Alvelestat (MPH966) for the Treatment of ALpha-1 ANTitrypsin Deficiency

Inclusion criteria

• ✓. Capable of giving signed informed consent as described in Appendix 3, which includes compliance with the requirements and restrictions listed in the informed consent form and in this protocol
• ✓. Age ≥18 and ≤80 years
• ✓. Patients with a confirmed diagnosis of AATD: Pi\*ZZ, Pi\*SZ, Pi\*null, or another rare phenotype/genotype known to be associated with either low (serum AAT level \<11 μM or \<57.2 mg/dL) or functionally impaired AAT including "F" or "I" mutations.
• ✓. FEV1 ≥25% predicted
• ✓. Patients will be eligible if they are either a) are not currently receiving augmentation treatment and have not received augmentation in the 12 weeks prior to screening or b) have received weekly infusions of augmentation at 60 mg/kg for at least 12 weeks prior to screening and intend to continue augmentation through the study period.
• ✓. Male or female sex a. Male participants must agree to use a highly effective contraception as detailed in Appendix 5 during the treatment period and for at least 4 days after the last dose of study treatment and refrain from donating sperm during this period b. Female participants are eligible to participate if not pregnant; not breastfeeding; and at least one of the following conditions is met: i. Not a woman of childbearing potential as defined in Appendix 5 OR ii. A woman of childbearing potential who agrees to follow the contraceptive guidance in Appendix 5. During the treatment phase and for at least 4 days after the last dose of study medication.