Health care is just now starting to effectively use information from the human genome to diagnose and treat disease. Nowhere is this more crucial than in the treatment of cancer, from which 7.6 million people in the U.S. die each year, and for which we spend $87 billion a year on treatment.
One of the reasons cancer is so difficult to treat is that current testing methods often don’t help doctors match specific cancers with effective drug treatments. And it’s a moving target — cancer cells are constantly changing, mutating.
Biopsy tests are crucial for showing the look and makeup of a tumor, but less good at giving doctors clues about which drugs the cancer might respond to. Biopsies are usually performed at the initial diagnosis, then often abandoned because of risk of infection and cost.
Enter Redwood City, Calif.-based Guardant Health, which has developed a blood test that can detect changes in the genetic structure of cancer cells over time. The test has become known as a “liquid biopsy” because it requires no tissue excision, just a couple of teaspoons of blood from the patient.
The test captures dead genetic material that has sloughed off living cancer cells and entered the blood stream. Sequencing the DNA from that material can provide vital clues to the current state of the cancer, and to which drug therapies to try.
After an oncologist orders a test, Guardant sends out a small kit for taking the blood from the patient. The doctor collects a couple of teaspoons of blood then Fed Exes the sample back to Foster City where Guardant does some targeted DNA sequencing on the dead cancer cells. Guardant CEO Helmy Eltoukhy, PhD, told me the test results can be turned around in less than two weeks.
Not only is the test — called Guardant360 — less expensive than a traditional biopsy, but Guardant believes it serves as a far better early warning system for mutations in the cells of a tumor. At least one study published in The New England Journal of Medicine backs up that claim. It showed that liquid biopsies can often detect the worsening of breast cancer five months before a CT scan can.
Periodic tests can tell the doctor if current drug treatments are working or failing, or if a cancer has evolved into a state where it might be sensitive to a specific cancer drug, Eltoukhy told me during a phone interview Monday.
“When you just do a biopsy, how do you know if you’re sampling the most active part of the disease? The beauty of our test is that you can see contributions from cells in the whole tumor mass,” Eltoukhy said.
Just last April Sequoia Capital and Khosla Ventures led a large $30 million funding round for Guardant Now Guardant is taking another large $50 million round to scale up operations and infrastructure. The new round is led by Lightspeed Venture Partners with participation by Formation 8 and from existing investors Khosla Ventures and Sequoia Capital.
Eltoukhy said he wasn’t sure how the cancer community would respond to his company’s test, but, it turns out, the response has been resoundingly positive. Demand for the test is high, and Guardant has the nice problem of having to build out its infrastructure to keep up.
“In our first 1000 commercial tests, we are finding cases of actionable alterations that may have been missed as a result of outdated or unobtainable biopsies,” Eltoukhy says in the funding announcement today. “With this new funding, we can scale our operations to meet the significant demand for our biopsy-free blood test and help physicians identify effective treatments for their patients.”
Eltoukhy says his company’s biggest need now is for data center hardware and software to store and manage all the data it’s collecting from the blood tests. He says a single blood test generates half of a terabyte of data, and Guardant is now performing thousands of tests a year.
But there’s a very direct payoff to the investment in data infrastructure. By analyzing the data from hundreds or thousands of tests, Guardant gets a unique look at which drugs are most, or least, effective at treating various forms of cancer. Not surprisingly, Guardant is already working with more than a dozen pharmaceutical companies that have a lot to gain from those insights.
The company is also developing a new blood test that will identify all classes of actionable tumor genomic alterations. Guardant says it will be the first and only comprehensive biopsy-free cancer test available.
Guardant says it holds more than 40 patents on its testing technology. The company points out that Guardant360 is a certified and accredited laboratory developed test; as such the test does not require FDA clearance.
So far, Guardant has taken close to $100 million in venture capital.