Patrys (ASX:PAB), a therapeutic antibody development company, has announced further pre‐clinical data for its drug candidate PAT‐DX1, its humanised version of the 3E10 anti‐DNA antibody.
Drs James Hansen and Jiangbing Zhou of Yale University have shown PAT‐DX1 administered by tail vein injection crossed the blood brain barrier to significantly reduce tumour size in an orthotopic animal model of glioblastoma using human tumour explants.
According to the company, evaluation of brain sections showed the glioblastoma tumours in mice treated with PAT‐DX1 were more than 40 per cent smaller than the comparable tumours in control mice.
The blood brain barrier is a protective layer of endothelial cells that only allows certain molecules to transit from the blood into the cerebrospinal fluid that surrounds the brain. The blood brain barrier is a significant challenge to the delivery of therapeutics because only a very limited number of molecular classes can cross into the brain.
To date, very few proteins or antibodies have been shown to transit across the barrier from the blood to the brain.
Glioblastoma is a particularly aggressive, highly malignant form of brain cancer characterised by very fast cellular reproduction. Glioblastomas constitute approximately 15 per cent of all primary brain cancers and are a significant unmet therapeutic need, with a median survival period of 18 months, depending on disease severity.
“We are delighted with this significant discovery” said Dr James Campbell, CEO and managing director of Patrys.
“The blood brain barrier is one of the major limitations in the development of neuro‐therapeutics, and the observation that PAT‐DX1 can cross the barrier and reduce glioblastoma tumour size is very positive. With our collaborators at Yale we are currently undertaking a parallel study to evaluate the comparative survival of mice with glioblastoma that have been treated with PAT‐DX1 versus untreated mice, and will report on this in the coming month.”