On Wednesday night the New England Journal of Medicine published a study showing that a new, DNA-sequencing based blood test provides a dramatic improvement in accuracy at screening for Down’s syndrome and a second, related disease. That could open up a $6 billion market to the biotechnology companies that are already marketing these tests.
Each year in the U.S. there are 6.6 million pregnancies and 4 million births, according the Centers for Disease Control & Prevention. The list prices of the tests, which are sold by four different companies, range from $700 to $2500. Assuming that pricing settles in the middle of that range and that there are 5 million women who choose to have the test, that would be a $8 billion market.
But give that number a haircut. “I have to imagine pricing could come down more aggressively if guidelines expanded,” says Douglas Schenkel, an analyst at Cowen & Co. Not every pregnant woman will ever get the test. But he still argues that the market for these tests could increase six-fold from its current size of about $1 billion. Isaac Ro, an analyst at Goldman Sachs, offered similar estimates in a note to clients.
Such a market expansion could be important to all of the companies that make the tests, including Ariosa, which makes the lowest price test, Natera, and Sequenom. But the biggest winner could be Illumina, the San Diego maker of DNA sequencing gear that funded the trial and that purchased Verinata, a fourth maker of the new tests, for $350 million last year.
Illumina says it believes Verinata has strong intellectual property position in this booming new market. Beyond that, though, all four manufacturers run their tests on Illumina’s DNA sequencing machines, meaning the company wins no matter what. Francis DeSouza, Illumina’s president, said in an interview that, if anything, he expects to spend less on marketing Verinata and that the company is taking care for there to be an even playing field for the tests. It prices its test in the mid-range of the market, at a $1,500 list price.
Illumina also says that it doesn’t expect a price war, because the market expansion will be dependent on medical societies writing guidelines that endorse the new test. Right now the American College of Obstetricians and Gynecologists recommends the DNA-based tests only for mothers at high risk, including those over 35.
But the NEJM paper makes a strong argument for expanding that recommendation. Right now it’s recommended that all pregnant women be offered a pair of tests – a blood test and an ultrasound to look for fluid at the base of the fetus’ neck – to screen for three disorders caused when the baby has an extra copy of one of the 46 chromosome bundles that contain the human genetic code. There are three such disorders that occur commonly: trisomy 21, or Down syndrome, is the most common, causing diminished intellectual ability and slower growth; trisomies 18 and 13 are less common, but are often fatal for the infant.
Current screening tests yield a large number of false positives, so they must be followed up with an invasive test that samples cells from the fetus. One such test, chorionic villus sampling, has a miscarriage rate of 1 in 200; the other, amniocentesis, causes miscarriages 1 out of every 600 times.
These invasive tests would still be needed to confirm positives from the DNA tests, but they’d be used in women whose fetuses don’t have Down’s or other trisomies far less often. The NEJM study gave the old screening tests and the new DNA-based test to 1,914 pregnant women and followed them until the baby was born. For Down Syndrome, the new test gave just 6 false positives compared to 69 for the old screening tests. For trisomy 13, there were 3 false positives with DNA sequencing compared to 11 with the traditional number. For trisomy 13, the numbers were 1 and 6.
Assuming 5 million women are tested each year, that would mean 245,000 would be spared an invasive test, and 358 miscarriages might be prevented. Even at a higher cost, that could be hard for insurance companies to say no to. Some experts, including Illumina, expect that more studies will be needed to change the guidelines.
How does the new test work? Basically, by counting. Because some of the fetus’ cells circulate in the mother’s blood, researchers can sequence DNA and see if genes from any chromosomes appear too often. For a more complete description, check out the video embedded from Steve Quake at Stanford, who co-invented Verinata’s technology. His explanation starts at 5:55.
Not everyone is sure that the new technology, known as non-invasive prenatal testing, is an unmixed blessing. Hank Greely, a professor of law at Stanford Law School who has written extensively on genetic issues, says that the new test is “more reason to think NIPT will largely take over Down’s screening.” But he warns that these same methods might lead to tests for more complicated tests. “If, say, 70% of American pregnancies received broad genetic screening, the next generation would look different – some will say for better, some for worse.”