After centuries of delivering drugs to patients as pills, liquids and injectables a revolution is under way which will change everything for patients – from the dose needed to the frequency of administration.
Life for patients will be transformed by drug delivery systems which will release a steady dose of many kinds of drugs over periods of days or weeks without relying on their memory.
By delivering the drug directly to the site where it is needed, the dose can also be reduced with no loss of efficacy.
Changing the way drugs are delivered turns on its head the oft-stated issue that there is a problem with the way patients comply with drug delivery regimens. Instead, the technology takes account of fallibility, patients who stop taking medication because they believe they no longer need it and plain bad memory, increasing the efficacy of existing medicines.
For example, Intarcia announced the development of a subcutaneous osmotic mini-pump called Medici which can deliver compounds steadily for up to one year.
Launching the technology, Kurt Graves, chairman, president and CEO of Intarcia, said: “One of the biggest problems in chronic diseases is millions of patients lack effective control of their condition due to sub-optimal effectiveness of their medication, and the fact is, the majority of patients with chronic conditions stop taking these pills and injections after just three-to-six months.
“We are aiming to address these serious and costly unmet needs by introducing a new way to deliver once-yearly therapies that hold the potential for game-changing improvements in outcomes and patient adherence over time.”
Once placed just beneath the skin, water from the extracellular fluid enters the pump device at one end – by diffusing through a semi-permeable membrane directly into a salt osmotic engine – that expands to drive a piston at a controlled rate. This forces the drug within the pump to be released in a steady, consistent fashion.
The company says that Medici has the potential to be used in chronic conditions such as diabetes, obesity, autoimmune and other serious diseases. It is currently researching new therapies.
Another area in which the new technology could have benefits is the battle against malaria.
In rural areas with poor infrastructure and less direct access to healthcare malaria is one of the major health problems facing the population. Drugs exist to treat the infection but one of the greatest problems is enabling patients to take them in the right way.
Researchers funded by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) at Massachusetts Institute of Technology (MIT) have come up with a novel solution to delivering the mosquito-killing drug Invermectin.
The new system is a capsule which, when swallowed, opens up flower-like into a star-shaped structure which will not pass further through the digestive tract, releases its drug load slowly over about two weeks before eventually disintegrating.
“This drug delivery system is the kind of low-cost solution that could have a great impact on the spread and destructiveness of malaria,” said David Rampulla, Ph.D., director of the NIBIB program in Delivery Systems and Devices for Drugs and Biologics.
In another, and very different, effort to reduce dosage and increase efficacy various companies have been developing microneedle systems, particularly for vaccinations. Using microneedles delivers the vaccine into the dermis, stimulating an immune response with a lower dose. Not only that, but it overcomes the objections of needle-phobic people, increasing take-up.
In May, two companies announced their intention to cooperate in developing the market for this new technology. They are Vetter from Germany and Microdermics from Canada.
Dr Claus Feussner, Vetter’s senior vice president development service, said: “We believe that microneedles are a particularly innovative technology and may prove to be a promising future alternative for selected areas of drug delivery.”
A simple way to deliver drugs to a specific site would be with an adhesive patch but there are many practical problems to be overcome to produce a patch which can contain enough of the drug while maintaining its adhesive capabilities.
Researchers at the University of Warwick have worked with Coventry-based Medherant, a Warwick spinout company, to produce and patent the world’s first ever ibuprofen patch delivering the drug directly through the skin to exactly where it is needed, at a consistent rate.
The University of Warwick researchers and Medherant have found a way to incorporate significant amounts of the drug into the polymer matrix that sticks the patch to the patient’s skin with the drug being delivered over up to 12 hours.
Now the problems have been overcome in the case of ibuprofen it opens the way for other drugs to be delivered in the same way for the treatment of chronic conditions such as chronic back pain, neuralgia and arthritis without the need to take potentially damaging doses of the drug orally.
University of Warwick research chemist Professor David Haddleton said: “Our technology now means that we can for the first time produce patches that contain effective doses of active ingredients such as ibuprofen for which no patches currently exist. Also, we can improve the drug loading and stickiness of patches containing other active ingredients to improve patient comfort and outcome.
“There are only a limited number of existing polymers that have the right characteristics to be used for this type of transdermal patches – that will stick to the skin and not leave residues when being easily removed. Furthermore, there are also only a limited number of drugs that will dissolve into these existing polymers. Medherant’s technology now opens up the field of transdermal drug delivery to previously non-compatible drugs. We believe that many other over the counter and prescription drugs can exploit our technology and we are seeking opportunities to test a much wider range of drugs and treatments within our patch.”
