Augmentation therapy, also known as replacement therapy, is a treatment for patients with severe alpha-1 antitrypsin (AAT) deficiency who have emphysema. It uses alpha-1 antitrypsin protein derived from the blood of healthy donors to increase the amount of AAT in the lungs of patients with AAT deficiency. In healthy individuals, AAT protects the lungs from being damaged by the body’s immune system. For AAT deficient patients, increasing the amount of AAT in the lungs using augmentation therapy helps to protect the lungs from further damage. AAT therapy is not a cure for AAT deficiency and does not reverse lung damage that has already occurred, but it can slow the deterioration of lung function over time.
The AAT protein is administered intravenously, usually once per week for the duration of the patient’s life. Augmentation therapy is most often administered directly into the bloodstream using an intravenous catheter (a soft plastic tube that is inserted into a vein using a needle, usually in the forearm). In some patients, the veins become damaged by repeated insertion of needles and catheters. When this happens, doctors may decide to use a central venous catheter that is connected to a "port" placed under the skin. The port is easily accessible to administer the infusion; it remains in place as long as the patient receives the augmentation therapy. This prevents the need for repeated needle sticks.