Precision medicine is a relatively new branch of oncology that focuses on treating patients with an individualized, molecularly-matched therapy targeting one mutation in their tumor. While it has certainly proved to be effective in some cases, researchers at the University of California San Diego School of Medicine actually believe that combination therapies can be more successful. A recent report published in Nature Medicine revealed the result of their study that showed improved outcomes in patients whose cancer was resistant to therapy.
According to Jason K. Sicklick, MD, “response rates to therapies that target one alteration can be low and not durable.” Sicklick is an associate professor of surgery at UC San Diego School of Medicine and surgical oncologist at Moores Cancer Center. He’s also first author and co-principal investigator of the new study. The team’s approach was to create a personalized combination therapy for each patient rather than just one single alteration target.
The trial involved patients who were previously treated of metastatic cancer at either Moores Cancer Center or Avera Cancer Institute in Sioux Falls, South Dakota. The team used molecular data, which includes genomic profiling developed by Foundation Medicine, and presented the data to a tumor board of oncologists, pharmacologists, cancer biologists, geneticists, surgeons, radiologists, pathologists, and bioinformatics experts. This specialized board then worked together to come up with personalized, combination therapies that would target most of the genomic alterations in each patient’s tumors. A patient was considered to be “highly matched” ” if over half of their tumor mutations matched to a drug.
The study included 149 participants who had metastatic, treatment-refractory disease. 73 of these patients were matched to a therapy, 66 weren’t able to be treated because of disease progression, which shows how advanced their disease was.
The treatments given to each of the 83 patients were determined by the treating oncologist and the patient’s individual preference. 10 patients in total had entirely unmatched treatments. The drugs chosen included gene product-targeted drugs, hormone therapies, immunotherapies, and chemotherapies.
Patients who were treated with the combination approach showed an increase response rate to treatment and an improved overall and progression-free survival in those who were “highly matched” to a treatment. 50% of patients who were highly matched with combination therapies targeting multiple alterations experienced a response. This is compared to 22% who were either unmatched or less well matched.
“Having 50 percent of patients with heavily pretreated disease responding when highly matched speaks to the importance of personalized, precision medicine combination approaches,” said senior author and co-principal investigator Razelle Kurzrock, MD, director of the Center for Personalized Cancer Therapy at Moores Cancer Center.
The next course of action for the team is to figure out if they can improve the benefit of the treatment by implementing it earlier on in the course of disease.