The novel formulation and delivery technique, with Acrux' testosterone lotion applied directly to the armpit using a 'unique' no-touch application system, was able to restore normal testosterone levels safely and effectively with no adverse side effects.
The lotion form created by Acrux makes use of the company's proprietary technology platform, whereby a drug, penetration enhancer and volatile solvent are combined to result in a quick-drying formulation absorbed rapidly by the skin.
Current testosterone replacement therapies focus largely on gels, patches and injections, which can be messy, inconvenient and can run the risk of cross-contamination.
According to Acrux, the company's under-arm lotion can tackle these issues whilst offering comparable therapeutic effect to the traditional hormone treatments.
"The product attributes for Testosterone MD-Lotion will deliver significant benefits for patients when compared to existing testosterone gel products," Hugh Alsop, director of business development at the company told in-PharmaTechnologist.com.
"The unique 'no-touch' method of application...will avoid the mess of sticky hands, and reduce the risk of cross-contamination of the product via touching.
The product is fast drying, has no lingering odour or tackiness, and has a total application time, including drying, less than the leading gel."
Another key selling point, according to Alsop, is the fact that the once-a-day armpit application is discreet and convenient, and can be considered part of a daily grooming routine.
The testosterone lotion itself will be supplied with a unique applicator which will be used in a similar way to an under-arm deodorant to apply the product to the skin.
The applicator consists of a flexible reservoir that holds the lotion, has no moving parts and according to Alsop is light, easy to hold and inexpensive to manufacture.
Patients dispense the lotion into the applicator by depressing a metered dose pump and then apply directly to the armpit.
The product dries within a few minutes, with the penetration enhancer allowing the treatment to pass through the skin, where it forms a depot and is slowly released into the bloodstream.
After use the applicator is rinsed with warm water and dried with a tissue ready for use the next day.
Each bottle of the product is supplied with an applicator, and is designed to be disposable once the bottle is finished.
The cost is anticipated to " compare very favourably " with other testosterone products currently on the market.
Acrux has currently developed two doses for the testosterone lotion, a starting dose of 30mg and a higher dose of 60mg.
At the lowest dose, a single bottle of the lotion will provide just over a month's worth of daily treatment.
"This compares very favourably to the leading gel which requires two bottles to supply one month's treatment," said Alsop.
"Additionally, the second top selling gel product requires 30 separate tubes per month at the starting dose."
The company is currently in the process of investigating the potential effects of deodorants and antiperspirants on the efficacy of its under-arm testosterone lotion, in order to determine the eventual labelling and usage instructions for the product.
The study will also look at the effect of washing the application site, and the potential for transfer from patient to other people.
The company has decided to complete the remaining development of the product in-house, with Phase III development (due to start in early 2008) anticipated to cost the firm approximately $20m (€14.5m).
Acrux has the facilities to manufacture clinical trial supplies at its site in Australia, but is also currently on the look out for a contract manufacturer to take over commercial manufacturing, with technology transfer hoped to take place early next year in time for regulatory submissions in 2009 and product launch in 2010.
With an international patent pending that covers the application of a number of drugs to the armpit which will provide against competing products through to 2026, and the testosterone lotion already covered by existing Acrux patents through to 2017, the company has high hopes for the innovative product.
According to the company, the male testosterone replacement market is estimated to be worth over $600m, and growing at a significant rate of 14 per cent each year.
With the apparent advantages the Acrux product seems to offer, combined with patent protection of the novel drug formulation and delivery method, Alsop's prediction that the product could capture "a significant share of the testosterone gel market" would appear well-founded.