Protein Drug Conjugates
Several of the Navigo-created, ready-to-go Affilin® molecules against solid tumor targets are currently developed as protein-drug conjugates (PDCs), by combining them to a half-life extending module and an engineered toxin-carrying moiety.
Compared to notoriously difficult-to-produce and inhomogeneous Antibody-Drug Conjugates (ADCs), Affilin®-based PDCs have clear advantages. They are easily assembled from a specificity-conferring Affilin®, a half-life extending module and a toxin-carrying moiety. Each of those modules can separately be optimized for its particular task and together they can be flexibly assembled into final drug candidates.
Affilin®-based PDCs can be single chain molecules, with engineered targeted carrier domains for specific drug conjugation sites and thus have a distinct Affilin®-drug ratio for minimal adverse effects. ADC manufacturability issues are greatly simplified by single chain Affilin®-drug conjugate expression in E. coli.
In a modular approach, the specificity conferring Affilin® targeting unit is coupled to a carrier unit with engineered sites for site-specific coupling of a cytotoxic payload. A half-life extending module can optionally also be added (not shown). By separating the carrier unit from the targeting unit, either one can be optimized and adjusted independently. Due to site-specific coupling, Affilin®-drug conjugates ensure homogenous end-products with defined drug-Affilin® ratios.