Safety, Tolerability and Pharmacodynamic Effect of Fazirsiran (TAK-999, ARO-AAT)

Inclusion Criteria:

   - Diagnosis of AATD

   - Liver biopsy at Screening indicating liver fibrosis (score less than F4); a patient
   with no fibrosis may participate based on a previous biopsy conducted within one year

   - Women of childbearing potential must have a negative pregnancy test, cannot be
   breastfeeding, and must be willing to use contraception

   - Willing to provide written informed consent and to comply with study requirements

   - Non-smoker for at least 1 year

   - No abnormal finding of clinical relevance at Screening

Exclusion Criteria:

   - Clinically significant health concerns other than AATD

   - Previous diagnosis or diagnosis at Screening of definitive liver cirrhosis

   - Previous lung or liver transplant due to AATD

   - Regular use of alcohol within one month prior to Screening

   - Use of an investigational agent or device within 30 days prior to dosing or current
   participation in an investigational study involving therapeutic intervention

   - Use of illicit drugs within 1 year prior to Screening

NOTE: additional inclusion/exclusion criteria may apply, per protocol