The trial, which compared the drug with a placebo, showed a statistically significant 12.4% reduction in a disease-causing mutant huntingtin protein, the company said in a statement.

When it comes to safety, the drug was “generally safe and well tolerated among patients receiving doses up to 16 mg in both single and multidose portions of the study,” Wave Life Sciences said.

Data from another Phase 1b/2a study, Precision-HD1, evaluating WVE-120101 in early manifest Huntington patients should be available in the second half of next year, Wave Life Sciences said.

The data do support “exploration of higher doses of WVE-120102, with the goal of maximizing mutant HTT reduction and avoiding a negative impact on the healthy huntingtin protein," said Michael Panzara, a physician and chief medical officer of Wave Life Sciences.

Huntington disease , often appearing in adults in their 30s and 40s, “is a progressive brain disorder that causes uncontrolled movements, emotional problems, and loss of thinking ability,” the National Institutes of Health says.

The drop follows a 55% decline Dec. 16, after Wave Life Sciences said it would abandon development of two Duchenne muscular dystrophy treatments.