New Micro Drug Delivery System Reduces Side Effects, Costs

Pharmaceutical Drug Delivery System – Colon/Lung Diseases

An improved directed pharmaceutical drug delivery system for the treatment of patients suffering from colon and lung diseases, inclusive of lung cancer which is the leading cause of cancer death in Australia, is being developed by Professor Neil Foster from the WA School of Mines, Energy and Chemical Engineering.

Professor Neil Foster had spent 20 years researching, developing and commercialising innovative pharmaceutical drug delivery systems at Curtin as well as at his earlier role as a chemical engineering professor at The University of New South Wales – UNSW. He had initiated two companies while at UNSW, namely Eiffel Technologies, currently known as Telesso Technologies and Bio Particle Technologies, to commercialise his research.

Foster has been an internationally recognized expert in the arena of supercritical fluids and dense gas technology. Towards mid-1990s Foster together with his colleague, Dr Angela Dillow from the University of Minnesota had approached MIT Professor Robert Langer who was one of the leading biomedical engineers of the world in developing a chemical agent from the supercritical fluid carbon dioxide which could be a cleaning as well as a sterilising agent.

Thereafter the technology had been licenced to a specialist development company known as NovaSterilis which had further enhanced the technology for sterilising transplanted human tissue, sensitive medical devices together with the other biomedical materials. Till date, Foster together with Langer tends to continue working in partnership with him.

Atomised Rapid Injection for solvent Extraction

The concept known as ARISE – Atomised Rapid Injection for Solvent Extraction, a technology re-engineers active pharmaceutical ingredients into particles not bigger than a few micrometres which means that they can be easily absorbed in the bloodstream of the body than the conventional pharmaceutical drug.

The ARISE process is a bottom up concept to drug micronization wherein the organic solution comprising of dissolved pharmaceutical ingredients are transported as an individual bolus injection strengthened under pressure variance in a vessel of static dense or supercritical carbon dioxide to influence solute drying. The quick injection method tends to eliminate the conventional usage of low flow-rates together with capillary nozzles or micro-orifices in accomplishing solution atomization.

Foster together with his research team had tested the efficacy on medications of the delivery system inclusive of the insulin; fluorouracil which tends to treat cancer, tobramycin that treats bacterial infections and fosfomycin, an antibiotic. Foster had explained that one of the issues experienced by the pharmaceutical industry was the shortage of new drug coming through the pipeline. In addition to the cost involved together with the relatively short patent life, it had driven pharmaceutical companies down the path of developing new delivery system and repurposing existing drugs.

Exploits Properties of Supercritical Fluids

If the research was successful, patients suffering from colon and lung diseases like irritable bowel disease, colorectal cancer, tuberculosis, cystic fibrosis and lung cancer would benefit from being prescribed lower dosages which would decrease the burden of drug on their bodies, related side effects together with the cost of the treatment.

Moreover, it would also reduce the cost of developing as well as gain market approval for fresh prescription medicine, estimated to be at US$ 2.6 billion as per the 2014 study by US non-profit research group Tufts Centre for the Study of Drug Development. Foster had stated that the prevailing treatment regiments for these disease state tends to be inefficient, frequently complex as well as time consuming and are associated with significant adverse side effect which contributes to poor patient compliance.

ARISE tends to exploit the properties of supercritical fluids together with gas expansion liquid technology. A supercritical fluid related to a substance wherein its pressure as well as its temperature are said to be above critical value providing it with the properties of gas and liquid. The gas-like properties have the potential to penetrate in a product and the liquid-like properties tend to dissolve the material in it enabling easy extraction.

Spontaneous Crystallisation of Pharmaceutical

Foster has summarised that by utilising decaffeinated coffee for instance, the supercritical fluid has the tendency of penetrating in the bean due to its gas-like properties, while its liquid-like properties permit the supercritical fluid to dissolve the caffeine.

 Then once again the gas-like caffeine takes over leaving the coffee bean and taking the caffeine with it. Though most pharmaceuticals do not tend to dissolve in supercritical fluids like supercritical fluid carbon dioxide, there seems to be an additional step involved wherein the pharmaceuticals tends to dissolve in a solvent like ethanol before the supercritical fluid is added to the mix.

Foster has explained that as the carbon dioxide is added, the solution tends to expand physically and as the solution expands, the density and the dissolving powers is said to decrease. At a specific degree of expansion, the solution does not have adequate dissolving properties to hold onto the pharmaceutical. What is observed then is spontaneous crystallisation of the pharmaceutical from the expanded solution – a gas expanded solution.

The following contributions of Foster has been extensively recognized –

•  He had been awarded a high-status Qian Ren – 1000 Talents, Professorship in 2010 by the People’s Republic of China that tends to encourage talented researchers from across the world in leading innovative research in China. He had been the only Australia-based, non-national Chinese scholar to be recognized at that point of time. 
•  He had been elected a member of the European Academy of Science and Arts in 2014, an independent transnational network which resolves intricate issues and Foster had been the only person out of three Australians to be given admission

Right through the duration of his career, Foster had trained, supervised as well as mentored around 39 higher degree research students together with 24 postdoctoral researchers and his main belief was that the research need not be for the benefit of research but also for commercial purpose with the potential of generating results which would benefit mankind.

The pharmaceutical tends to have very small particle size which is typically five micrometres or even less reduced to 50 nanometres which could be good in increasing the solubility of the drug in the bloodstream of the body. Moreover, the distribution of the size of the particle tends to be quite narrow which could be better to predict the onset of the therapeutic effect.