Getting Drugs to Where They Are Needed Most

Only about 5 percent of any drug actually makes its way to where it’s needed to treat a headache or slow and reverse disease. That’s because the harsh environment of the digestive tract destroys much of the medication, or the compounds have difficulty getting across cell membranes to reach their intended targets. 

As a result, people must take much larger doses than they require. Many drugs, in fact, cannot survive the journey at all. That’s why insulin must be injected rather than taken orally to treat diabetes, and treatments for macular degeneration and glaucoma commit patients to monthly injections or cumbersome eye drops taken multiple times a day. 

Tejal Desai, PhD ’98, who chairs UCSF’s Department of Bioengineering and Therapeutic Sciences, and her collaborators are on the cusp of solving these problems and revolutionizing drug delivery. Using micro- and nano-fabrication techniques developed by the computer chip industry, Desai’s team is creating tiny devices that deliver multiple drugs directly to where they are needed, using less medication, minimizing side effects, and making the process safer for patients. 

These microscopic devices stick directly to the intestinal wall, for example, and can be programmed to deliver the right amount of drug that can be quickly absorbed into the bloodstream to reach the intended destination. Others can be injected once and gradually release needed drugs over several months before being replaced. Treatments for eye disease may soon be delivered via a micro-thin film – much like a contact lens – that is capable of delivering a steady flow of medication for as long as six months. 

In classic UCSF style, this work brings together scientists, clinicians, and engineers with wide-ranging expertise – from building nanotechnologies and computing to medicine, pharmaceutical sciences, and genetics. That marriage will ultimately lead to better care for patients.