Perth-based biotechnology company Phylogica (ASX: PYC) has announced a successful round of in vivo results in the evaluation of its cell-penetrating peptide (CPP) vaccine program.
Peptides are potentially valuable as the basis for future world-leading drugs and Phylogica has been developing ways of delivering those drugs intracellularly to address targets that would otherwise be deemed “undruggable”.
In the most recent experiments, mice were treated with various CPPs which were joined to a common antigen from the herpes simplex virus and were capable of triggering the creation of cytotoxic CD8+ T-cells when delivered into the cytoplasm of dendritic cells.
CD8+ T-cells are important for immune defence against intracellular pathogens, including viruses and bacteria, and for tumour surveillance, while dendritic cells are responsible for the initiation of adaptive immune responses.
After administration of the various CPP-antigen vaccines and allowing time for the generation of an immune response, spleens were taken from the mice to measure the levels of CD8+ T-cells created by their immune systems which were specific to the antigen introduced by the CPP.
Phylogica reported that its CPPs produced the greatest expansion in CD8+ T-cells across all groups of treated mice and proved that CPPs can trigger an antigen-specific immune response similar in magnitude to that raised against a herpes simplex infection.
In a complementary experiment, the T-cells generated in response to the vaccination had the ability to kill target cells which express the receptor that they are created to recognise.
The company said both experiments demonstrate the efficacy of the CPP-antigen conjugate in stimulating a CD8+ T-cell immune response that is capable of recognising and killing the target cell.
On the basis of the latest findings, Phylogica said it will expand its peptide vaccine program beyond oncology to include viral illnesses that can be treated with the same vaccination strategy.
A new generation of disease fighters
Phylogica originated from a collaboration between WA’s Telethon Institute for Child Health Research and the Fox Chase Cancer Centre in Philadelphia.
The company controls access to “the world’s most structurally-diverse” source of patented Phylomer peptides which have the ability to fight disease, acting as effective drug delivery agents and cargoes within the human body.
Phylomer peptides are believed to display exceptional structural stability, specificity and affinity, and have the potential to address disease targets that are intractable to small molecules and other protein biologics, including antibodies.
Phylogica is focused on commercialising its intracellular drug delivery platform and screening its peptide libraries to identify cargoes for development against a wide range of disease targets.
At midday, shares in Phylogica were up 9.68% to $0.034.