Startup betting on ‘liquid biopsy’ to match cancer patients with trials

“We have no doubt these liquid biopsies will be one of the main, fundamental tools by which cancer is detected and treated.” HELMY ELTOUKHY

While many clinical trials fail because of bad results, nearly 1 in 5 fail because of low patient enrollment. In many cases, patients and their doctors don’t know they could be eligible to participate in a trial, which prevents promising treatments from reaching them.

Guardant Health, a 4-year-old company based in Redwood City, Calif., developed a liquid biopsy blood test that has helped match cancer patients with clinical trials and treatment options without costly or invasive biopsies. Instead, its Guardant360 test detects cancer DNA in a patient’s blood. CEO and co-founder Helmy Eltoukhy calls it’s a “game changer” for oncology.

“Many of these pharmaceutical companies would like to use a simple blood test rather than a biopsy as a companion diagnostic for their drugs,” Eltoukhy said. “It means many more patients will have access to the latest and greatest therapies.”

Studies have estimated as few as 3% of adult cancer patients are referred to clinical trials. Eltoukhy says that’s at least partially because only top medical centers generally have a pathologist on-site to perform biopsies. The Guardant360 blood test could be used to determine if stage 3 or 4 cancer patients have developed rare abnormalities that make them prime candidates for clinical trials.

Guardant believes blood tests will become a widely used alternative to traditional tissue biopsies and allow clinicians to more nimbly identify, monitor and treat cancerous tumors.

That promise has attracted $200 million in venture funding and the attention of many oncologists. Guardant has been marketing the technology since 2014 as a test developed in a CMS-certified laboratory and has started pursuing Food and Drug Administration approval through its pre-submission program. More than 20,000 patients have already been tested with it.

At MD Anderson Cancer Center in Houston, the Khalifa Institute for Personalized Cancer Therapy has used Guardant360 several hundred times in the past nine months to identify patients for clinical trials. The test has allowed Guardant to process results for patients who likely don’t have a large enough tumor or enough cancer DNA to be detected by the institute’s diagnostics and molecular tests.

“Essentially, no patient that is a good trial candidate is left without getting molecular testing,” said Kenna Mills Shaw, executive director of the Khalifa Institute.

Shaw said Guardant has also connected the institute with non-MD Anderson patients and their doctors for clinical trial enrollment. “By looking into their database and finding patients with rare alterations, we have good high-quality data to see if a patient is likely to respond,” she said.

In addition to being less invasive than a traditional biopsy, Guardant says its tests are cheaper as well, usually running about $5,000 per test compared with up to $20,000 for a biopsy and subsequent genomic analysis.

Still, it can be tough to get insurers to cover new technology, and there is considerable skepticism over too-good-to-be-true blood tests after the implosion of Theranos. Eltoukhy is aware of the concern and says Guardant has been transparent with its results, publishing 10 peer-reviewed, highimpact studies and even more presentations supporting its technology.

“We feel it’s critical that healthcare professionals and researchers really know the performance, as well as the limitations of the technology,” he said.

Last month, the company reached a deal with Priority Health, one of the largest health plans in Michigan, to cover the liquid biopsies. “We expect to see many more similar agreements as we’re progressing,” Eltoukhy said.

While Guardant360 continues to gain traction, the company is also involved in a new clinical trial to see if its blood test technology can be used to diagnose early stage breast, ovarian, lung, pancreatic and colorectal cancers.

An earlier proof-of-concept study showed the tests could detect cancer in 86% of early stage colorectal cancer patients, according to the company.

“We have no doubt these liquid biopsies will be one of the main, fundamental tools by which cancer is detected and treated,” Eltoukhy said.