A set of algorithms and graphs developed by UCLA researchers could help clinicians determine how much medicine a cancer patient needs to maximize tumor shrinkage.
Doctors, professors and graduate students at Ronald Reagan UCLA Medical Center began to devise an individualized method of treatment called phenotypic personalized medicine, or PPM, about 15 months ago that tailors drug dosages to specific patients.
The National Cancer Institute and the National Science Foundation, among other organizations, funded the research published Wednesday in Science Translational Medicine.
“We treat biological systems like a glass box,” said Dean Ho, a researcher and professor in the oral biology and medicine division at the UCLA School of Dentistry. “It works for cells, it works for animals and it works for people. No matter what it is, there’s an optimum that exists for that person.”
Ho said he worked with Ali Zarrinpar, an assistant professor of surgery in UCLA’s liver and pancreas transplantation division, to select eight liver transplant patients at the hospital for the study. Doctors typically give transplant patients one to two milligrams of a drug called tacrolimus, an immunosuppressant that helps prevent the patient’s body from rejecting its new organ.
Doctors are trained to administer a standard dose based on patients’ average response to the drug, but PPM allows doctors to adjust dosage based on factors such as other drugs the patient is taking and whether the patient develops complications, Zarrinpar said.
He added PPM technology yields a personalized graph for each patient, showing doctors how much tacrolimus they should administer to obtain the desired result.
PPM is also useful for recalibrating dosages as the patient progresses with treatment or builds resistance to certain drugs, Ho said.
“(Zarrinpar’s team) got us drug levels and we came back with the dose,” Ho said. “Communication was seamless.”
Zarrinpar said the team is especially interested in applying PPM to liver cancer and bacterial infections. Recently, researchers launched a study sponsored by the Food and Drug Administration, with UC Irvine and UC San Diego, to compare the effects of two types of tacrolimus using PPM.
The multidisciplinary research helped Zarrinpar and his medical colleagues approach clinical care from an engineering perspective, he said. He added he thinks doctors often focus on finding out the causes of the disease, so an engineering mindset helped the clinical team simplify the problem and yield practical solutions, he said.
“Ultimately, we’re treating individuals and caring more that the treatment works, as opposed to understanding why our treatments would not,” he said.