Methods of Radiolabelling
A variety of techniques are available to label drug products with scintigraphic radiolabels including 99Tc, 111In, 153Sm, or 171Er.
Blended Manufacture
Quotient will manufacture the drug product on site, incorporating either 99Tc and/or 111In during the manufacturing process to deliver a homogenous blend of radiolabel throughout the dosage form. This is our favoured approach to radiolabeling.
If the manufacturing method is not readily transferable to Quotient, the Sponsor can incorporate “cold” samarium and/or erbium into the drug product, which can subsequently be activated to “hot” (by neutron activation) prior to being used in a clinical study
“Drill and Fill” or “inject and reseal”
This approach is typically used when manufacture of a drug product is not possible, for example when investigating a Competitor drug product. A minute hole is drilled into the drug product and filled with a radiolabel and then sealed. A similar approach is used for liquid filled capsules; the radiolabel is introduced via injection through the outer shell.
Surrogate Markers
For multi-particulate formulations, which are not designed to modify their own GI transit,(e.g. gastroretentive), a surrogate population of radiolabelled particles is introduced. The surrogate particles match the dimensions of the drug loaded particles and the two populations mix and transit through the GI tract together.