Taking drugs made for you

Pharmacogenomics isn’t a word that trips easily off the tongue.

It derives from “pharmacology” and “genomics,” which is the study of chromosomes — all of an organism’s inheritable traits. Medical specialists have coined the term to cover an emerging field in biotechnology that is the study of how an individual’s genetic makeup affects his or her response to drugs.

While futuristic in sound, and even somewhat in conception, pharmacogenomics contains elements that, in the future, could change the way medicine is practiced, say scientists and educators versed in its practice and potential.

It conceivably has the capacity to deliver very specialized drugs based on a person’s genetic profile, according to Alan McKay, dean of the School of Pharmacy at Shenandoah University in Winchester, Va.

Pharmacogenomics is a subset of a broader concept known as personalized medicine, an umbrella term for a range of therapies based on individual need. The development of drugs such as Gleevac, used in certain cases to help alleviate the symptoms of leukemia by interacting with the molecular structure of the disease-causing gene, is part of a movement known as targeted therapy.

Therapy can help alleviate the disease in a patient. Equally important is the need for preventive measures — diagnostic tests that show who is at risk for a disease — as well as predictive tests that can tell how an individual patient will react to prescribed medicines and avoid problems associated with the one-size-fits-all approach currently in general use.

The above are the result of the successful completion of the Human Genome Project, which mapped all human genes and set the stage for some remarkable advancements in the biotechnology field. The human genome is made up of an estimated 25,000 to 30,000 individual genes, of which 99.9 percent are identical from one person to another. The remaining one-tenth of 1 percent is what makes each person unique.

“But [it] also creates the variation that leads to genetic diseases, different responses to drugs and challenges for health professionals,” Mr. McKay says.

The introduction of a new undergraduate program being offered jointly this fall by Shenandoah and George Washington University underscores his statement that “pharmacogenomics will change everything about the delivery of health care.”

The academic major is believed to be the first of its kind in the country to be given at the undergraduate level and is intended to capitalize on the strength of Shenandoah’s pharmacy program, combined with GW’s emphasis on the basic sciences.

“Eighty percent of drugs [in research and development] are coming out of biotechnology. Everything we teach will be outdated in 10 years,” Mr. McKay says. “We have to train [students] how to use genetic drugs. … Office-based genetic testing will permit physicians to make more decisions on presently available drugs based on genetic profiles. And further down the track, they will address specific profiles.”

Already the Food and Drug Administration has approved a diagnostic tool from Roche Laboratories Inc. called the AmpliChip CYP450, which Mr. McKay calls an example of what will become standard practice in the future — possibly within 10 years. AmpliChip CYP450, a genetics-based test, can identify how a person will metabolize some commonly prescribed drugs. The logical next step is finding ways to use the test results to recommend proper dosages.

“We are still at the very early stages of understanding the field,” notes Jean Johnson, senior associate dean for health sciences in GW’s School of Medicine and Health Sciences. “I would be surprised if this is not a major that is becoming highly desirable, because it is where science is at these days. Having a plain biology major is just not enough. I would imagine three-quarters of students [in the degree program] will move into the doctor of pharmacy [program at Shenandoah], but some might want to go on in medicine or research. It is a quantum leap in how health care will be managed.”

In February, Dr. Francis Collins, director of the National Human Genome Research Institute (NHGRI) at the National Institutes of Health, spoke of a forthcoming “revolution in health care” in an appearance before the Personalized Medicine Coalition (www.personalizedmedicinecoalition.org), a newly formed group of health and medical professionals involved in the broadest possible study and application of molecular analysis. He compared present efforts to the state of the computer industry in the 1970s, saying “most of what’s going to happen in personalized medicine lies ahead of us, not behind us.”

While the Human Genome Project focused on what is commonly found in a human being’s genetic makeup, the future lies in understanding how the one-tenth of 1 percent variation affects health and disease, says Dr. Alan Guttmacher, NHGRI’s deputy director. Two ongoing projects at NIH are being done in this area in conjunction with research institutions worldwide.

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