Farmacokinetiek van monoklonale antilichamen

- Monoclonal antibodies (MOABs) are, due to their specificity, increasingly being deployed for therapeutic purposes. - MOABs are derived from immunoglobulins and are fully or partially of murine or human origin. They are administered parenterally: mostly intravenously, but subcutaneous or intramuscular administration is also possible, in which case absorption probably occurs through the lymphatic system. - The distribution of MOABs from the bloodstream into the tissues is slow and is hampered by the high molecular size of the MOABs, which is a lesser problem for fragments of antibodies (Fab fragments). - MOABs are metabolised to peptides and amino acids. This process takes place in many tissues of the body, but probably predominantly in epithelial cells. - As a consequence of the saturable binding of the MOAB to its target, a dose-dependent (non-linear) elimination is often observed. - Immune reactions can accelerate the elimination of antibodies, partially depending on the degree of humanisation of the antibody. - Antibodies and endogenous immunoglobulins are protected from elimination by binding to protective receptors (neonatal Fc-receptor; FcRn), which explains their long half-lives (up to 4 weeks). - Metabolic pharmacokinetic interactions with other drugs have not been reported and are not expected. - It is expected that in the years to come, new MOABs directed towards new targets will appear on the market, as well as existing antibodies with improved pharmacokinetic properties.