Research by Drs. Rolf Kreutz and David Flockhart is changing the way medications are prescribed. Take a look in your medicine cabinet. How much do you know about the medications inside? In fact, how much does anyone really know about how the pills we ingest wend their way through our bodies and work their wonders? Not enough, it turns out. But a team of physicians and scientists at the Indiana University School of Medicine is taking a leading role in discovering more about how some commonly used drugs work and how an individual's genes affect the response. Full Article
Dr. Renbarger Studies Vincristine
Jamie Renbarger, M.D., has made two new discoveries with a drug that was approved in 1963, opening the door to new knowledge that may further help children with cancer. Renbarger knew that vincristine -- which is widely used to treat cancers in children – led to side effects that varied considerably between patients. But why? In the lab, she discovered that two enzymes, CYP3A5 and CYP3A4, metabolize vincristine differently. CYP3A5, which is found in approximately 70 percent of African-Americans and 10 percent to 20 percent of Caucasians, metabolizes vincristine much more efficiently than CYP3A4. Knowing which enzymes to target, Renbarger next compared toxicity in Caucasians with African Americans who had Acute Lymphoblastic Leukemia. She showed that Caucasians developed side effects – such as jaw pain, loss of reflexes, and constipation -- with vincristine more often than African-Americans possibly due to the fact that the CYP3A5 enzyme is found in fewer Caucasians. Currently, Renbarger is enrolling 140 children with preB acute lymphoblastic leukemia to determine the optimal dosing of vincristine for pediatric patients, which may improve survival for young cancer patients. Renbarger's studies tie into the Best Pharmaceuticals for Children Act (BPCA), which established a process for studying drugs used in children with the goal of improving pediatric therapeutics. Vincristine has been identified as a priority drug to study. Because of the ongoing studies at the IU Simon Cancer Center, Renbarger and her team are generating data unlike any other research currently underway.