A Phase 1 Study of Inhaled KB408 for the Treatment of Alpha-1 Antitrypsin Deficiency
The Sponsor is developing KB408, a replication-defective, non-integrating herpes simplex virus type 1 (HSV-1)-derived vector engineered to deliver functional full-length human SERPINA1 to the airways of people with alpha-1 antitrypsin deficiency (AATD) via nebulization. This study is designed to evaluate safety and pharmacodynamics of KB408 in adults with AATD with a PI\*ZZ or PI\*ZNull genotype. Three planned dose levels of KB408 will be evaluated in single dose escalation cohorts. Repeat dosing will be evaluated at the mid dose level. Subjects taking intravenous AAT augmentation therapy are not required to wash out from IV AAT in the low and mid dose cohorts. In the repeat dose and the high dose cohorts, subjects must wash out from IV AAT for at least 10 days, as applicable.
• The subject or legally authorized representative must have read, understood, and signed an Institutional Review Board (IRB) approved Informed Consent Form and must be willing and able to comply with study procedures and instructions.
• Subject is aged ≥18 to ≤70 years, at the time of informed consent.
• Subject has a genetically confirmed diagnosis of AATD with a PI\*ZZ or PI\*ZNull genotype.
• Cohort 2b and Cohort 3: Subjects receiving AAT augmentation therapy must be willing to washout for at least 10 days prior to Screening and be willing to remain off augmentation therapy for the duration of the study.
• Cohort 2b and Cohort 3: Serum AAT level \<11 μM at Screening.
• Willing to remain on a stable regimen of treatment during the study.
• Resting oxygen saturation ≥92% on room air at Screening.
• Clinically stable and in good general health, except for AATD, as determined by the Investigator.