More than skin deep
If you suddenly have a headache in Europe or the USA, your most likely response is to take a couple of painkillers.
In Japan and elsewhere in Asia, however, the response of a sufferer is more inclined to reach for a cooling patch to be applied to the forehead.
“Transdermal products were invented in Japan, which is perhaps one reason why the local application of patches is still so popular in much of Asia,” says Yoshiki Matsuyama, global sales representative for medical products at Tokyo-headquartered nonwovens manufacturer Japan Vilene, which is now part of Freudenberg Performance Materials. “Westerners usually rely on tablets and sprays, while the Japanese prefer patches and powders.”
Transdermal medication, however, is on the rise worldwide – and for good reason.
For one thing, unlike traditional local pain therapies and medications with pills, transdermal drug delivery has no effect on the body’s digestive system. In addition, pharmaceutically-active ingredients can be accurately and safely dosed in a simple manner.
While thermal patches for treating back ailments are perhaps most commonly known, the range of medical patches is now much wider. Current products include, for example, pain patches, hormone replacement patches, nicotine patches and patches that help alleviate asthma, as well as patches that nurses use to administer drugs to sufferers of Alzheimer’s or Parkinson’s diseases. There are even special patches that allow the gentle administration of painkillers to cancer sufferers.
According to NanoPharma, the Czech Republic-based manufacturer of nanofibre nonwoven products, 31% of the $4.2 billion transdermal drug delivery patch market – predicted to grow to a value of €7.4 billion by 2025 – is currently based on delivery of the drug Fentanyl, used for treating a range of problems including pain management and chronic wounds.
Freudenberg, however, draws an important distinction between two types of transdermal patch – topical and passive.
Topical patches are only intended to act locally, at the exact spot on the body to which they are applied, for a duration of between 12 and 24 hours. Thermal patches of this type, for example, only warm the area where they are in direct contact with the skin. For large topical patches, it is very important that the patch lies well, adapting to skin movement and feeling pleasantly soft, which are qualities nonwovens can guarantee.
With passive patches, drugs and other active ingredients enter the bloodstream through the skin without ‘active’ support, such as electronic impulses. Typical applications for patches of this kind are the treatment of Alzheimer’s and Parkinson’s patients, but they are also commonly used to dispense nicotine and hormones into the body.
With passive patches, the great advantage is that they enable the long-term, controlled release of drugs through the skin.
“Tablets involve a so-called ‘first-pass effect’ – some of the orally-administered active ingredient does not even reach the bloodstream but remains lodged in the liver and intestines,” explains Leonardo Graziadio, sales manager for the medical sector at Freudenberg Performance Materials in Germany. “With a patch, controlled delivery over an extended period of up to four days is possible and in addition, patches do not interact with food intake, which can influence the effectiveness or concentration of the drug. A further advantage is that as soon as the patch is applied to the skin, there is no need to remember to take the medication later. This is especially valuable for children, who generally do not like swallowing tablets, or for forgetful patients. The limits of passive application, however, lie in the molecule size of the medication – if the molecules are too large, they cannot diffuse through the skin.”
Soft and flexible
For transdermal patch applications, Freudenberg Performance Materials offers very soft, flexible and conformable backing materials and release liners that protect the adhesive surface based on hydroentangled nonwovens. For non-injection, targeted medications such as nicotine patches and hormone patches, the company’s ultra-thin nonwoven-film composites have proved to be a further ideal solution.
Japan Vilene has been producing these nonwovens since 1991and supplying the European market since 2009. Now, Freudenberg Performance Materials and Japan Vilene consult and deliver them to customers globally.
As an all-female company intent on rapidly launching a range of new consumer products, beginning this year with a dry cosmetic face mask, Nanopharma is meanwhile currently making plans to launch a new transdermal patch product branded Nanopatch, specifically targeting the controlled delivery of Fentanyl.
“The key problems with current transdermal patches on the market are their poor efficiency, the possibility of abuse through high dosages, drug leakage and delayed release,” says CEO Liliana Berezkinová. “Nanopatch is a zero waste, pain-free and self-administrative system which makes very efficient use of the drug payload compared to conventional reservoir-based patches.”
With Nanopatch, she adds, the synergistic effects of the nanocomponents can replace the role of skin penetration enhancers to allow for an all-nanofibre nonwoven product.
“It provides controlled absorption and more uniform plasma drug concentration and allows extended drug release,” Berezkinová explains. “The benefits for pharmaceutical companies include the efficacy of active substances with low oral bio availability and controlled even application, with no peak concentrations. It is easy to manage the dosage by varying the area of the patch and there is no loss of the active substance.
“Potentially, the Nanopatch will require significantly lower amounts of the active ingredient than is required with tablets or solutions too. For patients, it offers safe, reliable and pain-free application and will make it easier to treat children, as well as older patients and those requiring complex care.”
BioPharma is now working on the integration of biodegradable nonwovens into the electrospinning and lamination processes and also on new methods of cold lamination.
“We are constantly looking for new application areas, as well as extending our strategic alliances,” Berezkinová concludes.
Expect to see many more new applications for advanced nonwovens in the medical sector at INDEX™20 in Geneva.
Images courtesy: Freudenberg and Nanopharma (both from companies).