Too often, we take for granted how easy it is to get and use medicine that treats a variety of ailments, both minor and major. Get a headache, develop arthritis, catch a cold or suffer an allergy attack, and you can swallow a pill and feel better. Topical medicines can take care of itching, rashes and pain. Meanwhile, a strategically placed shot can ease joint pain, and vaccinations can help ensure we don’t get sick at all with a particular illness.
It’s actually pretty amazing that we can introduce a foreign substance into our bodies in a variety of ways — oral, topical, injection — and create a desired effect. Drug delivery methods, however, can have drawbacks, too. Some medicines may not move easily throughout the circulatory system or through tissues and cells. Others may lose efficacy as they pass through the digestive system. Or medicines may cause harmful side effects to healthy organs and tissues.
New solutions: Drug delivery systems
Drug delivery systems combine one or more traditional drug delivery methods with engineered technology. These systems create the ability to specifically target where a drug is released in the body and/or the rate at which it gets released. This ability benefits patients in multiple ways.
A targeted drug delivery system can allow doctors to transport medicine to an exact location in the body — a cancerous tumor, for example — while minimizing or even eliminating systemic side effects and/or damage to tissues surrounding the treatment site. Targeted delivery can also help ensure the medicine reaches the area where it’s needed without any degradation that might occur if it has to pass through bodily systems like the digestive tract or circulatory system.
This delivery method can also help bypass the body’s natural defenses that may block foreign substances — even needed medicine — from entering individual cells. The medication reaches the diseased or damaged location quickly and at maximum efficacy.
Controlled release drug delivery systems are a natural evolution of the concept that’s made timed-release oral medications successful. These systems time the release of medication that may be administered in multiple ways, such as orally, by injection or implantation. This can allow physicians to maintain a specific level of medication within the patient’s body, reduce the need for repeated administrations of a medicine, optimize the efficacy of a drug, and even bypass the pitfalls of patients failing to take medicine as prescribed.
The role of bioabsorbable polymers
For many new drug delivery systems, bioabsorbable polymers make the magic possible. Bioabsorbable polymers like hydrogels, polylactic and polyglycolic acid and their copolymers, polyurethanes and others can be used to create the delivery component of the system. Whether the drug delivery system relies on a biodegradable implant to deliver medicine subcutaneously or deep within the body, biodegradable polymers provide a safe framework for delivering medicine without harm. And because they ultimately degrade and absorb in the human body, bioabsorbable polymers eliminate the need to remove the drug delivery system once the medication has been released.
Researchers continue to develop new drug delivery systems to better meet either or both objectives — targeting or timing — for a variety of medications to treat a wide range of diseases. They’re even beginning to explore the idea of drug delivery systems that will be able to diagnose and treat diseases in a single step — and that will be truly amazing!