Researchers from Monash University, collaborating with Seaport Therapeutics, have unveiled a promising new way to deliver medicines orally by harnessing the body’s natural fat-absorption pathways.
The approach could open the door for treatments that once required lengthy intravenous infusions to instead be taken as a simple daily pill.
The work, published in Science Translational Medicine, centres on a modified form of allopregnanolone, a neurosteroid already known for its antidepressant, anti-anxiety and sleep-supporting effects. Until now, its clinical use has been limited because it must be administered through a prolonged IV infusion, making it impractical for routine treatment.
The research team developed a strategy to chemically link the drug to a lipid, allowing it to masquerade as dietary fat during digestion. This shift changes the route the compound takes through the body. Instead of passing through the liver, where many drugs are broken down before they can act, the modified molecule is absorbed via the lymphatic system and delivered directly into the bloodstream.
The liver typically acts as a gatekeeper, filtering substances absorbed from the gut and often dismantling fragile drug molecules before they reach their target. By sidestepping this first-pass metabolism, the new formulation allows therapeutically meaningful levels of the drug to circulate in the body.
The engineered compound, known as GlyphAllo, also incorporates a carefully designed chemical linker that keeps the drug stable in the digestive system but releases it once it enters the bloodstream. This balance ensures that the medicine survives the journey through the gut while remaining active at the right time.
Early clinical trials have provided encouraging results. In Phase 1 studies involving healthy volunteers, oral doses of GlyphAllo were generally well tolerated and produced allopregnanolone levels in the bloodstream consistent with therapeutic effects. Follow-up Phase 2a testing used a well-established stress model and showed that a single dose significantly reduced cortisol levels compared to placebo, indicating a measurable dampening of the body’s stress response.
These findings suggest the approach could be particularly valuable in treating major depressive disorder, where allopregnanolone’s effects are already well documented but difficult to access due to delivery constraints. A larger Phase 2b trial is now underway to evaluate the drug’s effectiveness in people living with depression, with or without accompanying anxiety.
Beyond this specific therapy, the implications of the technology may be even broader. By enabling drugs to hitch a ride on the body’s fat transport system, the platform could help revive a range of promising compounds that have previously failed due to poor absorption or rapid breakdown in the liver. Researchers believe the same strategy could eventually be applied across fields as diverse as oncology, immunology and metabolic disease.