Precision Medicine is hot topic at ASCO
CHICAGO: A precision medicine approach using a patient’s individual tumor biomarkers to determine the best treatment leads to significantly better outcomes, according to data being presented at this year’s American Society of Clinical Oncology (ASCO) meeting.
A meta-analysis of 346 Phase I clinical trials involving more than 13,000 patients found that patients whose treatment was selected based on the molecular characteristics of their tumor benefited more.
The study was carried out by researchers at the University of California San Diego School of Medicine. Lead study author, Maria Schwaederle, from the university’s personalized cancer therapy unit, said:
“Our study suggests that, with a precision medicine approach, we can use a patient’s individual tumor biomarkers to determine whether they are likely to benefit from a particular therapy, even when the therapy is at the earliest stage of clinical development.
The study examined efficacy and safety data from 346 Phase I trials published between 2011 and 2013. The analysis included 58 treatment arms that employed precision medicine and 293 that did not. The researchers found that in treatment arms employing precision medicine, tumor shrinkage rates were 30.6%, compared to 4.9% in those that did not.
ASCO spokesperson Don Dizon said: “Precision medicine is not the future of cancer, it is the present. This study reinforces that the more we personalize treatment to the patient and the tumor, the better the outcomes – even in the earliest phases of research.”
Precision medicine is one of the hot topics at this year’s ASCO conference. The premise behind the approach is that doctors take a sample of the tumor to test for specific genetic changes that drive the tumor growth. They then select a treatment that precisely targets and destroys that particular mutation.
Currently, doctors largely rely on tumor biopsies, which involve a surgical procedure, but patients are not always healthy enough to undergo the procedure.
In a further study presented at ASCO researchers found that patterns of genetic changes detected in blood samples closely mirrored those identified in traditional tumor. The procedure is known as liquid biopsy. Small pieces of genetic material in the bloodstream (ctDNA) are analyzed to help inform treatment decisions.
In what is believed to be the largest ctDNA analysis, scientists at UC Davis Comprehensive Cancer Center in California revealed that liquid biopsy gave an unparalleled opportunity to monitor changes in cancer as it evolves over time.
The study included 15,191 patients with advanced lung cancer (37%), breast cancer (14%), colorectal cancer (10%) and other cancers (39%). Each patient provided one or more blood samples for analysis of ctDNA.
The results revealed that when ctDNA was positive for key abnormalities in EGFR, BRAF, KRAS, ALK, RET and ROS1 that drive tumor growth, the same mutations were reported in tissue 94-100% of the time.
Early results from MyPathway, a Phase IIa umbrella basket study being conducted at the Sarah Cannon Research Institute in Tennessee, were also presented at ASCO.
Researchers reported that 29 of 129 patients with 12 different types of advanced cancers responded to drugs outside of FDA-approved indications.
The most promising efficacy was seen among patients with HER2 abnormalities, according to the researchers.
Senior investigator John Hainsworth said:
“Although it is still early to draw conclusions, our findings suggest that, for example, HER2-targeted therapy could be expanded beyond the current indications of HER2-positive breast and gastric cancers. Our study gives strong early signals for activity of HER2-targeted therapy in HER2-amplified colorectal cancers and possibly other HER2-positive cancers.”
There are currently targeted treatments for more than 25 cancers, with many clinical trials underway to apply precision medicine to other cancers.
Earlier this week the US Food and Drug Administration (FDA) approved the first liquid biopsy test that can detect EGFR gene mutations in non-small cell lung cancer (NSCLC) patients, which are present in approximately 10-20% of NSCLC patients.
Swiss pharmaceutical and biotech firm Roche (ROG: SIX) becomes the first company to be granted US Food and Drug Administration (FDA) for a liquid biopsy test that can detect EGFR gene mutations in non-small cell lung cancer (NSCLC) patients.
Roche subsidiary Genentech and Japan’s Astellas Pharma are partnered to develop and distribute Tarceva in the USA, with Chugai (majority-owned by Roche) marketing it Japan and Roche in the rest of the world.
Albert Gutierrez, director of the office of In Vitro Diagnostics and Radiological Health at the FDA’s Center for Devices and Radiological Health, said: “Approvals of liquid biopsy tests make it possible to deliver highly individualized healthcare for patients. These tests also have the potential to allow physicians to identify patients whose tumors have specific mutations in the least invasive way possible.”
The Pharma Letter spoke to Dr Stephen Eck, chairman of the Personalized Medicine Coalition and interim head of oncology at Astellas Pharma, about the emergence and evolution of precision medicine.