A medication used to treat alcoholism works in only a fraction of patients who take it. Several years ago, researchers at the University of Pennsylvania School of Medicine found the reason why — a difference between patients’ genes. Now, Doctor David Oslin at Penn and his colleagues are looking to put that genetic information to work — in helping doctors write prescriptions. WHYY’s health and science reporter Kerry Grens spoke with Oslin about the medication, naltrexone.
To hear more about tailoring medicines to our genes, attend a special event at whyy wednesday (6/20) evening. You can find more information and RSVP here.
Oslin: “It works by reducing people’s cravings for alcohol. So it reduces their urges or desires to want to drink. So therefore it’s a good treatment option for people who are trying or struggling with addiction.”
Grens: “What was some of the evidence that it wasn’t working for all patients?”
Oslin: “Many of the studies that have been done in this area have shown that the effect of naltrexone, while is robust, it’s not robust in all patients. And actually a lot of our patients would come back and tell us that it was working very well for them in a very strong way or some of them would come back and say I know I’m on the placebo pill and it’s not working. Based on reports from our patients we actually started to explore, are their predictors or ways to actually understand why the medicine might work for some people better than other people.”
Grens: “What tipped you off that it might be genetic?”
Oslin: “The first hint we got was looking back at family history and hearing from patients participating in these studies that family history may be an important player and we published some work a number of years ago on family history effects. And based on family history you would obviously go after issues around genetics.”
Grens: “Can you tell me what you found, what gene was involved?”
Oslin: “So the medication naltrexone works at a receptor in the brain, again to reduce people’s craving for alcohol, and it turns out that about a quarter to a third of people have a different type of that gene or a different variation of the gene that changes how that gene translates into the protein and functions. So it works differently. In this quarter to a third of patients that have the genetic change they actually respond more robustly to the medication.”
Grens: “Can patients request to be tested if they’re concerned that their treatment isn’t working?”
Oslin: “Right now, as best as I know, there’s no commercial test available for the genotyping. So we’re still in the domain that this is kind of a research only availability.”
Grens: “Have your findings impacted the way doctors are prescribing treatments for patients?”
Oslin: “It’s a little early in the story yet to change clinical practice but we’re very much on the verge of this. We’ve had several conversations with the FDA about how to take this and translate it into both labeling changes for the drug as well as dissemination in the clinical practice. This fall we’ll actually be starting one of the first prospective pharmaco studies in this area where we’re going to be recruiting patients with alcohol depedence and randomly assigning them to treatment based on their genotype. And that will be first in the field.”