Researchers Exploring Personalized Drug Therapy
Friday, December 22, 2006
At San Diego's Galloway Pharmacy, the staff churns more than 100 prescriptions an hour.
Thanks to Internet orders and a brisk walk-up business, things are always jumping at Galloway. In fact, the store is so busy, Galloway uses a robot to package some of its fastest moving medications.
But whether it's Lipitor for high cholesterol, or amoxicillin for a sinus infection, most patients receive the same dose. It's basically one size fits all.
People may some day look back and consider this system to be extremely primitive. Galloway's owner Fadi Atiya says in the future, drug therapy will likely be completely different.
Fadi Atiya: We'll have a formula, and we put in there the patient weighs this much, and he or she is this tall, and once we plug in all these factors, and we get their genetic makeup, I believe that in the future we can specifically tailor medications for these patients.The idea of personalized drug therapy may sound farfetched. But the study of the human gene structure could eventually produce such a development.
Years ago, scientists began to examine why some people reacted differently to standard doses of medication. Researchers concluded these reactions were the result of genetic variables that ran in certain families.
Dr. Paul Insel is a professor of pharmacology at UCSD. He says today, it's believed all individuals metabolize drugs in subtly different ways.
Dr. Paul Insel: And so, we've become sensitive to the idea that we are all unique individuals in our drug response, much in the way that we all look different from one another. And so the challenge is to identify what those differences are, and how we can influence our ability to prescribe and take drug in individuals.That's where the science of genomics comes in. Researchers are just beginning to understand the role of genes in disease. The field of pharmacogenomics seeks to find out how a person's genetic makeup influences their response to drugs.
Insel: The concept of personalized medicine is really what we hope will evolve from the information that's being gleaned in this area. So that the drugs that you or I might receive for the same medical condition could be different and could be tailored to us, in a way that would maximize our chance of having benefit, and minimize our chance of having side effects and toxicity.The field is in its infancy. But some doctors are using genetic testing to help them in their practice.
Dr. Jennifer Willert is a pediatric oncologist at Rady Children's Hospital.
Dr. Jennifer Willert: The majority of our children with either disorders of the blood, hematology disorders, or cancers, most of them do have molecular testing associated with it, that either helps you make the diagnosis…It also helps guide us is what type of treatment is best for that patient.But Willert points out doctors are not yet able to customize chemotherapy for different tumors ... nor can they tailor-make treatment based on a patient's genetic profile.
Not surprisingly, the drug industry is vitally interested in pharmacogenomics. And so are many biotech companies.
La Jolla-based Sequenom designs equipment for genetic analysis. Dr. Charles Cantor is the firm's chief scientific officer.
He thinks the idea of personalized drug therapy is a double-edged sword for the pharmaceutical business.
Dr. Charles Cantor: If people have genetically predictable differential responses to medication, it's going to be hard to have a large blockbuster drug, because any given drug will be optimal for a subset of the therapeutic population, and not the whole population.Cantor says on the other hand, drug companies could benefit from more detailed genetic information.
Cantor: If you design your clinical trial with this in mind, you may be able to rationally include or exclude people through the various stages of clinical trials, and as a result of that, I think it's almost certain, that drugs will be brought to market sooner.Recently, Pfizer had to abandon a new cholesterol drug after spending 800-million dollars on it. With that in mind, the drug industry is searching for quicker and cheaper ways to develop new medications. Advances in pharmacogenomics could help in that effort. Kenny Goldberg, KPBS News.
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