Roche sees cause for optimism with failed Huntington's disease drug. Others aren't so sure.

This week, Roche released detailed results of a closely watched and, ultimately, unsuccessful study testing an experimental treatment for Huntington's disease that it's been developing alongside partner Ionis Pharmaceuticals.

The study, which enrolled hundreds of participants, was previously stopped early, on the recommendation of outside experts who concluded Roche's drug was not likely to be any better than a placebo at improving patients' brain and motor function.