington’s Disease.

Over 13 weeks, the two highest doses of RG6042 were linked to a 40 percent mean reduction in the mutant protein, with as much as a 60 percent decline. With the study finished, a further drop is anticipated.

Swiss pharmaceutical giant Roche paid Ionis $45 million to license the drug, it was announced in December. Next, Roche will run a pivotal trial of the drug candidate to gauge clinical efficacy and safety.

In the U.S. the neurodegenerative disease, marked by the deterioration of mental abilities and physical control, affects 30,000 people, and 200,000 are at risk of inheriting it.