TransPharma pushes transdermal parathyroid hormone
clinical trials of human Parathyroid Hormone 1-34 fragment (hPTH
1-34), delivered with its hand-held pen-size transdermal device,
showed its system can systemically deliver effective therapeutic
dosages, providing a painless, very low-cost, easy to use
application.
With this transdermally-delivered drug, TransPharma is eyeing the lucrative osteoporosis market, since over the next five years the osteoporosis population is expected to reach 52m, with an anticipated market potential of $10.4bn (€8.58bn) by 2011.
The hPTH (1-34) molecule is the only drug capable of bone building and is currently being administered by injection only, grossing sales of $3bn in 2010.
Although TransPharma will continue the development of hPTH (1-34) to late stage clinical trials, aiming to partner with a major pharma company to commercialise the product, it also intends to carry on developing products in collaboration with other companies similar to the agreement it signed with Teva Pharmaceuticals in 2004.
The drug delivery system used is based on a reusable pen-size device which creates microscopic passageways through the outer layer of the skin allowing for therapeutic administration of a wide variety of drugs from a 1 one square centimetre small patch, whether the molecules are big or small.
TransPharma has formulated of hPTH (1-34) into a stable printed dry-form patch that can deliver the molecule into a patient's systemic circulation with a peak blood profile.
Analysis of ionised calcium and phosphorus confirmed that the bioactivity of the delivered hormone was fully maintained.
"The efficacy of delivery is comparable to subcutaneous administration in terms of efficacy," Judith Kornfeld, TransPharma's vice president of business development, told In-PharmaTechnologist.com.
"The drug can be self-administered and is easy to operate by the patient without any risk of harming himself."
Passive transdermal drug delivery has been in use for over 20 years but has been successful only with a limited number of active molecules because very few drugs can passively diffuse across the skin barrier at therapeutically useful rates.
TransPharma's RF-MicroChannel Technology uses cell ablation technology to create micro-channels in the skin's surface, enabling transdermal delivery of drugs that cannot be delivered using coventional methods.
After a densely spaced array of microelectrodes is placed against the skin, a high frequency alternating current is transferred through each of the microelectrodes to create localized ablation of the skin cells in close proximity to the electrodes.
This painless process takes milliseconds and produces well-defined and completely safe RF-MicroChannels which penetrate only the outer layer of the skin, where there are no blood vessels or nerve endings.
What is more, the size and density of RF-MicroChannels enable delivery of relatively high doses of drugs, which could not previously be delivered transdermally.
As soon as the RF MicroChannels have been created, and the printed patch is applied, extra-cellular fluid, released by the body through the microchannels, comes in contact with the powder and dissolves it to form a saturated solution or suspension with an extremely sharp concentration gradient, resulting in efficient delivery.
The RF-MicroChannels formed in the skin remain open for a relatively long time, up to and exceeding 24 hours, allowing sustained-release drug delivery to maintain constant drug blood levels and improved compliance.
