Phosphagenics Limited recently announced positive results from a Phase Ib clinical study using the company’s patented TPM (Targeted Penetration Matrix) for the transdermal delivery of oxycodone. This successful trial showed that daily application of a TPM-oxycodone patch delivered therapeutic bloodstream levels of oxycodone in a reproducible, consistent, and sustained manner.

“The ability to reach therapeutic oxycodone plasma concentrations from a transdermal patch is a major achievement, and the sustained blood levels of this drug appear very suitable for chronic pain management,” said Professor Guy Ludbrook, Principal Investigator for the study and Head of Discipline, Anaesthesia & Intensive Care, at the Royal Adelaide Hospital. “After a dose of oral oxycodone pain relief is provided for only a matter of hours. The use of Phosphagenics’ oxycodone patch may provide sustained drug delivery for a matter of days, thus removing some of the peaks and troughs of pain relief associated with oral treatment.”

The open label, single centre pharmacokinetic study in 20 healthy volunteers was conducted at the Royal Adelaide Hospital. The primary objective of the study was to compare the delivery profiles of two transdermal patch candidates containing TPM, a matrix, and reservoir system, following daily application over a 10-day period. Plasma oxycodone concentrations were monitored throughout the study to assess which of the two patch systems produced the best delivery profile. Results from the study demonstrate that oxycodone plasma concentration increased throughout the entire 10-day dosing period after daily application of the matrix patch. Average plasma concentrations reached therapeutic levels and continued to rise daily during the 10-day study. Rapid drug elimination was also evident immediately after the removal of the final matrix patch on the tenth study day. The matrix patch had an oxycodone delivery profile that was much superior to the reservoir patch. Due to the evident superiority of the matrix patch over the reservoir system, as well as its greater potential to reduce drug abuse, Phosphagenics will continue development of only the matrix patch.

“The oxycodone Phase Ib trial was a very critical study and a key milestone for Phosphagenics, going beyond a proof-of-concept and demonstrating that our patch system can reproducibly deliver therapeutic amounts of oxycodone into the bloodstream. The therapeutic blood levels, the rapid elimination when the patch was removed, and the lack of skin irritation observed during the study, together with the likelihood that the patch will reduce drug abuse, makes our TPM-oxycodone patch extremely attractive commercially,” said Dr Esra Ogru, Phosphagenics’ Chief Operating Officer. “The continued increase in oxycodone concentrations over the duration of the experiment surpassed even our own expectations and further validates the power of TPM for transdermal delivery. We believe that this product will be ideal for management of chronic pain.”

As a consequence of this breakthrough clinical trial, Phosphagenics is planning the next stage of its oxycodone development. Under the guidance of Professor Guy Ludbrook, Phosphagenics has assembled an advisory panel of international pain experts to plan the path forward into Phase II/III trials and beyond. It expects to commence its next clinical study in the second half of this year.

Phosphagenics’ TPM delivery system is capable of topically delivering small molecules, such as opioids, and large molecules, such as insulin, into the blood circulation in a non- invasive manner. Phosphagenics has pioneered the development of TPM to significantly improve the therapeutic value of many drugs. The oxycodone matrix patch is the fifth product candidate based on Phosphagenics’ TPM technology to enter clinical development, and the first transdermal system to successfully deliver therapeutic oxycodone plasma concentrations for the management of pain without causing sensitization or irritation. Several cosmeceutical products utilising TPM are currently being commercialized through corporate partners. Other products based on Phosphagenics’ TPM technology in clinical development include products for the treatment of diabetes, pain, dermatology, and other diseases.

Phosphagenics is a Melbourne-based, globally driven biotechnology company focused on the discovery of new and cost-effective ways to enhance the bioavailability, activity, safety, and delivery of proven pharmaceutical and nutraceutical products. Phosphagenics’ core technology is built around the science and application of phosphorylation, a process where the addition of a phosphate group has been found to enhance the bioavailability, activity, and safety of existing pharmaceuticals and nutraceuticals, as well as to assist in the production of drug delivery platforms.