Determining the half-life of prophylaxis treatment using population pharmacokinetics
Hemophilia is a rare blood coagulation disorder caused by a deficiency or deformity in one of 12 primary clotting factors. Hemophiliacs experience insufficient healing and prolonged bleeding either from trauma or unprompted bleeding. We are able to maintain a level of the deficient factors in a patient through direct and immediate infusion of a drug into the blood. To determine the frequency of injections and the appropriate dosage, we need to consider how long a drug will stay in a child’s body. Tailoring prescriptions for each patient often requires the withdrawal of 11 blood samples over a period of only 24 to 72 hours – a taxing assessment for both clinicians and patients, particularly for children. Our objectives of this study are to predict the half-life of drugs for children with hemophilia (using only 2 or 3 blood samples) and to evaluate the variability in dose requirements among children to determine a target minimum safe level of the drug concentration in one’s body.