Researchers have been dreaming for a couple decades of taking a simple blood draw from a pregnant woman, and using it to determine whether a developing fetus has Down syndrome. Now this week, after a decade of R&D fits and starts and $100 million of investment, doctors will be able to get their hands on a commercially available genomic test from Redwood City, CA-based Verinata Health that promises to deliver that answer.
The company, formerly known as Living Microsystems and Artemis Health, is poised to make that transition to the marketplace tomorrow with the rollout its Verifi prenatal genomic test. This test, developed with technology from Steve Quake’s lab at Stanford University, is the newest entrant in a market that San Diego-based Sequenom (NASDAQ: [[ticker:SQNM]]) charged into last October with a test called MaterniT21.
The companies are pursuing a multi-billion dollar market that could ultimately change the practice of medicine in the early stages of pregnancy, for as many as 4 million women who give birth in the U.S. each year. Traditional prenatal blood screens that look for biomarkers are notoriously unreliable at detecting Down syndrome or other rare chromosomal abnormalities. The gold standard tests for accuracy—amniocentesis and a procedure called CVS—are invasive, and carry a small risk of miscarriage that many women prefer to avoid. It’s only now that fast and cheap gene sequencing instruments have become available, combined with algorithms to analyze the mother’s blood, that Verinata says it can tell with startling degree of accuracy when a developing fetus has severe developmental disabilities like Down syndrome, Edwards syndrome, or Patau syndrome.
All at a cost of $1,200.
“The promise of this eventual capability has been in play for more than 20 years. Now when it’s finally here, there’s a wonder and awe in the community,” says Caren Mason, Verinata’s CEO.
The science of the new test is made possible by some of the major innovations in sequencing instruments. For years, researchers tried to search for clues about chromosomal abnormalities in maternal blood by looking for a few precious blood cells from the fetus. That proved impractical, Verinata president Richard Rava says, as a typical blood draw might have 200 billion blood cells, and only 10 of them from the fetus, and those 10 cells are typically quite fragile. “We were literally looking for the needle in the haystack,” he says.
The newest tests aspire to be “cell-free” and instead look at the DNA that’s left over in those blood samples from cells that die. Looking at the problem from that perspective, about 75-80 percent of the blood contains DNA from the mother, and 20-25 percent comes from the fetus, Rava says. “You’ve got a lot more DNA to work with,” he says.
Today’s Verinata system takes the blood sample, runs it through an Illumina HiSeq 2000 genetic analysis machine at its headquarters, and comes up with a count that can tell whether there’s a chromosomal abnormality in the fetal DNA.
Last week, Verinata published the key study that it says provides the foundation of evidence it needs to start selling its test. The company collected samples from 2,882 women with “high-risk” pregnancies, in their first and second trimesters, who were undergoing prenatal diagnostics at 60 U.S. medical centers. The data was published last week in Obstetrics & Gynecology (aka, The Green Journal), the official publication of the American College of Obstetrics and Gynecology. The study showed that Verinata’s test was accurately able to identify all 89 cases of Down syndrome (Trisomy 21); 35 out of 36 cases of Edwards syndrome (Trisomy 18); and 11 of the 14 cases of Patau syndrome (Trisomy 13). There were no false positives that could have caused unnecessary alarm.
That kind of hard data is the linchpin in
