Parkinson’s and nerve growth factors

Progress in the field of neurotrophic factors

Infusion:

In the recent trials in Bristol of GDNF and in Scandinavia with CDNF, a novel convection enhanced delivery device developed by Renishaw has been used.  This has enabled pin-point precise delivery of the molecules to the brain and has ensured that the nerve growth factors are only delivered to the area where brain cells have been affected. The device has not received regulatory approval so can only be used in a clinical trial setting.  However Herantis Pharma has opted to explore alternative delivery approaches for CDNF that would not involve invasive brain surgery for infusions of growth factors.

Gene therapy:

There is an urgent need for treatments to slow or stop the progression of Parkinson’s and the use of gene therapy via gene replacement offers the potential to achieve this with a single treatment. The development of conventional treatments for Parkinson’s meeting their target in the brain is made particularly difficult due to the blood-brain-barrier (BBB) which protects the brain from harmful compounds circulating in the bloodstream; and viral vectors (or carriers) have shown potential in certain neurodegenerative gene therapy applications. Researchers are using carefully engineered viruses that act as biological delivery vessels to ‘infect’ brain cells with their engineered genetic contents – in this case the gene needed to make nerve growth factor. This pioneering delivery approach removes the need for invasive surgical infusion treatment.

Other novel delivery mechanisms into the brain

Work is intensifying in the delivery of small fragment nerve growth factors to the brain, such as the Cure Parkinson’s funded study of C-CDNF.  If effective in the laboratory, these small fragments may be developed for subcutaneous or nasal delivery which would be less invasive and therefore could make growth factors a viable restorative therapy for people with Parkinson’s.

Nanoformulation:

A recent paper from Dr Olesja Bondarenko and Professor Mart Saarma, published in Frontiers of Cellular Neuroscience, reviews the array of different nerve growth factor delivery methods for Parkinson’s based on the clinical trials of GDNF and CDNF to date, as well as the current and future possibilities of using nano-sized particles as carriers of these drugs into the brain.