While the discussion about precision medicine largely focuses on tailoring treatments to specific individuals to improve outcomes, another benefit is emerging: the ability to reduce waste that comes from ineffective treatments.
Scientists are bringing precision medicine to rheumatoid arthritis for the first time, in fact, by using genetic profiling of joint tissue to see which drugs will work for which patients, according to a new Northwestern Medicine study.
Even though the study is particular to rheumatoid arthritis, hospital executives deciding whether or not to invest in precision medicine programs should know that the same practices could be applicable to other conditions and treatments as well.
In the near future, patients won't have to waste time and be disappointed with months of ineffective therapy, scientists said -- and providers won't have to waste money and resources on treatments that are ineffective.
With a glut of biologic drugs, treatment for rheumatoid arthritis is basically trial and error, with no real rhyme or reason behind giving one drug as opposed to another. According to researchers, the healthcare industry wastes $2.5 billion per year on ineffective therapy. And patients get upset, because they often endure up to 12 weeks of therapy without seeing results.
Scientists in the multi-site study were the first in the U.S. to use ultrasound-guided therapy to take a tissue biopsy in the affected joint. In the past, blood samples were used to try to determine the effectiveness of the therapy and disease progression. Improved ultrasound guided techniques make the new approach possible.
Scientists in the six-site study analyzed the tissue in 41 rheumatoid arthritis patients, separating different immune cell populations. They focused on macrophages -- essentially the garbage collectors of the immune system, which are overactive in rheumatoid arthritis. These cells produce toxic, inflammatory proteins that destroy the joints. Biologic therapy removes the protein molecules being secreted by the macrophages.
In the past, scientists have tried to determine therapeutic effectiveness by separating patients into groups based on their clinical parameters, such as what antibodies they are producing against themselves, how swollen their joints are and the medications they're taking. Then scientists tried to see if these parameters could predict therapeutic efficacy. But that hasn't worked.
Instead, the researchers segregated patients based on the genes being produced by their macrophages. They identified two patient groups who shared aspects of the genetic profiles. Next, they identified which of these populations had joints that were getting better and which biologic therapies they were taking. They also identified a gene sequence associated in patients with early disease. The earlier the patient is treated, the more effective the therapy.
The next goal is to predict which patients will have the best response -- based on their genetic signature -- to a specific drug, thereby eliminating the trial-and-error element of treatment and curbing waste.