A Study to Evaluate ALN-HTT02 in Adult Patients With Huntington's Disease

Inclusion Criteria - Has stage 2 or early Stage 3 Huntington's disease (HD), per the Huntington's Disease Integrated Staging System (HD-ISS) Exclusion Criteria - Has significant structural or degenerative neurologic disease other than Huntington's Disease (HD) at screening - Has primary or secondary immune compromise at screening due to infections, medical conditions, or chronic therapies - Has alanine aminotransferase or aspartate aminotransferase \>2× upper limit of normal (ULN) - Has an estimated glomerular filtration rate (eGFR) of \<60 mL/min/1.73m\^2 at screening - Has received an investigational agent within the last 1 year or 5 half-lives (if known) Note: other protocol defined inclusion / exclusion criteria apply Always talk to your doctor about whether this trial is right for you.