Oral delivery of biologics including therapeutic peptides and proteins as well as DNA/RNA-based drugs is certainly a great challenge. In order to reach the systemic circulation after oral dosing these hydrophilic macromolecular drugs have to overcome various barriers being encountered with the GI-tract. In particular the enzymatic barrier (I) being represented by secreted and membrane bound enzymes cleaving them in inactive fragments, the sulfhydryl barrier (II) causing unintended thiol/disulphide exchange reactions between thiols being present in the GI-tract and peptide/protein drugs, the mucus gel barrier (III) restricting macromolecules from reaching the absorption membrane and the absorption membrane barrier per se (IV) are responsible for a comparatively very low oral bioavailability. In order to overcome these barriers, various technologies were explored. Among them, self-nano- and micro-emulsifying drug delivery systems (SNEDDS and SMEDDS), collectively named as self-emulsifying drug delivery systems (SEDDS) have received considerable attention within recent years. Due to the complexation with lipophilic excipients biologics can be incorporated in the lipophilic phase of SEDDS. Once emulsified in the GI-tract to lipid droplets in the size of 30-200 nm, SEDDS provide a protective effect towards a presystemic metabolism, efficiently permeate the intestinal mucus gel layer in order to reach the absorption membrane and provide permeation enhancing properties. Moreover, as SEDDS can be produced in a very simple and cost effective manner, they might have the potential of game-changing delivery systems for the oral administration of biologics.
Take Home Message:
SEDDS are not carrier systems in that you can simply incorporate your drug gaining a sufficiently high oral bioavailability. The potential of SEDDS lies in the huge flexibility for the design of appropriate formulations fully addressing the peculiar properties of each biologic. Within this development process formulation IP is generated.
A short interview with you
Tell us a little-known fact about yourself! In parallel to my academic career I run a pharmacy standing behind the counter and selling drugs.
What do you foresee as being the biggest game changers in your industry over the next 5-10 years? So-called ‘drug delivery platform technologies’ are not anymore the future. In particular for the delivery of biologics the game will change to drug delivery companies providing individual solutions for each of these drugs based on a high expertise in the particular field.
What advice would you give a younger you? If certain strategies/concepts do not prove to be a success within an expected time period, to be much earlier open for alternatives.
What are your three biggest challenges on a day-to-day basis? 3x Doing research in parallel to all these teaching and administrate responsibilities
What has been the proudest moment of your career to date? Realizing that first drugs being based on a technology (thiomer-technology) I have invented and developed over the years are reaching the global pharmaceutical market.