A Study to Evaluate the Efficacy and Safety of Intrathecally Administered RO7234292 (RG6042) in Patients With Manifest Huntington's Disease

Open to people ages 25-65

• Manifest HD diagnosis, defined as a DCL score of 4
• Independence Scale (IS) score >= 70
• Genetically confirmed disease by direct DNA testing with a CAP score >400
• Clinical assessment to ensure individual has intact functional independence at baseline to maintain self-care and core activities of daily living (ADLs).

• Any serious medical condition or clinically significant laboratory, or vital sign abnormality or claustrophobia at screening that, in the investigator's judgment, precludes the patient's safe participation in and completion of the study
• Pregnant or breastfeeding, or intending to become pregnant during the study or within 5 months after the final dose of study drug